Publications by authors named "Zhouping Wang"

146 Publications

Effect of rutin on the physicochemical and gel characteristics of myofibrillar protein under oxidative stress.

J Food Biochem 2021 Sep 15:e13928. Epub 2021 Sep 15.

School of Food Science and Technology, Shihezi University, Shihezi, China.

The effects of rutin (6, 30, and 150 μmol/g ) on the physicochemical, structural properties and gel characteristics of myofibrillar protein (MP) under oxidative stress were investigated. The addition of rutin significantly promoted the formation of oxidized MP carbonyl derivatives and dimer tyrosine, but it cannot prevent the loss of sulfhydryl groups (-SH). With increasing rutin concentration, the hydrophobic area was gradually shielded and rutin acted as a quencher to reduce the fluorescence intensity of oxidized MP. Under the oxidative stress, rutin increased the particle size and aggravated the cleavage of protein molecules. SDS-polyacrylamide gel electrophoresis revealed that rutin further aggravated oxidized MP degradation and cross-linked form polymer which cross-linked with protein to the maximum extent at 150 μmol/g rutin content. Moderate cross-linking between protein and rutin could improve the gel strength and water holding capacity (WHC) of oxidized MP gel. For rutin concentrations of 6 and 30 μmol/g , the gels had denser network structures, as observed by scanning electron microscopy. PRACTICAL APPLICATIONS: Polyphenols of the type and dosage can change the properties of the product itself and optimize the quality of product processing. Certain polyphenols may promote the oxidation process of protein-rich products, but this does not affect the improvement of product quality. The application of natural polyphenols is the promising business direction in the development of Coregonus peled industry.
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http://dx.doi.org/10.1111/jfbc.13928DOI Listing
September 2021

Signal amplification of SiO nanoparticle loaded horseradish peroxidase for colorimetric detection of lead ions in water.

Spectrochim Acta A Mol Biomol Spectrosc 2021 Aug 30;265:120342. Epub 2021 Aug 30.

State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi 214122, China; School of Food Science and Technology, Jiangnan University, Wuxi 214122, China; International Joint Laboratory on Food Safety, Jiangnan University, Wuxi 214122, China. Electronic address:

In this work, we developed an aptamer-based optical assay for the analysis of Pb, a hazardous heavy metal that may be present in the food chain and harmful to human health. An aptamer targeted against Pb was immobilized onto the microplate as the capture probe. SiO nanoparticles (NPs) were synthesized and used as carriers of the signaling horseradish peroxidase (HRP) to achieve amplification of the optical signal. Complementary DNA (cDNA) of the aptamer was also linked to the above mentioned SiO nanoparticle (NPs) as the signal probe. The aptamers were found to be able to capture Pb, and the unbound aptamers were subsequently hybridized with cDNA-HRP-SiO conjugates. As a result, the addition of TMB-HO promoted the formation of blue products in the catalytic system. The assay adopting SiO NPs as an enhancer resulted in higher sensitivity with an LOD of 2.5 nM compared to normal procedures. The feasibility of the aptamer-based colorimetric assay was verified by successful detection of Pb in water samples with recoveries in the range of 97.4-103.52%.
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http://dx.doi.org/10.1016/j.saa.2021.120342DOI Listing
August 2021

Preparation, characterization, and antibiofilm activity of cinnamic acid conjugated hydroxypropyl chitosan derivatives.

Int J Biol Macromol 2021 Aug 26;189:657-667. Epub 2021 Aug 26.

State Key Laboratory of Food Science and Technology, Jiangnan University, Lihu Road 1800, Wuxi 214122, PR China; School of Food Science and Technology, Jiangnan University, Lihu Road 1800, Wuxi 214122, PR China; International Joint Laboratory on Food Safety, Jiangnan University, Lihu Road 1800, Wuxi 214122, PR China; Collaborative Innovation Center of Food Safety and Quality Control, Jiangnan University, Lihu Road 1800, Wuxi 214122, PR China. Electronic address:

In this study, cinnamic acid (CA) conjugated hydroxypropyl chitosan (HPCS) derivatives (HPCS-CA) with different degrees of substitution (DS) were successfully synthesized. The reaction was divided into two steps: the first step was to modify chitosan (CS) to HPCS, and the second step was to graft CA onto HPCS. Structural characterization and properties were carried out employing elemental analysis, Fourier transform infrared (FT-IR) spectroscopy, ultraviolet-visible (UV-vis) spectroscopy, nuclear magnetic resonance (NMR) spectra, X-ray diffraction (XRD), and thermogravimetric analysis (TGA). The solubility test revealed the better water solubility of derivatives than CS. In addition, in vitro antibacterial and antibiofilm tests were performed. As expected, HPCS-CA derivatives exhibited good antibacterial activity against Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli). The MIC and MBC of HPCS-CA derivatives could reach 256 μg/mL and 512 μg/mL, respectively. Confocal laser scanning microscopy (CLSM) analysis proved the inhibitory effect of HPCS-CA derivatives on S. aureus and E. coli biofilms by disrupting the formation of biofilms, reducing the thickness of biofilms, and the number of live bacteria. These results suggest the potential applicability of HPCS-CA derivatives in the treatment of biofilm-associated infections and provide a practical strategy for the design of novel CS-based antibacterial materials.
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http://dx.doi.org/10.1016/j.ijbiomac.2021.08.164DOI Listing
August 2021

A Bayesian Dynamical Approach for Human Action Recognition.

Sensors (Basel) 2021 Aug 20;21(16). Epub 2021 Aug 20.

Augmented Cognition Lab (ACLab), Department of Electrical and Computer Engineering, Northeastern University, Boston, MA 02115, USA.

We introduce a generative Bayesian switching dynamical model for action recognition in 3D skeletal data. Our model encodes highly correlated skeletal data into a few sets of low-dimensional switching temporal processes and from there decodes to the motion data and their associated action labels. We parameterize these temporal processes with regard to a switching deep autoregressive prior to accommodate both multimodal and higher-order nonlinear inter-dependencies. This results in a dynamical deep generative latent model that parses meaningful intrinsic states in skeletal dynamics and enables action recognition. These sequences of states provide visual and quantitative interpretations about motion primitives that gave rise to each action class, which have not been explored previously. In contrast to previous works, which often overlook temporal dynamics, our method explicitly model temporal transitions and is generative. Our experiments on two large-scale 3D skeletal datasets substantiate the superior performance of our model in comparison with the state-of-the-art methods. Specifically, our method achieved 6.3% higher action classification accuracy (by incorporating a dynamical generative framework), and 3.5% better predictive error (by employing a nonlinear second-order dynamical transition model) when compared with the best-performing competitors.
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http://dx.doi.org/10.3390/s21165613DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8402468PMC
August 2021

Electrochemical Determination of Capsaicinoids Content in Soy Sauce and Pot-Roast Meat Products Based on Glassy Carbon Electrode Modified with Β-Cyclodextrin/Carboxylated Multi-Wall Carbon Nanotubes.

Foods 2021 Jul 29;10(8). Epub 2021 Jul 29.

Engineering Research Center of Bio-Process of Ministry of Education, School of Food and Biological Engineering, Hefei University of Technology, 420 Feicui Road, Hefei 230601, China.

The rapid quantification of capsaicinoids content is very important for the standardization of pungent taste degree and flavor control of soy sauce and pot-roast meat products. To rapidly quantify the capsaicinoids content in soy sauce and pot-roast meat products, an electrochemical sensor based on β-cyclodextrin/carboxylated multi-wall carbon nanotubes was constructed and the adsorptive stripping voltammetry method was used to enrich samples in this study. The results showed that the excellent performance of the established electrochemical sensor was mostly because β-cyclodextrin caused the relative dispersion of carboxylated multi-wall carbon nanotubes on the glassy carbon electrode surface. Capsaicin and dihydrocapsaicin had similar electrochemical behavior, so the proposed method could determine the total content of capsaicinoids. The linearity of capsaicinoids content was from 0.5 to 100 μmol/L and the detection limit was 0.27 μmol/L. The recovery rates of different capsaicinoids content were between 83.20% and 136.26%, indicating the proposed sensor could realize trace detection of capsaicinoids content in sauce and pot-roast meat products. This work provides a research basis for pungent taste degree standardization and flavor control in the food industry.
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http://dx.doi.org/10.3390/foods10081743DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8392370PMC
July 2021

Deoxynivalenol photocatalytic detoxification products alleviate intestinal barrier damage and gut flora disorder in BLAB/c mice.

Food Chem Toxicol 2021 Oct 12;156:112510. Epub 2021 Aug 12.

State Key Laboratory of Food Science and Technology, School of Food Science and Technology, International Joint Laboratory on Food Safety, National Engineering Research Center for Functional Food, Collaborative Innovation Center of Food Safety and Quality Control of Jiangsu Province, Jiangnan University, Wuxi, 214122, China. Electronic address:

Deoxynivalenol (DON), a trichothecene mycotoxin, is one of the most globally prevalent mycotoxins mainly produced by Fusarium species. DON exposure can cause spectrum of symptoms such as nausea, vomiting, gastroenteritis, growth retardation, immunosuppression, and intestinal flora disorders in humans and animals. Therefore, the implication of DON degradation technology is of great significance for food safety. Recently, photocatalytic degradation technology has been applied for DON control. However, the toxicity of the intermediates identified in the degradation process was often ignored. In this work, based on previous successful degradation of DON and evaluation of the in vitro toxicity of DON photocatalytic detoxification products (DPDPs), we further studied the in vivo toxicity of DPDPs and mainly explored their effects on intestinal barrier function and intestinal flora in mice. The results demonstrated that the DPDPs treated with photocatalyst for 120 min effectively increased the expression of intestinal tight junction proteins and improved the disorder of gut flora. Meanwhile, compared with DON-exposed mice, the DPDPs reduced the level of inflammation and oxidative stress of intestinal tissue, and improved growth performance, enterohepatic circulation, energy metabolism, and autonomic activity. All the results indicated that the toxicity of the DPDPs irradiated for 120 min was much lower than that of DON or even nontoxic. Therefore, we hope that this photocatalytic degradation technology can be used as a promising tool for the detoxification of mycotoxins.
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http://dx.doi.org/10.1016/j.fct.2021.112510DOI Listing
October 2021

Real-time monitoring of active caspase 3 during AFB1 induced apoptosis based on SERS-fluorescent dual mode signals.

Spectrochim Acta A Mol Biomol Spectrosc 2021 Dec 17;263:120195. Epub 2021 Jul 17.

State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi 214122, PR China; School of Food Science and Technology, Jiangnan University, Wuxi 214122, PR China; International Joint Laboratory on Food Safety, Jiangnan University, Wuxi 214122, PR China; Collaborative Innovation Center of Food Safety And Quality Control in Jiangsu Province, Jiangnan University, Wuxi 214122, PR China. Electronic address:

Aflatoxin B1 (AFB1) is the most toxic mycotoxin. Usually, the toxin activated apoptosis is considered mostly through intrinsic mitochondrial pathway while the caspase family as promoter and executor plays a crucial role. In this paper, a real-time and in situ detection of caspase 3 in living cells based on SERS-fluorescence dual mode nanosensor was studied. Firstly, gold nanotriangles (AuNTs) modified with the caspase 3 specifically recognized polypeptide chain DEVD were synthesized as both SERS enhanced substrate and fluorescent quencher. Rhodamine B (Rb) as both Raman and fluorescent signal molecules was modified on the N end of DEVD chain. After active caspase 3 specifically cut off the recognition site in DEVD, partial peptide chain with Rb fell off from the surface of AuNTs. Thus, the Raman signal of Rb decreased while its fluorescent signal recovered. There was a good linear relationship between caspase 3 and both the SERS and fluorescence signals of Rb. The minimum detection limit was 0.001 nM. After cells were stimulated by AFB1, when Cyt C in the cytoplasm reached a certain level, caspase 3 was activated. This nanosensor was realized in certain living cells (HepG2, HeLa and A549). Based on monitoring the activation of specific apoptotic markers, the conduction of marker signals in real time can provide more detailed information for apoptosis.
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http://dx.doi.org/10.1016/j.saa.2021.120195DOI Listing
December 2021

A Retrospective Cohort Study of Intravenous Immunoglobulin Therapy in the Acute Phase of Kawasaki Disease: The Earlier, the Better?

Cardiovasc Ther 2021 18;2021:6660407. Epub 2021 Jun 18.

Department of Cardiology, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou 510120, China.

Background: Although intravenous immunoglobulin (IVIG) is expected to prevent coronary artery abnormalities of Kawasaki disease (KD) in the acute phase, the timing and effectiveness of IVIG remain to be determined. The association of timing of IVIG administration in KD patients with coronary artery abnormalities is evaluated in this cohort study.

Methods: We systematically studied KD patients from two participating institutions between 2015 and 2017. To reveal the effectiveness of IVIG treatment, these patients were classified into four groups regarding the time of IVIG treatment. Primary outcome was coronary artery abnormalities by echo at diagnosis and 12 months follow-up; secondary outcomes included inflammatory markers.

Results: A total of 1281 patients were included in this study. The best time of IVIG treatment cut-off values in 12 months follow-up for predicting coronary artery abnormalities was days 7.5 of illness onset. According to the best time of IVIG treatment cut-off values, all patients were classified into 4 groups. Group 1 was defined as earlier IVIG treatment administration on days ≤4 of the illness ( = 77). Group 2 was defined with days 5-7 ( = 817), group 3 with days 8-10 ( = 249), group 4 with days >10 ( = 138). A greater proportion of IVIG-resistant KD patients were group 4 than the other three groups, and there were significant differences ( < 0.05). The incidence of coronary artery lesions (CALs) and coronary artery aneurysms (CAAs) in group 3 and group 4 was higher than that in group 1 ( < 0.05) and group 2 ( < 0.05) during a 12-month follow-up. Additionally, the incidence of CALs in group 1 was higher than that in group 2 but without statistical significance ( > 0.05). The OR was significantly higher for those who started IVIG administration more than 7 days from the onset was positively associated with the occurrence of CALs (OR, 5.3; 95% CI, 2.0-13.9) and CAAs (OR, 13.5; 95% CI, 2.9-14.1) 12 months after initial onset. Multivariate regression revealed that the timing of IVIG treatment and IVIG-resistance was independent risk factors of CALs.

Conclusions: IVIG treatment less than 7 days after illness onset are found to be sufficient for preventing developing coronary artery abnormalities in KD patients. Earlier IVIG treatment administration within 4 days may not increase the higher incidence of coronary artery abnormalities and IVIG resistance (Chinese Clinical Trial Registry:ChiCTR1800015800).
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http://dx.doi.org/10.1155/2021/6660407DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8233071PMC
July 2021

Preparation and characterization of k-carrageenan/konjac glucomannan/TiO nanocomposite film with efficient anti-fungal activity and its application in strawberry preservation.

Food Chem 2021 Dec 24;364:130441. Epub 2021 Jun 24.

State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi 214122, China; School of Food Science and Technology, Jiangnan University, Wuxi 214122, China; International Joint Laboratory on Food Safety, Jiangnan University, Wuxi 214122, China. Electronic address:

A nano-composite film was prepared from k-carrageenan (KC), konjac glucomannan (KGM) and TiO nanoparticles (NPs) by solvent casting method. The morphology and structure of the KC/KGM based nano-composite films prepared from different weight ratio of TiO NPs were characterized by SEM, XRD and FT-IR techniques. The addition of TiO NPs to KC/KGM films improved the mechanical, thermal, structural, and barrier properties of nano-composite films. In particular, the film containing 7 wt% of TiO NPs exhibited effective photocatalytic anti-fungal activity (79%) for Penicillium viridicatum after irradiating 6 h through generating reactive oxygen species thus destroying the fungi. Benefitting from the improved characteristics investigated above, the nano-composite films showed a favorable effect on strawberry storage. Overall, the fabricated KC/KGM/TiO nano-composite films have a broad application in the field of food preservation and packaging applications.
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http://dx.doi.org/10.1016/j.foodchem.2021.130441DOI Listing
December 2021

The isolation of high-affinity ssDNA aptamer for the detection of ribavirin in chicken.

Anal Methods 2021 07 22;13(27):3110-3117. Epub 2021 Jun 22.

State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi 214122, China.

The abuse of ribavirin, an antiviral drug, in poultry breeding can cause quality degradation and drug resistance. So it is of great importance to establish a simple and effective method for detecting ribavirin in foods. In this work, aptamers that could especially bind to ribavirin with high affinity were obtained by the Capture-SELEX method. After 15 rounds of enrichment, ssDNA library pool was enriched and then analyzed by high-throughput sequencing. The seven most enriched sequences were selected as candidate aptamers for affinity and specificity characterization. Among the candidate aptamers, APT-1 was proved to be the optimal aptamer. The dissociation constant (K) values of APT-1 obtained by the two methods of colorimetric and fluorescence were 34.34 ± 6.038 nmol L, 61.19 ± 21.48 nmol L, respectively. To study the binding mechanism of the selected aptamer, molecular docking was conducted and results indicated that hydrogen bonds were formed at binding sites located at G37, T38, A40, T53 and A54. Furthermore, to confirm the practicability of the selected aptamer, a fluorescence assay was designed, showing the liner range within 1.0-50 ng mL and the low detection limit of 0.67 ng mL. Besides, the aptamer was applied for the detection of ribavirin in chicken samples and the recoveries ranged from 87.26% to 105.57%, which showed great application potential in food safety.
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http://dx.doi.org/10.1039/d1ay00606aDOI Listing
July 2021

Screening and application of a broad-spectrum aptamer for acyclic guanosine analogues.

Anal Bioanal Chem 2021 Aug 10;413(19):4855-4863. Epub 2021 Jun 10.

State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, 214122, China.

Acyclic guanosine analogues, a class of widely used antiviral drugs, can cause chronic toxicity and virus resistance. Therefore, it is essential to establish rapid and accurate methods to detect acyclic guanosine analogues. In this study, five acyclic guanosine analogues (acyclovir, famciclovir, ganciclovir, penciclovir, and valaciclovir) were used as positive targets to obtain broad-spectrum aptamers through Capture-SELEX technology. Real-time quantitative PCR (Q-PCR) was used to monitor the aptamer SELEX process. After the sixteen rounds of selection against mixed targets, sequences were obtained by high-throughput sequencing (HTS). Furthermore, a broad-spectrum aptamer, named CIV6, was found as the higher performance aptamer that was suitable for five acyclic guanosine analogues by graphene oxide (GO) polarization and fluorescence assay. Finally, the aptamer CIV6 was used to construct GO fluorescence assay to detect five acyclic guanosine analogues. The limits of detection (LOD) of acyclovir, famciclovir, ganciclovir, penciclovir, and valaciclovir were 0.48 ng·mL, 0.53 ng·mL, 0.50 ng·mL, 0.56 ng·mL, and 0.38 ng·mL, respectively.
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http://dx.doi.org/10.1007/s00216-021-03446-wDOI Listing
August 2021

A phosphorescence resonance energy transfer-based "off-on" long afterglow aptasensor for cadmium detection in food samples.

Talanta 2021 Sep 22;232:122409. Epub 2021 Apr 22.

Academy of Food Interdisciplinary Science, School of Food Science and Technology, Dalian Polytechnic University, Qinggongyuan 1, Ganjingzi District, Dalian, 116034, China; National Engineering Research Center of Seafood, Dalian Polytechnic University, 116034, China; Collaborative Innovation Center of Seafood Deep Processing, Dalian Polytechnic University, Dalian, 116034, China. Electronic address:

Cadmium contamination is a severe food safety risk for human health. Herein, a long afterglow "off-on" phosphorescent aptasensor was developed based on phosphorescence resonance energy transfer (PRET) for the detection of Cd in complex samples which minimizes the interference of background fluorescence. In this scheme, initially the phosphorescence of Cd-binding aptamer conjugated long afterglow nanoparticles (ZnGeO:Mn) was quenched by black hole quencher 1 (BHQ) modified complementary DNA. Upon encountering of Cd, the aptamer interacted with Cd and the complementary DNA with BHQ was released, leading to phosphorescence recovery. The content of Cd could be quantified by the intensity of phosphorescence recovery with 100 μs gate time (which eliminated the sample autofluorescence) with a linear relationship between 0.5 and 50 μg L and a limit of detection (LOD) of 0.35 μg L. This method was successfully demonstrated for Cd detection in drinking water and yesso scallop samples. The "off-on" phosphorescent aptasensor based on PRET of long afterglow nanomaterials could be an effective tool for Cd detection in food samples.
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http://dx.doi.org/10.1016/j.talanta.2021.122409DOI Listing
September 2021

Fabrication of gold/silver nanodimer SERS probes for the simultaneous detection of Salmonella typhimurium and Staphylococcus aureus.

Mikrochim Acta 2021 05 27;188(6):202. Epub 2021 May 27.

State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, 214122, People's Republic of China.

Salmonella typhimurium (S. typhimurium) and Staphylococcus aureus (S. aureus) are the two most important foodborne pathogens which can easily cause disease infections. Here, the aptamer-facilitated gold/silver nanodimer SERS probes were built for the simultaneous detection of the two bacteria with the help of magnetic separation enrichment. First, two nanodimer SERS signal probes and two magnetic capture probes each connected with the specific aptamer were fabricated. The distance between gold and silver nanoparticles in the dimer can amplify the Raman signal (Cy3 and Rox) at the junction but modified in the aptamer sequence. Then, after the addition of S. typhimurium and S. aureus, the sandwich-like composite structures "SERS signal probes-target-magnetic capture probes" formed because of the high affinity between aptamer sequences and their target bacteria. Under the optimal experimental conditions, the linear correlations between Raman intensity and the logarithm of the concentration of bacteria were y = 876.95x-67.84 (R = 0.9865) for S. typhimurium and y = 1280.43x-1752.6 (R = 0.9883) for S. aureus. The SERS detection showed the nanodimer probe had high selectivity. Besides, the recovery experiment in milk sample indicated good accuracy compared with the traditional plate counting method.
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http://dx.doi.org/10.1007/s00604-021-04791-4DOI Listing
May 2021

Chlorin e6 conjugated chitosan as an efficient photoantimicrobial agent.

Int J Biol Macromol 2021 Jul 14;183:1309-1316. Epub 2021 May 14.

State Key Laboratory of Food Science and Technology, Jiangnan University, Lihu Road 1800, Wuxi 214122, PR China; School of Food Science and Technology, Jiangnan University, Lihu Road 1800, Wuxi 214122, PR China; International Joint Laboratory on Food Safety, Jiangnan University, Lihu Road 1800, Wuxi 214122, PR China; Collaborative Innovation Center of Food Safety and Quality Control, Jiangnan University, Lihu Road 1800, Wuxi 214122, PR China. Electronic address:

The development of antibacterial agents with high bacteria-binding capability and antibacterial efficiency is highly desirable. Herein, cationic polysaccharide chitosan (CS) was combined with photosensitizer Chlorin e6 (Ce6) to construct a novel photodynamic antibacterial agent (CS-Ce6 conjugates) for combating gram-positive bacteria Staphylococcus aureus (S. aureus) and gram-negative bacteria Escherichia coli (E. coli). CS-Ce6 conjugates with different degrees of substitution (DS) were synthesized and characterized by a spectroscopic method and organic elemental analysis to understand the relationship between structure and antibacterial effect. CS-Ce6 conjugates revealed good reactive oxygen species (ROS) generation ability and photodynamic antibacterial effect. Meanwhile, they both were positively correlated with DS in the range of 4.81% ~ 11.56% resulting in stronger photodynamic antibacterial ability. These findings highlight that CS-Ce6 conjugates have the potential as an effective photodynamic bactericidal agent in the antibacterial field.
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http://dx.doi.org/10.1016/j.ijbiomac.2021.05.085DOI Listing
July 2021

Label free structure-switching fluorescence polarization detection of chloramphenicol with truncated aptamer.

Talanta 2021 Aug 23;230:122349. Epub 2021 Mar 23.

State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, 214122, China; School of Food Science and Technology, Jiangnan University, Wuxi, 214122, China; National Engineering Research Center for Functional Food, Jiangnan University, Wuxi, Jiangsu, 214122, China; International Joint Laboratory on Food Safety, Jiangnan University, Wuxi, 214122, China; Collaborative Innovation Center of Food Safety and Quality Control of Jiangsu Province, Jiangnan University, Wuxi, 214122, China. Electronic address:

In this study, the original chloramphenicol aptamer containing 80 bases was truncated to 30 bases with high affinity by the SYBR Green I assay. It was found that the ionic strength and type affect the recognition of aptamers, especially magnesium ion played a vital role in the binding process. Furthermore, the binding performance of aptamer, including binding mode, key binding sites and conformational changes were further investigated by circular dichroism spectroscopy, UV-vis absorption spectrum and molecular docking. Based on these research data, we inferred that chloramphenicol bound to the minor groove region in the aptamer double helix. Finally, the optimized aptamer LLR10 was used to develop a novel label free fluorescence polarization assay to detect chloramphenicol within SYBR Green I as the source of fluorescence polarization signal. Under optimal conditions, the designed method showed a linear detection range of 0.1-10 nM with a detection limit of 0.06 nM. Additionally, the aptasensor exhibited a high accuracy to the detection of chloramphenicol in milk samples with a recovery rate from 93.7% to 98.4%. Therefore, the developed label free fluorescence polarization aptasensor provides a new idea for the rapid, reliable and sensitive detection of chloramphenicol, which can be applied to food safety control.
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http://dx.doi.org/10.1016/j.talanta.2021.122349DOI Listing
August 2021

A general strategy to synthesis chitosan oligosaccharide-O-Terpenol derivatives with antibacterial properties.

Carbohydr Res 2021 May 14;503:108315. Epub 2021 Apr 14.

State Key Laboratory of Food Science and Technology, Jiangnan University, Lihu Road 1800, Wuxi, 214122, PR China; School of Food Science and Technology, Jiangnan University, Lihu Road 1800, Wuxi, 214122, PR China; International Joint Laboratory on Food Safety, Jiangnan University, Lihu Road 1800, Wuxi, 214122, PR China; Collaborative Innovation Center of Food Safety and Quality Control, Jiangnan University, Lihu Road 1800, Wuxi, 214122, PR China.

The objectives of the present study are to synthesize a series of chitosan oligosaccharide-O-Terpenol (COS-O-Ter) derivatives and their implication to evaluate in vitro antibacterial activity. Herein, a general strategy is described for preparing COS-O-Ter derivatives, including substitution and deprotection reactions. The structures of COS-O-Ter derivatives were characterized by FT-IR, H NMR, XRD, TGA, and elemental analysis. COS-O-Ter derivatives revealed the excellent solubility and in vitro antibacterial activity. Moreover, their antibacterial activities were more sensitive to Staphylococcus aureus (S. aureus) than Escherichia coli (E. coli) indicating the effective potential application of COS-O-Ter derivatives as natural antibacterial agents. The aforementioned study opens a pave to expand the application scope of COS and its derivatives in the food and pharmaceutical industries.
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http://dx.doi.org/10.1016/j.carres.2021.108315DOI Listing
May 2021

Capture-SELEX for aptamer selection: A short review.

Talanta 2021 Jul 5;229:122274. Epub 2021 Mar 5.

State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, China; School of Food Science and Technology, Jiangnan University, Wuxi, China; International Joint Laboratory on Food Safety, Jiangnan University, Wuxi, China; Synergetic Innovation Center of Food Safety and Quality Control of Jiangsu Province, China. Electronic address:

The emerging aptamer, developed through the systematic evolution of ligands by exponential enrichment (SELEX) process, has revolutionized and facilitated the discoveries in basic research. Among all SELEX technology, Capture-SELEX is a variant of the in vitro selection process, which is suitable for isolating aptamers against small molecules. Capture-SELEX library was developed to enable the immobilization of the oligonucleotides instead of the target molecules during the aptamer selection process. The review provides an update on the recent-advances in this new screening method with particular emphasis on key points of capture protocol and its applications. The limitations and the prospects of the Capture-SELEX are also discussed. We hope that present review will inspire more researchers to understand the selection problems from the perspective of Capture-SELEX. Moreover, it will open new pave to improve the efficiency and success of screening to meet the growing demand for aptasensor discovery in small molecules.
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http://dx.doi.org/10.1016/j.talanta.2021.122274DOI Listing
July 2021

Homozygous of Gene rs1751034 C Allele Is Related to Increased Risk of Intravenous Immunoglobulin Resistance in Kawasaki Disease.

Front Genet 2021 15;12:510350. Epub 2021 Mar 15.

Department of Blood Transfusion and Clinical Biological Resource Bank, Institute of Pediatrics, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, China.

Kawasaki disease (KD) is a systemic vasculitis in childhood, which mainly causes damage to coronary arteries, and intravenous immunoglobulin (IVIG) is the initial therapy. IVIG resistance increased risk of coronary complication in KD. And genetic background is involved in the occurrence of IVIG resistance. Our previous study indicated the susceptibility of SNPs to KD. This study was to clarify the relationship between polymorphisms and IVIG resistance. We genotyped the six polymorphisms of gene in 760 cases of KD using Taqman methods. Among the six polymorphisms, only the rs1751034 polymorphism was significantly associated with IVIG resistance in KD [CC vs. TT: adjusted odds ratio (OR) = 2.54, 95% confidence interval (CI) = 1.21-5.34; CC vs. TT/TC: adjusted OR = 2.33, 95% CI = 1.12-4.83, = 0.023]. Combined analysis of three polymorphisms indicated that patients with 3-6 risk genotypes exhibited significantly elevated risk of IVIG resistance, when compared with those with 0-2 risk genotypes (adjusted OR = 1.52, 95% CI = 1.04-2.22, = 0.0295). Stratified analysis revealed that in term of age and gender, rs1751034 CC carriers were associated with increased risk of IVIG resistance in those aged ≤ 60 months (adjusted OR = 2.65, 95% CI = 1.23-5.71, = 0.0133). The presence of three or more risk genotypes was significantly associated with risk of IVIG resistance in children younger than 5 years of age and males. Our results suggest that rs1751034 CC is associated with increased risk of IVIG resistance in KD.
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http://dx.doi.org/10.3389/fgene.2021.510350DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8005616PMC
March 2021

Deoxynivalenol-induced cell apoptosis monitoring using a cytochrome c-specific fluorescent probe based on a photoinduced electron transfer reaction.

J Hazard Mater 2021 08 13;415:125638. Epub 2021 Mar 13.

State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi 214122, China; School of Food Science and Technology, Jiangnan University, Wuxi 214122, China; International Joint Laboratory on Food Safety, Jiangnan University, Wuxi 214122, China. Electronic address:

Deoxynivalenol (DON) is considered a mycotoxin that is toxic to the agricultural environment and human body. It is necessary to study the pathophysiological mechanism of DON toxicity at the cellular level. Cytochrome c (Cyt c), as an important biomarker of DON-induced apoptosis that may lead to a bipartite 'point-of-no return' event, is of great significance to be detected using cell imaging. Herein, we synthesized a DON-deactivated emission fluorescent probe, the molecularly imprinted polymer-coated quantum dots ([email protected]), for monitoring the Cyt c level with a photoinduced electron transfer strategy. The [email protected] probe can be easily loaded into cells and perform well due to its great sensitivity and selectivity and its fluorescence was gradually quenched with the increasing concentration (0-10 μM) and incubation time (0-7.5 h) of DON. Cell imaging results of apoptosis induced by DON was consistent with that of the cell counting kit-8 assay and flow cytometry technique. The developed method can be used to monitor DON-induced apoptosis and provide an early-warning system for the contaminant toxicity.
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http://dx.doi.org/10.1016/j.jhazmat.2021.125638DOI Listing
August 2021

Impact of Platelet Glycoprotein Ia/IIa C807T Gene Polymorphisms on Coronary Artery Aneurysms of KD Patients.

Cardiol Res Pract 2021 23;2021:4895793. Epub 2021 Feb 23.

Department of Clinical Biological Resource Bank, Guangzhou Institute of Pediatrics, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou 510623, China.

Background: Kawasaki disease (KD) is a systemic vasculitis of unknown etiology in children. Coronary artery abnormalities are the most common complications of KD. Recent evidence showed that genetic polymorphisms may lead to susceptibility to KD. Genetic variants in platelet glycoprotein have been reported to be associated with coronary artery disease. The aim of the present study is to investigate the correlation between the role of platelet glycoprotein and coronary artery aneurysms in KD patients.

Methods: We did a case-control study that enrolled 818 KD patients and 1401 healthy children with the same age and sex from January 2013 to December 2016. Analysis of single-nucleotide polymorphism (rs1126643) of the platelet glycoprotein Ia/IIa C807T was performed by multiplex polymerase chain reactions in this study.

Results: A significant difference in the genotype distribution between KD cases and controls was observed for the glycoprotein Ia/IIa C807T (rs1126643) polymorphism (=0.026). Compared with the healthy children, the rs1126643T allele carriers had odds ratio (OR) of 0.63 for developing KD (TT vs. CC: adjusted OR = 0.62, 95% confidence interval (CI) = 0.43-0.88,=0.0078; TT vs. CT/CC: adjusted OR = 0.63, 95% CI = 0.44-0.889,=0.0093). Furthermore, we also found that children less than 60 months of age and female patients with rs1126643 T allele carriers had an adjusted OR of 0.66 (95% CI = 0.46-0.95) for noncoronary artery aneurysm patients (=0.0242). Single-nucleotide polymorphism rs1126643 TT seems to represent a protective factor against KD in coronary artery aneurysm formation in multivariate analysis.

Conclusions: The platelet glycoprotein Ia/IIa T allele carriers may have a protective effect on the risk of coronary artery aneurysms of KD patients, especially in females and children aged less than 60 months. These results may provide evidence for platelet glycoprotein Ia/IIa gene polymorphisms in the pathogenesis of KD patients.
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http://dx.doi.org/10.1155/2021/4895793DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7929693PMC
February 2021

Nuclease-assisted target recycling signal amplification strategy for graphene quantum dot-based fluorescent detection of marine biotoxins.

Mikrochim Acta 2021 03 9;188(4):118. Epub 2021 Mar 9.

State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, 214122, People's Republic of China.

Saxitoxin (STX) is a major marine toxin from shellfish, and it is responsible for paralytic shellfish poisoning (PSP). In this study, a highly sensitive and rapid aptamer assay was developed for STX detection by combining fluorescence resonance energy transfer (FRET) and nuclease-assisted target recycling signal amplification. The aptamer STX-41 conjugated with graphene quantum dots (GQDs) was adsorbed on magnetic reduced graphene oxide (MRGO) to establish a fluorescence quenching system. Then, the binding between STX and aptamer induced the desorption of GQD-aptamer from MRGO and the restoring of fluorescence for the fluorescent determination of STX. The digestion of the target bound aptamer by DNase I could release the target for recycling thus achieving signal amplification. Under the optimized conditions, the aptamer assay showed a wide detection range (0.1-100 ng·mL), low detection limit (LOD of 0.035 ng·mL), high specificity, good recovery (86.75-94.08% in STX-spiked clam samples) and repeatability (RSD of 4.27-7.34%). Combined with fluorescent detection technology, signal amplification technology, and magnetic separation technology, the proposed method can be used to detect STX in seafood products successfully.
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http://dx.doi.org/10.1007/s00604-020-04684-yDOI Listing
March 2021

Integrin α2 gene polymorphism is a risk factor of coronary artery lesions in Chinese children with Kawasaki disease.

Pediatr Rheumatol Online J 2021 Feb 8;19(1):12. Epub 2021 Feb 8.

Department of Blood Transfusion , Clinical Biological Resource Bank and Clinical Lab, Guangzhou Institute of Pediatrics, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, 510623, Guangdong, China.

Background: Kawasaki disease (KD) is a systemic vasculitis, and the formation of coronary artery lesions(CAL) is its most common sequela. Both genetic and environmental factors are considered to be important factors of in KD. Integrin α2 (ITGA2) is a transmembrane receptor that is associated with susceptibility to several diseases, but its relevance to KD with CAL is unclear.

Methods: We genotyped ITGA2 rs1126643 in 785 KD patients with the CAL and no-CAL(NCAL) (300 patients with CAL, and 485 age- and sex-matched patients with NCAL). OR (95% CI) and adjusted OR (95% CI) were used to evaluate the intensity of the association.

Results: We found a significantly increased risk of KD with CAL associated with ITGA2 rs1126643 genotypes (CT vs CC: adjusted OR = 1.57, 95% CI = 1.16-2.12, P = 0.0032; CT/TT vs CC: adjusted OR = 1.49, 95% CI = 1.12-2.00, P = 0.0068; T vs C: adjusted OR = 1.66, 95% CI = 1.16-2.51, P = 0.0165). Moreover, we found that carriers of the CT/TT genotype had a significant risk of KD with coronary artery lesion susceptibility for children ≤60 months of age, and the CT/TT genotype was significantly associated with an increased risk of SCAL formation and MCAL formation when compared with the CC genotype.

Conclusion: ITGA2 rs1126643 was associated with increased susceptibility and severity of CAL in KD.
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http://dx.doi.org/10.1186/s12969-021-00494-5DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7869497PMC
February 2021

Methylprednisolone Pulse Therapy or Additional IVIG for Patients with IVIG-Resistant Kawasaki Disease.

J Immunol Res 2020 24;2020:4175821. Epub 2020 Nov 24.

Department of Cardiology, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, Guangdong, China.

There have been no robust data from clinical trials to guide the clinician in the choice of therapeutic agents for the child with intravenous immunoglobulin (IVIG) resistance. The treatment regimen for IVIG-resistant patients varies between institutions, and the best option has not yet been established. Therefore, in this trial, a total of 955 patients with Kawasaki disease (KD) were selected and were initially treated with IVIG (2 g/kg), of whom 80 (8.38%) assessed as IVIG resistant were randomly divided into two groups: Group A received the second IVIG treatment ( = 40), and Group B received methylprednisolone pulse therapy (MPT, = 40). The whole fever time, duration of fever after retreatment, hospital days, medical costs, readmission rate, and laboratory examination difference (△) were calculated. Coronary artery lesion (CAL) outcomes were followed up over two years. Patients in the MPT group had shorter fever after retreatment and lower medical costs; more rapid declines in C-reactive protein (CRP), neutrophils (N%), and platelet (PLT) levels; and more rapid rise in sodium. However, they also probably had a higher incidence of treatment failure and CALs than the additional IVIG treatment group in the long-term follow-up. Caution is still required in the use of MPT to treat IVIG-resistant KD.
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http://dx.doi.org/10.1155/2020/4175821DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7707959PMC
August 2021

A Highly Sensitive "on-off" Time-Resolved Phosphorescence Sensor Based on Aptamer Functionalized Magnetite Nanoparticles for Cadmium Detection in Food Samples.

Foods 2020 Nov 27;9(12). Epub 2020 Nov 27.

School of Food Science and Technology, Dalian Polytechnic University, Qinggongyuan 1, Ganjingzi District, Dalian 116034, China.

Cadmium contamination is a severe threat to food safety. Therefore, the development of sensitive and selective cadmium detection strategies is urgently required. The elimination of background autofluorescence generated from the food matrix is critical to the optical assay for cadmium detection. Herein, a time-resolved phosphorescence sensor based on an "on-off" strategy was developed for cadmium determination in food samples. The phosphorescence nanoparticles were used as a luminous material to minimize the interference of background autofluorescence. The cadmium-binding aptamer was immobilized onto the magnetic beads and combined with a black hole quencher 1 (BHQ) with complementary DNA as the target recognition element. With the presence of cadmium, the cadmium-binding aptamer bound to cadmium specifically and resulted in the release of BHQ. The free BHQ remained in the solution after magnetic separation and quenched the phosphorescence. The phosphorescence intensity was negatively related to the concentration of cadmium. Under optimal conditions, the time-resolved phosphorescence sensor showed a linear response to cadmium concentration within a range from 0.05 to 5 ng mL and with a detection limit of 0.04 ng mL. This "on-off" time-resolved phosphorescence sensor was successfully applied for cadmium detection in spring water and clam samples, which provided a rapid and straightforward method.
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http://dx.doi.org/10.3390/foods9121758DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7760395PMC
November 2020

Facile synthesis and antibacterial activity of geraniol conjugated chitosan oligosaccharide derivatives.

Carbohydr Polym 2021 Jan 16;251:117099. Epub 2020 Sep 16.

State Key Laboratory of Food Science and Technology, Jiangnan University, Lihu Road 1800, Wuxi 214122, PR China; School of Food Science and Technology, Jiangnan University, Lihu Road 1800, Wuxi 214122, PR China; International Joint Laboratory on Food Safety, Jiangnan University, Lihu Road 1800, Wuxi 214122, PR China; Collaborative Innovation Center of Food Safety and Quality Control, Jiangnan University, Lihu Road 1800, Wuxi 214122, PR China.

A new chitosan oligosaccharide derivative (COS-N-Ger), based on geraniol (Ger) modificated onto the NH position of chitosan oligosaccharide (COS) via a facile method, was prepared and employed to evaluate in vitro antibacterial activity. The structures of COS-N-Ger derivatives were confirmed by FT-IR, H, C NMR, and elemental analysis. The characterization results showed successful synthesis of derivatives and the degrees of substitution (DS) of COS-N-Ger1-3 were from 0.260 to 0.283 with the yields up to 78 %. The in vitro antibacterial activity evaluation results presented a significant inhibition effect of COS-N-Ger1-3 derivatives on Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) as compared to COS. Moreover, their antibacterial activities were dose-dependent and more sensitive to S. aureus than E. coli. The results provide reliable theoretical supports for exploring the application of COS derivatives in the food industry as new potential antibacterial agents.
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http://dx.doi.org/10.1016/j.carbpol.2020.117099DOI Listing
January 2021

Application of [email protected] quantum dots for ROS imaging and evaluation of deoxynivalenol-mediated oxidative stress in living cells.

Food Chem Toxicol 2020 Dec 29;146:111834. Epub 2020 Oct 29.

State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, 214122, China; School of Food Science and Technology, Jiangnan University, Wuxi, 214122, China; International Joint Laboratory on Food Safety, Jiangnan University, Wuxi, 214122, China; Collaborative Innovation Center of Food Safety and Quality Control of Jiangsu Province, Jiangnan University, Wuxi, 214122, China; National Engineering Research Center of Seafood, School of Food Science and Technology, Dalian Polytechnic University, Dalian, 116034, China. Electronic address:

Deoxynivalenol (DON), a trichothecene mycotoxin, has attracted global attention due to its prevalence and substantial effects on animal and human health. DON induces the upregulation of intracellular reactive oxygen species (ROS) by disrupting the normal mitochondrial functionality, which causes oxidative stress, cell apoptosis, and even severe disorders. The aim of present work is to develop a simple, convenient, and in situ method for monitoring ROS and evaluating DON-mediated oxidative stress. Herein, polyethylene glycol-modified [email protected] quantum dots (QDs) were employed as simple and convenient nanoprobe for ROS imaging and oxidative stress evaluating induced by DON in living cells. The results demonstrated 5 ppm QDs nanoprobe can be easily loaded into cells via endocytosis without readily observable oxidative effects. Once in presence of DON, the augmented ROS directly oxidize the QDs nanoprobe, which leads to the destruction of the QDs structure and quenched fluorescence. According to the weakened fluorescence intensity (FI), the oxidative damage mediated by DON can be rapidly monitored and found that the oxidative stress was the most severe when the DON concentration exceeded 10 ppm. The developed QDs nanoprobe is also suitable for assessing other mycotoxins and chemicals. We hope it will be beneficial for the early screening of toxic and harmful substances in in vitro toxicology.
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http://dx.doi.org/10.1016/j.fct.2020.111834DOI Listing
December 2020

Analysis of the anti-inflammatory effect of the aptamer LA27 and its binding mechanism.

Int J Biol Macromol 2020 Dec 12;165(Pt A):308-313. Epub 2020 Sep 12.

State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi 214122, China; School of Food Science and Technology, Jiangnan University, Wuxi 214122, China. Electronic address:

Lipopolysaccharide (LPS) is an important pathogenic factor and plays a key role in human diseases such as fever, shock, and sepsis. Blocking the toxicity of LPS through antagonism is considered the best choice for the treatment of LPS-induced diseases. In this research, nucleic acid aptamer LA27, which was previously selected and optimized by our group, was used as an LPS inhibitor to treat human HepG2 cells stimulated by LPS from four different sources (StLPS, EcoliLPS, PaLPS, and SeLPS): the levels of expression of three inflammatory cytokines factors (TNF-α, IL-1β, and IL-6) were evaluated by ELISA on LA27-treated and untreated cells incubated for 12 h with LPS. The results of the assays indicated that LA27 exhibited considerable anti-inflammatory activity. The binding site and interactions between aptamer LA27 and LPSs were also simulated using Molecular Operating Environment (MOE) 2018 software. MOE simulation results showed that, under a combination of the hydrophobic interaction, hydrogen bonding, and electrostatic interactions, the fatty acid chain of LPS could interact with the wide hydrophobic region of the aptamer, constituting its major groove, and formed stable complex of T-type. The present research indicated that LA27 might be a potential therapeutic agent for sepsis and other diseases, which provides a new path for the development of LPS antagonists.
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http://dx.doi.org/10.1016/j.ijbiomac.2020.09.052DOI Listing
December 2020

Structure-switching fluorescence aptasensor for sensitive detection of chloramphenicol.

Mikrochim Acta 2020 08 19;187(9):505. Epub 2020 Aug 19.

State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, 214122, China.

The performance of chloramphenicol aptamer, including binding thermodynamics, structure switching, and binding domain, was investigated by isothermal titration calorimetry, circular dichroism, and molecular docking. Then, a new fluorescence aptasensor was developed with signal amplification mediated by exonuclease I-catalyzed reaction and hybridization chain reaction (HCR) for chloramphenicol detection. In this system, the aptamer-binding domain is blocked by the initiator of HCR, the aptamer undergoes structure switching in the presence of chloramphenicol, and DNA dissociation occurs. The released aptamer is subsequently recognized and cleaved by Exo I to set free chloramphenicol. With the Exo I-assisted chloramphenicol recycling, an increasing number of initiators were exposed from the digestion of the initiator-aptamer complex. Then, the chain-like assembly of FAM labeled H1 and H2 through HCR was triggered by the initiator, generating a long DNA polymer. Under optimum conditions, the aptasensor exhibited a log-linear range from 0.001 to 100 nM of chloramphenicol and a detection limit of 0.3 pM. Additionally, the designed biosensing platform was applied to determine chloramphenicol in milk and lake water with high accuracy. The current approach provides a new avenue to develop sensitive aptasensors with the assistance of binding mechanism between aptamer and target compounds. Graphical abstract.
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http://dx.doi.org/10.1007/s00604-020-04471-9DOI Listing
August 2020

A colorimetric aptamer-based method for detection of cadmium using the enhanced peroxidase-like activity of Au-MoS nanocomposites.

Anal Biochem 2020 11 4;608:113844. Epub 2020 Aug 4.

State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, 214122, PR China; School of Food Science and Technology, Jiangnan University, Wuxi, 214122, PR China; International Joint Laboratory on Food Safety, Jiangnan University, Wuxi, 214122, PR China; Collaborative Innovation Center of Food Safety and Quality Control of Jiangsu Province, Jiangnan University, Wuxi, 214122, China. Electronic address:

In this work, a colorimetric aptamer-based method for detection of cadmium using gold nanoparticles modified MoS nanocomposites as enzyme mimic is established. In short, biotinylated Cd aptamers are immobilized by biotin-avidin binding on the bottoms of the microplate, the complementary strands of Cd aptamers are connected to the Au-MoS nanocomposites which have the function of enhanced peroxidase-like activity. The csDNA-Au-MoS signal probe and target Cd compete for binding Cd aptamer, the color change can be observed by addition of chromogenic substrate, thereby realizing visual detection of Cd. The absorbance of the solution at 450 nm has a clear linear relationship with the Cd concentration. The linear range is 1-500 ng/mL, and the limit of detection is 0.7 ng/mL. The assay was used to test white wine samples, the results are consistent with those of atomic absorption spectrometry; which prove that this method can be used for detection of Cd in real samples.
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http://dx.doi.org/10.1016/j.ab.2020.113844DOI Listing
November 2020

Changes in the phospholipid molecular species in water-boiled salted duck during processing based on shotgun lipidomics.

Food Res Int 2020 06 5;132:109064. Epub 2020 Feb 5.

State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi 214122, China; School of Food Science and Technology, Jiangnan University, Wuxi 214122, China. Electronic address:

Knowledge of the changes in the phospholipid molecular species during processing is helpful to understanding the complicated mechanisms of lipid degradation and transformation. The shotgun lipidomics strategy was utilized to analyze the phospholipid (PL) molecular species in raw Pekin duck and the subsequent dynamic changes that occur during the processing of water-boiled salted duck (WSD). Only 110 PL molecular species have been identified in raw duck meat, while a total of 119 PL molecular species were identified during processing, including 33 phosphatidylcholines, 22 phosphatidylethanolamines, 13 phosphatidylglycerols, 18 phosphatidylinositols and 33 phosphatidylserines. Most of the content of PL molecular species gradually decreased during processing, while the content of most of the lysophospholipids (LPLs) increased. After reaching a maximum, the LPLs were obviously reduced during the 3 d of dry-ripening. The results showed that processing techniques, such as dry-curing, dry-ripening and boiling, had a significant effect on the changes in the PLs in WSD. We further screened 10 PL molecular markers, which can be used to distinguish different operating units.
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http://dx.doi.org/10.1016/j.foodres.2020.109064DOI Listing
June 2020
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