Publications by authors named "Qiuyun Fu"

16 Publications

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Corrigendum to "Fabrication of BiFeO-g-CN-WO Z-scheme heterojunction as highly efficient visible-light photocatalyst for water reduction and 2,4-dichlorophenol degradation: Insight mechanism" [J. Hazard. Mater. 397 (2020) 122708].

J Hazard Mater 2021 Aug 7;421:126772. Epub 2021 Aug 7.

Engineering Research Center for Functional Ceramics of the Ministry of Education, School of Optical and Electronic Information, Huazhong University of Science and Technology, Wuhan 430074, PR China; China-EU Institute for Clean and Renewable Energy, Huazhong University of Science and Technology, Wuhan 430074, PR China.

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http://dx.doi.org/10.1016/j.jhazmat.2021.126772DOI Listing
August 2021

A Prelithiation Separator for Compensating the Initial Capacity Loss of Lithium-Ion Batteries.

ACS Appl Mater Interfaces 2021 Aug 3;13(32):38194-38201. Epub 2021 Aug 3.

State Key Laboratory of Material Processing and Die & Mold Technology, School of Materials Science and Engineering, Huazhong University of Science and Technology, Wuhan, Hubei 430074, China.

Lithium loss during the initial charge process inevitably reduces the capacity and energy density of lithium-ion batteries. Cathode additives are favored with respect to their controllable prelithiation degree and scalable application; however, the insulating nature of their delithiation products retards electrode reaction kinetics in subsequent cycles. Herein, we propose a prelithiation separator by modifying a commercial separator with a LiS/Co nanocomposite to compensate for the initial capacity loss. The LiS/Co coating layer extracts active lithium ion during the charge process and shows a delithiation capacity of 993 mA h g. When paired with a LiFePO|graphite full cell, the reversible capacity is increased from 112.6 to 150.3 mA h g, leading to a 29.5% boost in the energy density. The as-prepared pouch cell also demonstrates a stable cycling performance. The excellent electrochemical performance and the scalable production of the prelithiation separator reveal its great potential in lithium-ion battery industry application.
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http://dx.doi.org/10.1021/acsami.1c06703DOI Listing
August 2021

A rational design of g-CN-based ternary composite for highly efficient H generation and 2,4-DCP degradation.

J Colloid Interface Sci 2021 Oct 20;599:484-496. Epub 2021 Apr 20.

Engineering Research Center for Functional Ceramics of the Ministry of Education, School of Optical and Electronic Information, Wuhan National Laboratory for Optoelectronics, Huazhong University of Science and Technology, Wuhan 430074, PR China; Wuhan National Laboratory for Optoelectronics, Huazhong University of Science and Technology, Wuhan 430074, PR China. Electronic address:

In this work, g-CN based ternary composite (CeO/CN/NH-MIL-101(Fe)) has been fabricated via hydrothermal and wet-chemical methods. The composite showed superior photoactivities for HO reduction to produce H and 2,4-dichlorophenol (2,4-DCP) degradation. The amount of H evolved over the composite under visible and UV-visible irradiations is 147.4 µmol·g·h and 556.2 µmol·g·h, respectively. Further, the photocatalyst degraded 87% of 2,4-DCP in 2 hrs under visible light irradiations. The improved photoactivities are accredited to the synergistic-effects caused by the proper band alignment with close interfacial contact of the three components that significantly promoted charge transfer and separation. The 2,4-DCP degradation over the composite is dominated by OH radical rather than h and O as investigated by scavenger trapping experiments. This is further supported by the electron para-magnetic resonance (EPR) study. This work provides new directions for the development of g-CN based highly efficient ternary composite materials for clean energy generation and pollution control.
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http://dx.doi.org/10.1016/j.jcis.2021.04.049DOI Listing
October 2021

A deep learning algorithm for detection of oral cavity squamous cell carcinoma from photographic images: A retrospective study.

EClinicalMedicine 2020 Oct 23;27:100558. Epub 2020 Sep 23.

Department of Oral and Maxillofacial Surgery, School and Hospital of Stomatology, Wuhan University, Wuhan, Hubei 430079, China.

Background: The overall prognosis of oral cancer remains poor because over half of patients are diagnosed at advanced-stages. Previously reported screening and earlier detection methods for oral cancer still largely rely on health workers' clinical experience and as yet there is no established method. We aimed to develop a rapid, non-invasive, cost-effective, and easy-to-use deep learning approach for identifying oral cavity squamous cell carcinoma (OCSCC) patients using photographic images.

Methods: We developed an automated deep learning algorithm using cascaded convolutional neural networks to detect OCSCC from photographic images. We included all biopsy-proven OCSCC photographs and normal controls of 44,409 clinical images collected from 11 hospitals around China between April 12, 2006, and Nov 25, 2019. We trained the algorithm on a randomly selected part of this dataset (development dataset) and used the rest for testing (internal validation dataset). Additionally, we curated an external validation dataset comprising clinical photographs from six representative journals in the field of dentistry and oral surgery. We also compared the performance of the algorithm with that of seven oral cancer specialists on a clinical validation dataset. We used the pathological reports as gold standard for OCSCC identification. We evaluated the algorithm performance on the internal, external, and clinical validation datasets by calculating the area under the receiver operating characteristic curves (AUCs), accuracy, sensitivity, and specificity with two-sided 95% CIs.

Findings: 1469 intraoral photographic images were used to validate our approach. The deep learning algorithm achieved an AUC of 0·983 (95% CI 0·973-0·991), sensitivity of 94·9% (0·915-0·978), and specificity of 88·7% (0·845-0·926) on the internal validation dataset ( = 401), and an AUC of 0·935 (0·910-0·957), sensitivity of 89·6% (0·847-0·942) and specificity of 80·6% (0·757-0·853) on the external validation dataset ( = 402). For a secondary analysis on the internal validation dataset, the algorithm presented an AUC of 0·995 (0·988-0·999), sensitivity of 97·4% (0·932-1·000) and specificity of 93·5% (0·882-0·979) in detecting early-stage OCSCC. On the clinical validation dataset ( = 666), our algorithm achieved comparable performance to that of the average oral cancer expert in terms of accuracy (92·3% [0·902-0·943] 92.4% [0·912-0·936]), sensitivity (91·0% [0·879-0·941] 91·7% [0·898-0·934]), and specificity (93·5% [0·909-0·960] 93·1% [0·914-0·948]). The algorithm also achieved significantly better performance than that of the average medical student (accuracy of 87·0% [0·855-0·885], sensitivity of 83·1% [0·807-0·854], and specificity of 90·7% [0·889-0·924]) and the average non-medical student (accuracy of 77·2% [0·757-0·787], sensitivity of 76·6% [0·743-0·788], and specificity of 77·9% [0·759-0·797]).

Interpretation: Automated detection of OCSCC by deep-learning-powered algorithm is a rapid, non-invasive, low-cost, and convenient method, which yielded comparable performance to that of human specialists and has the potential to be used as a clinical tool for fast screening, earlier detection, and therapeutic efficacy assessment of the cancer.
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http://dx.doi.org/10.1016/j.eclinm.2020.100558DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7599313PMC
October 2020

Fabrication of BiFeO-g-CN-WO Z-scheme heterojunction as highly efficient visible-light photocatalyst for water reduction and 2,4-dichlorophenol degradation: Insight mechanism.

J Hazard Mater 2020 Oct 20;397:122708. Epub 2020 Apr 20.

Engineering Research Center for Functional Ceramics of the Ministry of Education, School of Optical and Electronic Information, Huazhong University of Science and Technology, Wuhan 430074, PR China; China-EU Institute for Clean and Renewable Energy, HuazhongUniversity of Science and Technology, Wuhan 430074, PR China. Electronic address:

In this work, a Z-scheme BiFeO-g-CN-WO (BFO-CN-WO) photocatalyst has been synthesized via a wet chemical method and utilized in photocatalysis for hydrogen generation and 2,4-dichlorophenol (2,4-DCP) degradation under visible light irradiation. The resultant photocatalyst showed 90 μmol·h g H evolution activity and 63% 2,4-DCP degradation performance, which is 12 and 4.2 times higher than the pristine g-CN respectively. The fascinating photocatalytic performance is attributed to the strong interfacial contact between g-CN and the coupled BiFeO and WO component, which greatly improved the visible light absorption and charge carriers' separation. The designed Z-scheme heterojunction is a successful strategy for enhancing the separation efficiency of photo-induced charge carriers at the interface while retaining outstanding redox ability. During 2,4-DCP degradation, LC/MS technique was used to detect the reaction intermediates. According to the LC/MS results, several new intermediates such as 2,3-dichloro-6-(2,4-dichlorophenoxy)phenol (m/z = 306), 2,4-dichlorophenyl hydrogen carbonate (m/z = 207), 2,4-dichlorobenzen-1,3-diol (m/z = 177) and phenyl hydrogen carbonate (m/z = 137) were detected. Based on these intermediates, 2,4-DCP degradation pathway is proposed. The fluorescence (FL) and electron paramagnetic resonance (EPR) results reveal that the •OH plays an important role in the 2,4-DCP degradation. The fabricated photocatalyst can be utilized in the field of photocatalysis for practical applications.
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http://dx.doi.org/10.1016/j.jhazmat.2020.122708DOI Listing
October 2020

Experimental and DFT Studies of Au Deposition Over WO/g-CN Z-Scheme Heterojunction.

Nanomicro Lett 2019 Dec 19;12(1). Epub 2019 Dec 19.

Engineering Research Center for Functional Ceramics of the Ministry of Education, School of Optical and Electronic Information, Huazhong University of Science and Technology, Wuhan, 430074, People's Republic of China.

A typical Z-scheme system is composed of two photocatalysts which generate two sets of charge carriers and split water into H and O at different locations. Scientists are struggling to enhance the efficiencies of these systems by maximizing their light absorption, engineering more stable redox couples, and discovering new O and H evolutions co-catalysts. In this work, Au decorated WO/g-CN Z-scheme nanocomposites are fabricated via wet-chemical and photo-deposition methods. The nanocomposites are utilized in photocatalysis for H production and 2,4-dichlorophenol (2,4-DCP) degradation. It is investigated that the optimized 4Au/6% WO/CN nanocomposite is highly efficient for production of 69.9 and 307.3 µmol h g H gas, respectively, under visible-light (λ > 420 nm) and UV-visible illumination. Further, the fabricated 4Au/6% WO/CN nanocomposite is significant (i.e., 100% degradation in 2 h) for 2,4-DCP degradation under visible light and highly stable in photocatalysis. A significant 4.17% quantum efficiency is recorded for H production at wavelength 420 nm. This enhanced performance is attributed to the improved charge separation and the surface plasmon resonance effect of Au nanoparticles. Solid-state density functional theory simulations are performed to countercheck and validate our experimental data. Positive surface formation energy, high charge transfer, and strong non-bonding interaction via electrostatic forces confirm the stability of 4Au/6% WO/CN interface.
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http://dx.doi.org/10.1007/s40820-019-0345-2DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7770730PMC
December 2019

A BiTe Topological Insulator as a New and Outstanding Counter Electrode Material for High-Efficiency and Endurable Flexible Perovskite Solar Cells.

ACS Appl Mater Interfaces 2019 Dec 17;11(51):47868-47877. Epub 2019 Dec 17.

School of Optical and Electronic Information, Engineering Research Center for Functional Ceramics of the Ministry of Education , Huazhong University of Science and Technology , Wuhan 430074 , P. R. China.

Inverted flexible perovskite solar cells (PSCs) typically employ expensive metals as the counter electrodes, which are brittle and corrodible by perovskite, leading to a sharp performance drop under continuous bending, air exposure, thermal stress, or light illumination and eventually retard the commercialization. Herein, a low-cost BiTe counter electrode was employed by using a simple thermal evaporation process. The resultant device achieved an excellent power conversion efficiency of 18.16%, which was among the highest reported efficiencies, much higher than the reference Ag PSC (15.90%). The improvement should be attributed to the intrinsic suppressed electron backscattering in a BiTe topological insulator. Simultaneously, the BiTe device obtained a significantly improved mechanical flexibility and long-term operational stability. The present strategy will help to open up a new avenue for future commercialization of flexible photovoltaic applications.
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http://dx.doi.org/10.1021/acsami.9b15320DOI Listing
December 2019

Photodegradation of 2,4-dichlorophenol and rhodamine B over n-type ZnO/p-type BiFeO heterojunctions: detailed reaction pathway and mechanism.

Environ Sci Pollut Res Int 2019 Jun 27;26(17):17696-17706. Epub 2019 Apr 27.

China-EU Institute for Clean and Renewable Energy, Huazhong University of Science and Technology, Wuhan, 430074, People's Republic of China.

The development of new technologies for efficient degradation of pollutant has been an increasing demand in the globe due to the serious environmental issues. Herein, we report n-type ZnO/p-type BiFeO composites as highly efficient visible light nanophotocatalysts prepared via a wet chemical solution method. Based on the measurements of OH-related fluorescence (FL) spectra, photoluminescence (PL) spectra, photoelectrochemical I-V curves, and electrochemical impedance spectra (EIS), it is demonstrated that the photo-induced charge carrier (electron-hole pairs) in the as-prepared n-type ZnO/p-type BiFeO composites with proper amount of the coupled ZnO (10% by mass) exhibits high separation compared with the bare BiFeO (BFO) nanoparticles. This is well responsible for the superior visible light photocatalytic performance of the composites for 2,4-dichlorophenol (2,4-DCP) and rhodamine B (RhB) degradation. It is confirmed by means of scavenger test and liquid chromatography-tandem mass spectrometry (LC/MS) analysis of the intermediate products that OH is the pre-dominant oxidant involved in the degradation of 2,4-DCP. A detailed reaction pathway for 2,4-dichlorophenol degradation over the amount-optimized ZnO/BFO composite is proposed mainly based on the LC/MS product ions. This work will provide a feasible route to design and develop BFO-based highly efficient visible light-active photocatalysts for environmental purification and could be extended to other visible light-active semiconductor materials.
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http://dx.doi.org/10.1007/s11356-019-05079-0DOI Listing
June 2019

Improving the Performance and Reproducibility of Inverted Planar Perovskite Solar Cells Using Tetraethyl Orthosilicate as the Antisolvent.

ACS Appl Mater Interfaces 2019 Jan 17;11(4):3909-3916. Epub 2019 Jan 17.

School of Optical and Electronic Information, Engineering Research Center for Functional Ceramics of the Ministry of Education , Huazhong University of Science and Technology , Wuhan 430074 , P. R. China.

Antisolvent-assisted crystallization has been extensively used for perovskite solar cells (PSCs), although this approach has a fatal drawback, low reproducibility, originating from the extremely harsh operating conditions of the current antisolvents. As a result, only skilled technicians are qualified to be scheduled to prepare perovskite thin films to fabricate high-efficiency devices, which lowers the pace of progress of PSCs. Besides, the most popular antisolvents toluene (TL) and chlorobenzene (CB) are highly toxic and carcinogenic. On account of these, we tried to develop a low hazardous antisolvent that enabled us to achieve highly efficient and highly reproducible PSCs. Herein, tetraethyl orthosilicate (TEOS) was employed in the inverted NiO -based planar PSC for engineering an efficient perovskite layer, achieving a power conversion efficiency of 17.02% on glass substrates and 14.49% on flexible polymer substrates with negligible hysteresis, which even outperformed TL and CB. More importantly, TEOS PSCs exhibited much higher reproducibility than that of their counterparts. These desirable features should be ascribed to the higher-quality perovskite films with larger grain size, reduced density of defects, and thus smoother carrier transportation and slower carrier recombination. This work drives another step toward industrial-scale commercialization of PSCs and also paves the way for environmentally friendly photovoltaic applications.
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http://dx.doi.org/10.1021/acsami.8b18402DOI Listing
January 2019

Fast and Accurate Finite Transducer Analysis Method for Wireless Passive Impedance-Loaded SAW Sensors.

Sensors (Basel) 2018 Nov 16;18(11). Epub 2018 Nov 16.

Institute of Acoustics, Chinese Academy of Sciences, 21 North 4th Ring Road, Haidian District, Beijing 100190, China.

An accurate and fast simulation tool plays an important role in the design of wireless passive impedance-loaded surface acoustic wave (SAW) sensors which have received much attention recently. This paper presents a finite transducer analysis method for wireless passive impedance-loaded SAW sensors. The finite transducer analysis method uses a numerically combined finite element method-boundary element method (FEM/BEM) model to analyze non-periodic transducers. In non-periodic transducers, FEM/BEM was the most accurate analysis method until now, however this method consumes central processing unit (CPU) time. This paper presents a faster algorithm to calculate the bulk wave part of the equation coefficient which usually requires a long time. A complete non-periodic FEM/BEM model of the impedance sensors was constructed. Modifications were made to the final equations in the FEM/BEM model to adjust for the impedance variation of the sensors. Compared with the conventional method, the proposed method reduces the computation time efficiently while maintaining the same high degree of accuracy. Simulations and their comparisons with experimental results for test devices are shown to prove the effectiveness of the analysis method.
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http://dx.doi.org/10.3390/s18113988DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6263883PMC
November 2018

Highly efficient degradation of 2,4-dichlorophenol over CeO/g-CN composites under visible-light irradiation: Detailed reaction pathway and mechanism.

J Hazard Mater 2019 02 31;364:635-644. Epub 2018 Oct 31.

Engineering Research Center for Functional Ceramics of the Ministry of Education, School of Optical and Electronic Information, Huazhong University of Science and Technology, Wuhan, 430074, PR China. Electronic address:

Herein, we report for the first time the highly efficient degradation of 2,4-dichlorophenol (2,4-DCP) over CeO/g-CN composites (xCeO/CN) prepared via wet-chemical solution method. It is shown that the resultant nanocomposites with a proper mass ratio percentage (15%) of CeO coupled exhibit greatly enhanced visible-light activity for 2,4-dichlorophenol (2,4-DCP) degradation compared to the bare g-CN. From photoluminescence (PL) and Fluorescence (FL) results, it is suggested that enhanced photo-degradation is attributed to the significantly improved charge separation and transfer as a result of the proper band alignments between g-CN and CeO components. Further, from radical trapping experiments, it is confirmed that hydroxyl radicals (OH) are the predominant oxidants involved in the degradation of 2,4-DCP over CeO/CN composites. Furthermore, a possible reaction pathway and detailed photocatalytic mechanism for 2,4-DCP degradation is proposed mainly based on the detected liquid chromatography tandem mass spectrometry (LC-MS) intermediate products, that readily transform into CO and HO. This work would help researchers to deeply understand the reaction mechanism of 2,4-DCP and would provide feasible routes to fabricate g-CN-based highly efficient photocatalysts for environmental remediation.
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http://dx.doi.org/10.1016/j.jhazmat.2018.10.088DOI Listing
February 2019

Multiple Interfacial [email protected]/P(VDF-HFP) Core-Shell-Matrix Films with Internal Barrier Layer Capacitor (IBLC) Effects and High Energy Storage Density.

ACS Appl Mater Interfaces 2017 Nov 10;9(46):40792-40800. Epub 2017 Nov 10.

Institute of Huazhong University of Science and Technology , 9 Yuexingsandao, Nanshan District, Shenzhen 518000, P. R. China.

Flexible nanocomposites composed of high dielectric constant fillers and polymer matrix have shown great potential for electrostatic capacitors and energy storage applications. To obtain the composited material with high dielectric constant and high breakdown strength, multi-interfacial composited particles, which composed of conductive cores and insulating shells and possessed the internal barrier layer capacitor (IBLC) effect, were adopted as fillers. Thus, [email protected] core-shell particles were prepared and loaded into the poly(vinylidene fluoride-co-hexafluoropropylene) (P(VDF-HFP)) polymer matrix. As the mass fraction of core-shell fillers increased from 2.5 wt % to 30 wt %, the dielectric constant of the films increased, while the loss tangent remained at a low level (<0.05 at 1 kHz). Both high electric displacement and high electric breakdown strength were achieved in the films with 10 wt % core-shell fillers loaded. The maximum energy storage density of 7.018 J/cm was measured at 2350 kV/cm, which shows significant enhancement than those of the pure P(VDF-HFP) films and analogous composited films with converse insulating-conductive core-shell fillers. A Maxwell-Wagner capacitor model was also adopted to interpret the efficiency of IBLC effects on the suppressed loss tangent and the superior breakdown strength. This work explored an effective approach to prepare dielectric nanocomposites for energy storage applications experimentally and theoretically.
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http://dx.doi.org/10.1021/acsami.7b10923DOI Listing
November 2017

Physically flexible, rapid-response gas sensor based on colloidal quantum dot solids.

Adv Mater 2014 May 22;26(17):2718-24, 2617. Epub 2014 Jan 22.

School of Optical and Electronic Information, Huazhong University of Science and Technology, 1037 Luoyu Road, Wuhan, Hubei, 430074, P. R. China.

A gas sensor based on PbS colloidal quantum dots (CQDs) is constructed on a paper substrate, yielding flexible, rapid-response NO₂ gas sensors, fabricated from the solution phase. The devices are highly sensitive and fully recoverable at room temperature, which is attributed to the excellent access of gas molecules to the CQD surface, realized by surface ligand removal, combined with the desirable binding energy of NO₂ with the PbS CQDs.
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http://dx.doi.org/10.1002/adma.201304366DOI Listing
May 2014

Effect of storage conditions on the extraction of PCR-quality genomic DNA from saliva.

Clin Chim Acta 2004 May;343(1-2):191-4

Department of Community, Occupational and Family Medicine (MD3), Faculty of Medicine, National University of Singapore, 16, Medical Drive, Singapore 117597, Singapore.

Background: Saliva is a potentially useful source of genomic DNA for genetic studies since it can be collected in a painless and non-invasive manner. We sought to determine whether different storage conditions of saliva samples impact our ability to extract genomic DNA that is of sufficient quality for use in the polymerase chain reaction (PCR).

Methods: Saliva was collected from healthy volunteers and 2-ml aliquots subjected to different storage conditions: S1--washing of saliva using phosphate-buffered saline (PBS) and extraction of DNA on the same day of collection; S2--washing and centrifugation to yield a pellet, which was stored at-70 degrees C for 1 week prior to DNA extraction; S3--storage of whole saliva at 4 degrees C for 7 days, followed by washing and extraction of DNA; S4--storage at 4 degrees C for 7 days, followed by washing and pellet formation. The pellet was stored at -70 degrees C for 1 month before extraction of the DNA; S5--storage at-70 degrees C for 1 month, followed by washing and extraction of DNA. DNA yield and purity was determined by spectrophotometry at 260 and 280 nm. Twenty nanograms of genomic DNA was used for the polymerase chain reaction, and the resulting PCR band was captured by digital photography and quantified.

Results: The amounts of DNA extracted from 2 ml of saliva varied widely under the different storage conditions, while purity of the DNA extraction, based on OD(260/280) ratios, was good and comparable. PCR resulted in the presence of a single specific product of the correct size from all samples regardless of saliva storage conditions. Quantification of PCR bands showed significant differences between the various storage conditions (P<0.05). Compared to S1 samples, PCR bands from conditions S2 and S3 were not as strong, while those amplified from S4 and S5 samples were the weakest. Post-hoc analyses showed that the means for conditions S4 and S5 were significantly different from S1-S3. Qualitatively similar results were obtained when the PCR experiment was repeated.

Conclusions: Saliva can act as a useful source of genomic DNA, even when stored under less than optimal conditions.
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http://dx.doi.org/10.1016/j.cccn.2004.01.013DOI Listing
May 2004

Effects of storage time on stability of salivary immunoglobulin A and lysozyme.

Clin Chim Acta 2003 Dec;338(1-2):131-4

Department of Community, Occupational and Family Medicine, Faculty of Medicine (MD3), National University of Singapore, 16, Medical Drive, Singapore 117597, Singapore.

Background: In many research settings, storage of samples prior to analysis is unavoidable. This study investigates the effects of storage time on stability of salivary immunoglobulin A (IgA) and lysozyme.

Methods: Saliva samples were obtained from 30 healthy adults. Each sample was divided into five aliquots and stored at -30 degrees C until analysis. The samples were measured for IgA and lysozyme concentrations after 1, 2, 3, 8 and 12 months of storage using enzyme-linked immunosorbent assay.

Results: There was a decline in the concentrations of IgA and lysozyme with increasing storage time. Repeated measures analyses for both salivary IgA and lysozyme showed a significant difference after 8 months of storage as compared to the 1st month (p<0.05). IgA levels decreased significantly with % change in majority of the samples >10% after storage for 8 months or more. A similar pattern was observed for lysozyme with % change in majority of the samples >14% levels when the samples were assayed at 8th month and beyond (mean% change+/-S.D.>14%).

Conclusion: Salivary IgA and lysozyme concentrations remain stable for up to 3 months when stored at -30 degrees C. These findings have important implications with regard to measurement validity of salivary biomarkers research.
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http://dx.doi.org/10.1016/j.cccn.2003.08.012DOI Listing
December 2003
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