Publications by authors named "Kadir Aslan"

110 Publications

Metal-Assisted and Microwave-Accelerated Decrystallization: An Alternative Approach to Potential Treatment of Crystal Deposition Diseases.

Clin Arch Bone Jt Dis 2017 13;1(1). Epub 2017 Oct 13.

Department of Civil Engineering, Morgan State University, USA.

Gout is a painful and prevalent crystal deposition disease caused by the overproduction of Uric Acid (UA) in the body and the atypical deposition in human synovial joints as Monosodium Urate Monohydrate (MSUM). Conventional treatments, such as NSAIDs, cyclooxygenase-2 inhibitors, and systemic glucocorticoids often present harmful side-effects and are short-lived. Long-term therapies including xanthine oxidase inhibitors and the use of uricosuric agents have been developed and aim to lower the UA serum levels in the body. As regards to post-crystals deposition, our research laboratory recently proposed and demonstrated the use of the Metal-Assisted and Microwave-Accelerated Decrystallization (MAMAD) technique for the breakdown of organic and biological crystals on planar surfaces. The MAMAD technique is based on the combined use of microwave heating and Au NPs in solution. The interactions of the Au NPs with microwave's electromagnetic field result in an increase in the kinetic energy of Au NPs, and subsequently, an increase in the collisions with target crystals placed on planar surfaces leading to rapid crystal breakdown. In this regard, our laboratory aims to develop the MAMAD technique as an alternative treatment for crystal deposition diseases, particularly gout, with minimal invasion and side-effects as compared to current treatments. In this review article, we will summarize our previous findings and provide additional data detailing the effectiveness of the MAMAD technique as a rapid and efficient method for the breakdown of gout related crystals and L-alanine crystals (a model crystal).
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http://dx.doi.org/10.23937/cabjd-2017/1710002DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8025928PMC
October 2017

Use of surface plasmon-coupled emission for enhancing light transmission through Top-Emitting Organic Light Emitting Diodes.

Thin Solid Films 2008 Feb 13;516(8):1977-1983. Epub 2007 Jun 13.

Industrial Science and Technology Network Inc., 2101 Pennsylvania Avenue, York, PA, 17404, USA.

In this paper, we perform surface plasmon-coupled emission studies on Rhodamine 6G molecules embedded in a corrugated structure of a thin film composed of fluorinated silica particles, and a binding medium. Our results show enhancements of photoluminescence due to surface corrugation. By varying the size of the fluorinated silica nanoparticles we were able to control the surface correlation length scale of the corrugated surface structure. It was found that the coupling efficiency of the directional light emission is strongly correlated to the surface morphology, particularly the surface correlation length, of the corrugated dielectric structure. This substantial enhancement of signal could potentially be utilized in Organic Light Emitting Diode devices to enhance the light emission and transmission through a thin silver layer which can also serve as the cathode in Top-Emitting Organic Light Emitting Diodes.
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http://dx.doi.org/10.1016/j.tsf.2007.05.081DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8022332PMC
February 2008

Impact of Zero-Valent Iron Nanoparticles on Transesterified Lipids and Fatty Acid Methyl Esters.

ACS Omega 2020 Jun 20;5(21):12166-12173. Epub 2020 May 20.

Department of Biology, Morgan State University, 1700 East Cold Spring Lane, Baltimore, Maryland 21251, United States.

Efforts to enhance the transformative potential of biofuels is an important step to achieving an environment-friendly and sustainable energy source. is an ideal third-generation biofuel agent due to its ability to produce lipids and desirable essential fatty acids. In this study, the impact of Nanofer 25s nanoscale zero-valent iron nanoparticles (nZVIs) on total lipid content and fatty acid composition of strains SF33 and B481 was investigated. We observed significant increases ( < 0.05) in the growth of treated with 0.2-1.6 mg L Nanofer 25s, indicating that trace concentrations of nZVIs were not toxic to the organism. Chlorophyll , carotenoids, and phycobiliprotein levels were not altered in treated with nZVIs ranging from 0.4 to 1.6 mg L, confirming that these concentrations did not negatively impact photosynthetic efficacy. In addition, Nanofer 25s ranging from 0.2 to 1.6 mg L had an optimal impact on SF33 and B481 total lipid content. We identified significant increases in unsaturated fatty acid methyl esters (FAMEs) from Nanofer 25s-treated transesterified lipids. Theoretical chemical and physical biofuel properties revealed a product with elevated cetane number and oxidative stability for both strains. Scanning electron microscopy and energy-dispersive X-ray spectroscopy validated the localization of nZVIs. Our findings indicate that Nanofer 25s nZVIs significantly enhance total lipid content and essential FAMEs, thus offering a promising approach to augment the potential of the cyanobacterium as a large-scale biofuel agent.
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http://dx.doi.org/10.1021/acsomega.0c00566DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7271364PMC
June 2020

Nanoparticle-mediated Impact on Growth and Fatty Acid Methyl Ester Composition in the Cyanobacterium .

Bioenergy Res 2019 Jun 8;12:409-418. Epub 2019 Mar 8.

Department of Biology, Morgan State University, 1700 East Cold Spring Lane, Baltimore, Maryland 21251, United States.

Insufficient light supply is a major limitation in cultivation of cyanobacteria for scaled up biofuel production and other biotechnological applications, which has driven interest in nanoparticle-mediated enhancement of cellular light capture. In the present study, wild type (Fd33) and halotolerant (HSF33-2) strains were grown in solution with 20, 100, and 200 nm-diameter gold nanoparticles (AuNPs) to determine their impact on biomass accumulation, pigmentation, and fatty acid methyl ester (FAME) production. Results revealed a significant increase in growth of Fd33 (0.244 ± 0.006) and HSF33-2 (0.112 ± 0.003) when treated with 200 nm AuNPs. In addition, we observed a significant increase in chlorophyll accumulation in 200 nm AuNP-treated Fd33 (25.7%) and HSF33-2 (36.3%) indicating that NPs enhanced photosynthetic pigmentation. We did not observe any alteration in FAME composition and biodiesel properties of transesterified lipids among all AuNP treatments. Interactions between and AuNPs were visualized using scanning electron microscopy. Energy dispersive X-ray spectroscopy confirmed the presence of AuNPs outside cells with aggregation in high cell density locales. Our findings indicate that nanotechnological approaches could significantly enhance growth of the organism with no negative effect on FAME-derived biodiesel properties, thus augmenting as a potential biofuel agent.
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http://dx.doi.org/10.1007/s12155-019-09966-9DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6980354PMC
June 2019

Rapid Sensing of Biological and Environmental Analytes Using Microwave-Accelerated Bioassays and a MATLAB Application.

Nano Biomed Eng 2019 15;11(2):111-123. Epub 2019 Apr 15.

Department of Civil Engineering, Morgan State University, 1700 East Cold Spring Lane, Baltimore, Maryland 21251, USA.

We report a method for rapid detection and analysis of biological and environmental analytes by microwave-accelerated bioassays (MABs) and a novel MATLAB-based image processing of colorimetric signals. In this regard, colorimetric bioassays for histidine-rich protein 2 (HRP-2) and microcystin-leucine arginine (MC-LR) toxin were carried out using MABs and without microwave heating (i.e, gold standard bioassays). Our MATLAB-based detection method is based on the direct correlation of color intensity of a solution calculated from images captured with a smartphone with the concentration of the biomolecule of interest using a MATLAB code developed in-house. We demonstrated that our MATLAB-based detection method can yield bioassay sensitivity comparable to the colorimetric gold standard tool, i.e., UV-Visible spectroscopy. In addition, colorimetric bioassay time for the HRP-2 assay (used in malaria diagnosis) and colorimetric MC-LR bioassay (used in MCLR toxin diagnosis) was reduced from up to 2 hours at room temperature without microwave heating to 15 minutes using the MABs technique.
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http://dx.doi.org/10.5101/nbe.v11i2.p111-123DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6764453PMC
April 2019

Metal-Assisted and Microwave-Accelerated Decrystallization of Pseudo-Tophus in Synthetic Human Joint Models.

ACS Omega 2019 Feb;4(2):4417-4428

Department of Civil Engineering, Department of Physics and Engineering Physics, and Department of Biology, Morgan State University, 1700 East Cold Spring Lane, Baltimore, Maryland 21251, United States.

In this paper, we tested a hypothesis that the metal-assisted and microwave-accelerated decrystallization (MAMAD) technique, based on the combined use of low-power medical microwave heating (MWH) and gold nanoparticles (Au NPs), can be used to decrystallize laboratory-prepared monosodium urate monohydrate crystal aggregate (pseudo-tophus) placed in three-dimensional (3D) synthetic human joint models. To simulate a potential treatment of chronic tophaceous gout using the MAMAD technique, we used three different 3D synthetic human joint models and assessed the percent mass reduction (PMR, i.e., decrystallization) of pseudo-tophus and microwave-induced synthetic skin patch damage after MAMAD sessions (a MAMAD session = 120 s of MWH in the presence of Au NPs). Our three synthetic joint models are: Model 1: Application of seven MAMAD sessions in a closed synthetic joint with a pseudo-bursa containing a pseudo-tophus submerged in a solution of 20 nm Au NPs followed by dehydration of pseudo-tophus after each MAMAD session to assess PMR. Model 2: Application of seven MAMAD sessions in a closed or open synthetic joint with a pseudo-bursa containing a pseudo-tophus submerged in a solution of Au NPs followed by intermittent dehydration of pseudo-tophus after seven MAMAD sessions to assess PMR. Model 3: Application of 18 MAMAD sessions in a rotated closed synthetic joint (three sides are heated separately) with a pseudo-bursa containing a pseudo-tophus submerged in a solution of Au NPs followed by dehydration after every three MAMAD sessions to assess PMR. After a single MAMAD session, pseudo-tophus exposed to MWH and Au NPs had an average PMR of 8.30% (up to an overall PMR of 15%), and microwave-induced damage to the synthetic skin can be controlled by the use of a sacrificial skin sample and by adjusting the duration and the number of the MAMAD sessions. Computational electromagnetic simulations predict a 10% absorption of electric field by the pseudo-tophus placed in the synthetic joint models, which led us to conclude that a medical microwave source with higher power than 20 W can potentially be used with the MAMAD technique.
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http://dx.doi.org/10.1021/acsomega.8b03497DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6407899PMC
February 2019

Individually grown cobalt nanowires as magnetic force microscopy probes.

Appl Phys Lett 2018 Feb;112(9):092401

Department of Physics, Morgan State University, 1700 East Cold Spring Lane, Baltimore, Maryland 21215, USA.

AC electric fields were utilized in the growth of individual high-aspect ratio cobalt nanowires from simple salt solutions using the Directed Electrochemical Nanowire Assembly method. Nanowire diameters were tuned from the submicron scale to 40 nm by adjusting the AC voltage frequency and the growth solution concentration. The structural properties of the nanowires, including shape and crystallinity, were identified using electron microscopy. Hysteresis loops obtained along different directions of an individual nanowire using vibrating sample magnetometry showed that the magnetocrystalline anisotropy energy has the same order of magnitude as the shape anisotropy energy. Additionally, the saturation magnetization of an individual cobalt nanowire was estimated to be close to the bulk single crystal value. A small cobalt nanowire segment was grown from a conductive atomic force microscope cantilever tip that was utilized in magnetic force microscopy (MFM) imaging. The fabricated MFM tip provided moderate quality magnetic images of an iron-cobalt thin-film sample.
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http://dx.doi.org/10.1063/1.4997310DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5826737PMC
February 2018

Microwave Heating of Crystals with Gold Nanoparticles and Synovial Fluid under Synthetic Skin Patches.

ACS Omega 2017 Sep 20;2(9):5992-6002. Epub 2017 Sep 20.

Department of Biology and Department of Chemistry, Morgan State University, 1700 East Cold Spring Lane, Baltimore, Maryland 21251, United States.

Gout is a disease with elusive treatment options. Reduction of the size of l-alanine crystals as a model crystal for gouty tophi with the use of a monomode solid-state microwave was examined as a possible therapeutic aid. The effect of microwave heating on l-alanine crystals in the presence of gold nanoparticles (Au NPs) in solution and synovial fluid (SF) in a plastic pouch through a synthetic skin patch was investigated. In this regard, three experimental paradigms were employed: Paradigm 1 includes the effect of variable microwave power (5-10 W) and variable heating time (5-60 s) and Au NPs in water (20 nm size, volume of 10 μL) in a plastic pouch (1 × 2 cm in size). Paradigm 2 includes the effect of a variable volume of 20 nm Au NPs in a variable volume of SF up to 100 μL in a plastic pouch at a constant microwave power (10 W) for 30 s. Paradigm 3 includes the effect of constant microwave power (10 W) and microwave heating time (30 s), constant volume of Au NPs (100 μL), and variable size of Au NPs (20-200 nm) placed in a plastic pouch through a synthetic skin patch. In these experiments, an average of 60-100% reduction in the size of an l-alanine crystal (initial size = 450 μm) without damage to the synthetic skin or increasing the temperature of the samples beyond the physiological range was reported.
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http://dx.doi.org/10.1021/acsomega.7b00816DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5623947PMC
September 2017

Metal oxide surfaces for enhanced colorimetric response in bioassays.

Colloids Surf B Biointerfaces 2017 Jun 18;154:331-340. Epub 2017 Mar 18.

Department of Chemistry, Morgan State University, 1700 East Cold Spring Lane, Baltimore, MD 21251, USA. Electronic address:

Physical stability of metal nanoparticle films on planar surfaces can be increased by employing surface modification techniques and/or type of metal nanoparticles. Subsequently, the enzymatic response of colorimetric bioassays can be increased for improved dynamic range for the detection of biomolecules. Using a model bioassay b-BSA, three planar platforms (1) poly (methyl methacrylate) (PMMA) with silver thin films (STFs), (2) silver nanowires (Ag NWs) on paper and (3) indium tin oxide (ITO) on polyethylene terephthalate (PET) were evaluated to investigate the extent of increase in the colorimetric signal. Bioassays for b-BSA and Ki-67 antigen (a real-life bioassay) in buffer were performed using microwave heating (total assay time is 25-30min) and at room temperature (a control experiment, total assay time is 3h). Model bioassays showed that STFs were removed from the surface during washing steps and the extent of ITO remained unchanged. The lowest level of detection (LLOD) for b-BSA bioassays were: 10M for 10nm STFs on PMMA and Ag NWs on paper and 10M for ITO. Bioassays for Ki-67 antigen yielded a LLOD of <10M on ITO platforms, while STFs platforms were deemed unusable due to significant loss of STFs from the surfaces.
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http://dx.doi.org/10.1016/j.colsurfb.2017.03.030DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5479633PMC
June 2017

Effect of Microwave Heating on the Crystallization of Glutathione Tripeptide on Silver Nanoparticle Films.

J Phys Chem C Nanomater Interfaces 2017 Mar 21;121(10):5585-5593. Epub 2017 Feb 21.

Morgan State University, Department of Chemistry, 1700 East Cold Spring Lane, Baltimore, Maryland 21251, United States.

Effect of microwave heating on the crystallization of glutathione (GSH) tripeptide using the metal-assisted and microwave-accelerated evaporative crystallization (MA-MAEC) technique is reported. GSH crystals were grown from supersaturated solutions of GSH (300-500 mg/mL) on the iCrystal plates with silver nanoparticle films (SNFs) and without SNFs in three different microwave systems operating at 2.45 GHz: conventional (multimode, fixed power at 900W), industrial (monomode, variable power up to 1200 W), and the iCrystal system (monomode, variable power up to 100 W). The efficacy of the MA-MAEC technique, in terms of improvement in the crystallization time, crystal size and quality of GSH, was compared between the three microwave systems and the crystallization at room temperature (no microwave heating, a control experiment). Optical microscopy was used to visualize and quantify the growth of GSH crystals during and after microwave heating. Powder X-ray diffraction (XRD) and Fourier transform infrared (FTIR) spectroscopy data showed that GSH crystals had identical crystal structure to those grown at room temperature and microwave heating did not alter the chemical structure of GSH molecules during microwave heating, respectively. Using the MA-MAEC technique, the iCrystal system yielded high quality GSH crystals in a rapid manner.
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http://dx.doi.org/10.1021/acs.jpcc.6b11952DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6508885PMC
March 2017

Ultra-Rapid Crystallization of L-alanine Using Monomode Microwaves, Indium Tin Oxide and Metal-Assisted and Microwave-Accelerated Evaporative Crystallization.

Nano Biomed Eng 2017 27;9(2):112-123. Epub 2017 May 27.

Department of Chemistry, Morgan State University, 1700 East Cold Spring Lane, Baltimore, MD 21209, USA.

The use of indium tin oxide (ITO) and focused monomode microwave heating for the ultra-rapid crystallization of L-alanine (a model amino acid) is reported. Commercially available ITO dots (< 5 mm) attached to blank poly(methyl)methacrylate (PMMA, 5 cm in diameter with 21-well silicon isolators: referred to as the iCrystal plates) were found to withstand prolonged microwave heating during crystallization experiments. Crystallization of L-alanine was performed at room temperature (a control experiment), with the use of two microwave sources: a 2.45 GHz conventional microwave (900 W, power level 1, a control experiment) and 8 GHz (20 W) solid state, monomode microwave source with an applicator tip that focuses the microwave field to a 5-mm cavity. Initial appearance of L-alanine crystals and on iCrystal plates with ITO dots took 47 ± 2.9 min, 12 ± 7.6 min and 1.5 ± 0.5 min at room temperature, using a conventional microwave and focused monomode microwave heating, respectively. Complete evaporation of the solvent using the focused microwaves was achieved in 3.2 ± 0.5 min, which is ~52-fold and ~172-fold faster than that observed at room temperature and using conventional microwave heating, respectively. The size and number of L-alanine crystals was dependent on the type of the 21-well iCrystal plates and the microwave heating method: 33 crystals of 585 ± 137 μm in size at room temperature > 37 crystals of 542 ± 100 μm in size with conventional microwave heating > 331 crystals of 311 ± 190 μm in size with focused monomode microwave. FTIR, optical microscopy and powder X-ray diffraction analysis showed that the chemical composition and crystallinity of the L-alanine crystals did not change when exposed to microwave heating and ITO surfaces. In addition, theoretical simulations for the binding of L-alanine molecules to ITO and other metals showed the predicted nature of hydrogen bonds formed between L-alanine and these surfaces.
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http://dx.doi.org/10.5101/nbe.v9i2.p112-123DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5897105PMC
May 2017

Microwave Heating of Synthetic Skin Samples for Potential Treatment of Gout Using the Metal-Assisted and Microwave-Accelerated Decrystallization Technique.

ACS Omega 2016 Nov 1;1(5):744-754. Epub 2016 Nov 1.

Department of Chemistry and Department of Physics and Engineering Physics, Morgan State University , 1700 East Cold Spring Lane, Baltimore, Maryland 21251, United States.

Physical stability of synthetic skin samples during their exposure to microwave heating was investigated to demonstrate the use of the metal-assisted and microwave-accelerated decrystallization (MAMAD) technique for potential biomedical applications. In this regard, optical microscopy and temperature measurements were employed for the qualitative and quantitative assessment of damage to synthetic skin samples during 20 s intermittent microwave heating using a monomode microwave source (at 8 GHz, 2-20 W) up to 120 s. The extent of damage to synthetic skin samples, assessed by the change in the surface area of skin samples, was negligible for microwave power of ≤7 W and more extensive damage (>50%) to skin samples occurred when exposed to >7 W at initial temperature range of 20-39 °C. The initial temperature of synthetic skin samples significantly affected the extent of change in temperature of synthetic skin samples during their exposure to microwave heating. The proof of principle use of the MAMAD technique was demonstrated for the decrystallization of a model biological crystal (l-alanine) placed under synthetic skin samples in the presence of gold nanoparticles. Our results showed that the size (initial size ∼850 μm) of l-alanine crystals can be reduced up to 60% in 120 s without damage to synthetic skin samples using the MAMAD technique. Finite-difference time-domain-based simulations of the electric field distribution of an 8 GHz monomode microwave radiation showed that synthetic skin samples are predicted to absorb ∼92.2% of the microwave radiation.
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http://dx.doi.org/10.1021/acsomega.6b00233DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5131323PMC
November 2016

Decrystallization of Crystals Using Gold "Nano-Bullets" and the Metal-Assisted and Microwave-Accelerated Decrystallization Technique.

Molecules 2016 Oct 18;21(10). Epub 2016 Oct 18.

Department of Chemistry, Morgan State University, 1700 East Cold Spring Lane, Baltimore, MD 21251, USA.

Gout is caused by the overproduction of uric acid and the inefficient metabolism of dietary purines in humans. Current treatments of gout, which include anti-inflammatory drugs, cyclooxygenase-2 inhibitors, and systemic glucocorticoids, have harmful side-effects. Our research laboratory has recently introduced an innovative approach for the decrystallization of biological and chemical crystals using the Metal-Assisted and Microwave-Accelerated Evaporative Decrystallization (MAMAD) technique. In the MAMAD technique, microwave energy is used to heat and activate gold nanoparticles that behave as "nano-bullets" to rapidly disrupt the crystal structure of biological crystals placed on planar surfaces. In this study, crystals of various sizes and compositions were studied as models for tophaceous gout at different stages (i.e., uric acid as small crystals (~10-100 μm) and l-alanine as medium (~300 μm) and large crystals (~4400 μm). Our results showed that the use of the MAMAD technique resulted in the reduction of the size and number of uric acid and l-alanine crystals up to >40% when exposed to intermittent microwave heating (up to 20 W power at 8 GHz) in the presence of 20 nm gold nanoparticles up to 120 s. This study demonstrates that the MAMAD technique can be potentially used as an alternative therapeutic method for the treatment of gout by effective decrystallization of large crystals, similar in size to those that often occur in gout.
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http://dx.doi.org/10.3390/molecules21101388DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5409504PMC
October 2016

Synthesis, characterization, and evaluation of (E)-methyl 2-((2-oxonaphthalen-1(2H)-ylidene)methylamino)acetate as a biological agent and an anion sensor.

Bioorg Med Chem 2016 11 13;24(21):5592-5601. Epub 2016 Sep 13.

Morgan State University, Department of Chemistry, 1700 East Cold Spring Lane, Baltimore, MD 21251, USA. Electronic address:

An amino acid based and bidentate Schiff base, (E)-methyl 2-((2-oxonaphthalen-1(2H)-ylidene)methylamino)acetate (ligand), was synthesized from the reaction of glycine-methyl ester hydrochloride with 2-hydroxy-1-naphthaldehyde. Characterization of the ligand was carried out using theoretical quantum-mechanical calculations and experimental spectroscopic methods. The molecular structure of the compound was confirmed using X-ray single-crystal data, NMR, FTIR and UV-Visible spectroscopy, which were in good agreement with the structure predicted by the theoretical calculations using density functional theory (DFT). Antimicrobial activity of the ligand was investigated for its minimum inhibitory concentration (MIC) to several bacteria and yeast cultures. UV-Visible spectroscopy studies also shown that the ligand can bind calf thymus DNA (CT-DNA) electrostatic binding. In addition, DNA cleavage study showed that the ligand cleaved DNA without the need for external agents. Energetically most favorable docked structures were obtained from the rigid molecular docking of the compound with DNA. The compound binds at the active site of the DNA proteins by weak non-covalent interactions. The colorimetric response of the ligand in DMSO to the addition of equivalent amount of anions (F, Br, I, CN, SCN, ClO, HSO, AcO, HPO, N and OH) was investigated and the ligand was shown to be sensitive to CN anion.
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http://dx.doi.org/10.1016/j.bmc.2016.09.018DOI Listing
November 2016

A Highly Selective Sensor for Cyanide in Organic Media and on Solid Surfaces.

Sensors (Basel) 2016 Feb 24;16(3):271. Epub 2016 Feb 24.

Department of Chemistry, Morgan State University, Baltimore, MD 21251, USA.

The application of IR 786 perchlorate (IR-786) as a selective optical sensor for cyanide anion in both organic solution (acetonitrile (MeCN), 100%) and solvent-free solid surfaces was demonstrated. In MeCN, IR-786 was selective to two anions in the following order: CN(-) > OH(-). A significant change in the characteristic dark green color of IR-786 in MeCN to yellow was observed as a result of nucleophilic addition of CN(-) to the fluorophore, i.e., formation of IR 786-(CN), which was also verified by a blue shift in the 775 nm absorbance peak to 430 nm. A distinct green fluorescence emission from the IR-786-(CN) in MeCN was also observed, which demonstrated the selectivity of IR-786 towards CN(-) in MeCN. Fluorescence emission studies of IR-786 showed that the lower detection limit and the sensitivity of IR-786 for CN(-) in MeCN was 0.5 μM and 0.5 to 8 μM, respectively. The potential use of IR-786 as a solvent-free solid state sensor for the selective sensing and monitoring of CN(-) in the environment was also demonstrated. On solvent-free solid state surfaces, the sensitivity of the IR-786 to CN(-) in water samples was in the range of 50-300 μM with minimal interference by OH(-).
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http://dx.doi.org/10.3390/s16030271DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4813846PMC
February 2016

Enhancement of the Chemiluminescence Response of Enzymatic Reactions by Plasmonic Surfaces for Biosensing Applications.

Nano Biomed Eng 2015;7(3):92-101. Epub 2015 Sep 15.

Morgan State University, Department of Chemistry, 1700 East Cold Spring Lane, Baltimore, MD 21251 USA.

We report the enhancement of chemiluminescence response of horseradish peroxidase (HRP) in bioassays by plasmonic surfaces, which are comprised of (i) silver island films (SIFs) and (ii) metal thin films (silver, gold, copper, and nickel, 1 nm thick) deposited onto glass slides. A model bioassay, based on the interactions of avidin-modified HRP with a monolayer of biotinylated poly(ethylene-glycol)-amine, was employed to evaluate the ability of plasmonic surfaces to enhance chemiluminescence response of HRP. Chemiluminescence response of HRP in model bioassays were increased up to ~3.7-fold as compared to the control samples (i.e. glass slides without plasmonic nanoparticles), where the largest enhancement of the chemiluminescence response was observed on SIFs with high loading. These findings allowed us to demonstrate the use of SIFs (high loading) for the detection of a biologically relevant target protein (glial fibrillary acidic protein or GFAP), where the chemiluminescence response of the standard bioassay for GFAP was enhanced up to ~50% as compared to bioassay on glass slides.
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http://dx.doi.org/10.5101/nbe.v7i3.p92-101.DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4646423PMC
September 2015

Microwave-accelerated bioassay technique for rapid and quantitative detection of biological and environmental samples.

Biosens Bioelectron 2016 Jan 31;75:420-6. Epub 2015 Aug 31.

Morgan State University, Department of Chemistry, 1700 East Cold Spring Lane, Baltimore, MD 21251, United States. Electronic address:

Quantitative detection of molecules of interest from biological and environmental samples in a rapid manner, particularly with a relevant concentration range, is imperative to the timely assessment of human diseases and environmental issues. In this work, we employed the microwave-accelerated bioassay (MAB) technique, which is based on the combined use of circular bioassay platforms and microwave heating, for rapid and quantitative detection of Glial Fibrillary Acidic Protein (GFAP) and Shiga like toxin (STX 1). The proof-of-principle use of the MAB technique with the circular bioassay platforms for the rapid detection of GFAP in buffer based on colorimetric and fluorescence readouts was demonstrated with a 900W kitchen microwave. We also employed the MAB technique with a new microwave system (called the iCrystal system) for the detection of GFAP from mice with brain injuries and STX 1 from a city water stream. Control bioassays included the commercially available gold standard bioassay kits run at room temperature. Our results show that the lower limit of detection (LLOD) of the colorimetric and fluorescence based bioassays for GFAP was decreased by ~1000 times using the MAB technique and our circular bioassay platforms as compared to the commercially available bioassay kits. The overall bioassay time for GFAP and STX 1 was reduced from 4h using commercially available bioassay kits to 10min using the MAB technique.
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http://dx.doi.org/10.1016/j.bios.2015.08.061DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4583200PMC
January 2016

Enhancement of Colorimetric Response of Enzymatic Reactions by Thermally Evaporated Plasmonic Thin Films: Application to Glial Fibrillary Acidic Protein.

Anal Methods 2015 Feb;7(3):1175-1185

Morgan State University, Department of Chemistry, 1700 East Cold Spring Lane, Baltimore, MD 21251 USA.

We report the enhancement of the colorimetric response of horseradish peroxidase (HRP) and alkaline phosphatase (AP) in bioassays by thermally evaporated silver, gold, copper and nickel thin films. In this regard, a model bioassay based on biotin-avidin interactions was employed. Biotin groups and enzymes were introduced to all surfaces using a biotinylated linker molecule and avidin, respectively. The colorimetric response of HRP in the model bioassay carried out on the plasmonic thin films were up to 4.4-fold larger as compared to control samples (i.e., no plasmonic thin films), where the largest enhancement of colorimetric response was observed on silver thin films. The colorimetric response of AP on plasmonic thin films was found to be similar to those observed on control samples, which was attributed to the loss of enzymes from the surface during the bioassay steps. The extent of enzymes immobilized on to plasmonic thin films was found to affect the colorimetric response of the model bioassay. These findings allowed us to demonstrate the use of silver thin films for the detection of glial fibrillary acidic protein (GFAP), where the colorimetric response of the standard bioassays for GFAP was enhanced up to 67% as compared to bioassays on glass slides.
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http://dx.doi.org/10.1039/C4AY02505ADOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4318255PMC
February 2015

Metal-Enhanced Fluorescence from Silver Nanowires with High Aspect Ratio on Glass Slides for Biosensing Applications.

J Phys Chem C Nanomater Interfaces 2015 Jan 10;119(1):675-684. Epub 2014 Dec 10.

Department of Chemistry, Morgan State University , 1700 East Cold Spring Lane, Baltimore, Maryland 21251, United States.

High enhancement of fluorescence emission, improved fluorophore photostability, and significant reduction of fluorescence lifetimes have been obtained from high aspect ratio (>100) silver (Ag) nanowires. These quantities are found to depend on the surface loading of Ag nanowires on glass slides, where the enhancement of fluorescence emission increases with the density of nanowires. The surface loading dependence was attributed to the creation of intense electric fields around the network of Ag nanowires and to the coupling of fluorophore excited states that takes place efficiently at a distance of 10 nm from the surface of nanowires, which was confirmed by theoretical calculations. The enhancement of fluorescence emission of fluorescein isothiocyanate (FITC) was assessed by fluorescence spectroscopy and fluorescence-lifetime imaging microscopy (FLIM) to demonstrate the potential of high aspect ratio Ag nanowires. Fluorescence enhancement factors exceeding 14 were observed on Ag nanowires with high loading by FLIM. The photostability of FITC was the highest on nanowires with medium loading under continuous laser excitation for 10 min because of the significant reduction in the fluorescence lifetime of FITC on these surfaces. These results clearly demonstrate the potential of Ag nanowires in metal-enhanced fluorescence-based applications of biosensing on planar surfaces and cellular imaging.
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http://dx.doi.org/10.1021/jp509040fDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4291037PMC
January 2015

Circular Bioassay Platforms for Applications in Microwave-Accelerated Techniques.

Nano Biomed Eng 2014 Dec;6(4):85-93

Morgan State University, Department of Chemistry, Baltimore MD 21251.

In this paper, we present the design of four different circular bioassay platforms, which are suitable for homogeneous microwave heating, using theoretical calculations (i.e., COMSOL™ multiphysics software). Circular bioassay platforms are constructed from poly(methyl methacrylate) (PMMA) for optical transparency between 400-800 nm, has multiple sample capacity (12, 16, 19 and 21 wells) and modified with silver nanoparticle films (SNFs) to be used in microwave-accelerated bioassays (MABs). In addition, a small monomode microwave cavity, which can be operated with an external microwave generator (100 W), for use with the bioassay platforms in MABs is also developed. Our design parameters for the circular bioassay platforms and monomode microwave cavity during microwave heating were: (i) temperature profiles, (ii) electric field distributions, (iii) location of the circular bioassay platforms inside the microwave cavity, and (iv) design and number of wells on the circular bioassay platforms. We have also carried out additional simulations to assess the use of circular bioassay platforms in a conventional kitchen microwave oven (e.g., 900 W). Our results show that the location of the circular bioassay platforms in the microwave cavity was predicted to have a significant effect on the homogeneous heating of these platforms. The 21-well circular bioassay platform design in our monomode microwave cavity was predicted to offer a homogeneous heating pattern, where inter-well temperature was observed to be in between 23.72-24.13°C and intra-well temperature difference was less than 0.21°C for 60 seconds of microwave heating, which was also verified experimentally.
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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4283778PMC
http://dx.doi.org/10.5101/nbe.v6i4.p85-93DOI Listing
December 2014

Rapid and Sensitive Detection of p53 Based on DNA-Protein Binding Interactions Using Silver Nanoparticle Films and Microwave Heating.

Nano Biomed Eng 2014 Nov;6(3):76-84

Morgan State University, Department of Chemistry, 1700 East Cold Spring Lane, Baltimore MD 21251.

Tumor detection can be carried out via the detection of proteins, such as p53, which is known to play vital role in more than 50% of all cancers affecting humans. Early diagnosis of tumor detection can be achieved by decreasing the lower detection limit of p53 bioassays. Microwave-accelerated bioassay (MAB) technique, which is based on the use of circular bioassay platforms in combination with microwave heating, is employed for the rapid and sensitive detection of p53 protein. Direct sandwich ELISA was constructed on our circular bioassay platforms based on DNA-protein binding interactions. Colorimetric and fluorescence based detection methods were used for room temperature bioassay (control bioassay; total bioassay time is 27 hours) and bioassay using microwave heating (i.e., the MAB technique; total bioassay time is 10 minutes). In the colorimetric based detection, a very high background signal due to the non-specific binding of proteins for the bioassay carried out at room temperature and a LLOD of 0.01 ng/mL for p53 was observed using the MAB technique. The LLOD for the fluorescence-based detection using the MAB technique was found to be 0.01 ng/mL. The use of circular bioassay platforms in the MAB technique results in microwave-induced temperature gradient, where the specific protein binding interactions are significantly accelerated; thereby reducing the background signal and the lower limit of detection of p53 protein.
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http://dx.doi.org/10.5101/nbe.v6i3.p76-84DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4283572PMC
November 2014

Enhancement of enzymatic colorimetric response by silver island films on high throughput screening microplates.

J Immunol Methods 2014 Sep 17;411:43-9. Epub 2014 Jun 17.

Morgan State University, Department of Chemistry, 1700 East Cold Spring Lane, Baltimore, MD 21251, USA. Electronic address:

In this study, we report the use of an enzyme-based hybrid platform, which is comprised of silver island films, enzymes (HRP and AP) and high-throughput screening (HTS) microplates, to enhance the colorimetric response of enzymatic reactions. The hybrid platform was designed in a two-step process: (i) deposition of SIFs onto HTS microplates with low, medium, and high loading (refers to the extent of the surface plasmon resonance peak of SIFs at 460 nm) using Tollen's reaction scheme; and (ii) attachment of b-BSA or BEA as linkers for the immobilization of enzymes. The presence of SIFs within the wells of the HTS microplates was confirmed using an optical spectrophotometer and real-color photography. Control experiments, where SIFs were omitted from the surfaces were carried out to confirm the effect of SIFs on the enzymatic colorimetric response. Significant colorimetric signal enhancement was observed for HRP or AP on SIFs (high loading) deposited HTS microplates using b-BSA (up to ~3-fold for AP and ~6-fold HRP) or BEA (up to ~7-fold for both HRP and AP), as compared to our control samples. The observed increase in colorimetric response can be attributed to the nature of BEA, which exposes surface-bound enzymes to the substrate present in bulk more efficiently than b-BSA. This study proves that SIFs can serve as a valuable tool to improve the signal output of existing bioassays carried out in HTS microplates, which can be applicable to the field biosensors and plasmonics.
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http://dx.doi.org/10.1016/j.jim.2014.06.005DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4171191PMC
September 2014

Crystal Engineering of l-Alanine with l-Leucine Additive using Metal-Assisted and Microwave-Accelerated Evaporative Crystallization.

Cryst Growth Des 2014 May 21;14(5):2494-2501. Epub 2014 Mar 21.

Department of Chemistry, Morgan State University , 1700 East Cold Spring Lane, Baltimore, Maryland 21251 United States.

In this work, we demonstrated that the change in the morphology of l-alanine crystals can be controlled with the addition of l-leucine using the metal-assisted and microwave accelerated evaporative crystallization (MA-MAEC) technique. Crystallization experiments, where an increasing stoichiometric amount of l-leucine is added to initial l-alanine solutions, were carried out on circular poly(methyl methacrylate) (PMMA) disks modified with a 21-well capacity silicon isolator and silver nanoparticle films using microwave heating (MA-MAEC) and at room temperature (control experiments). The use of the MA-MAEC technique afforded for the growth of l-alanine crystals with different morphologies up to ∼10-fold faster than those grown at room temperature. In addition, the length of l-alanine crystals was systematically increased from ∼380 to ∼2000 μm using the MA-MAEC technique. Optical microscope images revealed that the shape of l-alanine crystals was changed from tetragonal shape (without l-leucine additive) to more elongated and wire-like structures with the addition of the l-leucine additive. Further characterization of l-alanine crystals was undertaken by Fourier transform infrared (FT-IR) spectroscopy, Raman spectroscopy and powder X-ray diffraction (PXRD) measurements. In order to elucidate the growth mechanism of l-alanine crystals, theoretical simulations of l-alanine's morphology with and without l-leucine additive were carried out using Materials Studio software in conjunction with our experimental data. Theoretical simulations revealed that the growth of l-alanine's {011} and {120} crystal faces were inhibited due to the incorporation of l-leucine into these crystal faces in selected positions.
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http://dx.doi.org/10.1021/cg500204tDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4018178PMC
May 2014

De-crystallization of Uric Acid Crystals in Synovial Fluid Using Gold Colloids and Microwave Heating.

Nano Biomed Eng 2014;6(4):104-110

Morgan State University, Department of Chemistry, 1700 East Cold Spring Lane.

In this study, we demonstrated a unique application of our Metal-Assisted and Microwave-Accelerated Evaporative Crystallization (MA-MAEC) technique for the de-crystallization of uric acid crystals, which causes gout in humans when monosodium urate crystals accumulate in the synovial fluid found in the joints of bones. Given the shortcomings of the existing treatments for gout, we investigated whether the MA-MAEC technique can offer an alternative solution to the treatment of gout. Our technique is based on the use of metal nanoparticles (i.e., gold colloids) with low microwave heating to accelerate the de-crystallization process. In this regard, we employed a two-step process; (i) crystallization of uric acid on glass slides, which act as a solid platform to mimic a bone, (ii) de-crystallization of uric acid crystals on glass slides with the addition of gold colloids and low power microwave heating, which act as "nano-bullets" when microwave heated in a solution. We observed that the size and number of the uric acid crystals were reduced by >60% within 10 minutes of low power microwave heating. In addition, the use of gold colloids without microwave heating (i.e. control experiment) did not result in the de-crystallization of the uric acid crystals, which proves the utility of our MA-MAEC technique in the de-crystallization of uric acid.
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http://dx.doi.org/10.5101/nbe.v6i4.p104-110DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4346785PMC
January 2014

Design and Proof-of-Concept Use of a Circular PMMA Platform with 16-Well Sample Capacity for Microwave-Accelerated Bioassays.

Nano Biomed Eng 2013 Jan;5(1):10-19

Morgan State University, Department of Chemistry, Baltimore, Maryland 21251.

We demonstrate the design and the use of a new, circular poly(methyl methacrylate)-based bioassay platform (PMMA platform), which affords for the rapid processing of 16 samples at once. The circular PMMA platform (5 cm in diameter) was coated with a silver nanoparticle film to accelerate the bioassay steps by microwave heating. A model colorimetric bioassay for biotinylated albumin (using streptavidin-labeled horse radish peroxidase) was performed on the PMMA platform coated with and without silver nanoparticles (a control experiment), and at room temperature and using microwave heating. It was shown that the simulated temperature profile of the PMMA platform during microwave heating were comparable to the real-time temperature profile during actual microwave heating of the constructed PMMA platform in a commercial microwave oven. The model colorimetric bioassay for biotinylated albumin was successfully completed in ~2 min (total assay time) using microwave heating, as compared to 90 min at room temperature (total assay time), which indicates a ~45-fold decrease in assay time. Our PMMA platform design afforded for significant reduction in non-specific interactions and low background signal as compared to non-silvered PMMA surfaces when employed in a microwave-accelerated bioassay carried out in a conventional microwave cavity.
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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3838103PMC
http://dx.doi.org/10.5101/nbe.v5i1.p20-27DOI Listing
January 2013

Immobilization of enzymes to silver island films for enhanced enzymatic activity.

J Colloid Interface Sci 2014 Feb 24;415:133-42. Epub 2013 Oct 24.

Morgan State University, Department of Chemistry, 1700 East Cold Spring Lane, Baltimore, MD 21251, USA.

Hypothesis: The performance of the enzyme-based biosensors depends on the enzymatic activity and the use of an appropriate technique for immobilization of enzymes. The incorporation of silver island films (SIFs) into the enzyme-based biosensors is expected to enhance the enzymatic activity and to increase the detectability of analytes of interest.

Experiments: Two enzymes, β-galactosidase (β-Gal) and alkaline phosphatase (AP) were immobilized onto SIFs using the interactions of avidin-modified enzymes with (i) a monolayer of biotinylated bovine serum albumin (b-BSA) and/or (ii) a monolayer of biotinylated poly(ethylene-glycol)-amine (BEA molecular weight: 550-10,000Da). To confirm the effect of SIFs on enzymatic activity, two control surfaces (no silver) were also employed.

Findings: No enhancement in enzymatic activity for β-Gal on all SIFs was observed, which was attributed to the inhibition of β-Gal activity due to direct interactions of β-Gal with SIFs. The AP activity on SIFs with BEA was significantly larger than that observed on SIFs with b-BSA, where a 300% increase in AP activity was observed as compared to control surfaces. These observations suggest that SIFs can significantly enhance AP activity, which could help improve the detection limits of ELISAs and immunoassays that employ AP.
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http://dx.doi.org/10.1016/j.jcis.2013.10.026DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3863589PMC
February 2014

Microwave-accelerated surface modification of plasmonic gold thin films with self-assembled monolayers of alkanethiols.

Langmuir 2013 Oct 18;29(43):13209-16. Epub 2013 Oct 18.

Department of Chemistry, Morgan State University , 1700 East Cold Spring Lane, Baltimore, Maryland 21251, United States.

A rapid surface modification technique for the formation of self-assembled monolayers (SAMs) of alkanethiols on gold thin films using microwave heating in <10 min is reported. In this regard, SAMs of two model alkanethiols, 11-mercaptoundecanoic acid (11-MUDA, to generate a hydrophilic surface) and undecanethiol (UDET, a hydrophobic surface), were successfully formed on gold thin films using selective microwave heating in (1) a semicontinuous fashion and (2) a continuous fashion at room temperature (24 h, control experiment, no microwave heating). The formation of SAMs of 11-MUDA and UDET was confirmed by contact angle measurements, Fourier transform infrared (FT-IR) spectroscopy, and X-ray photoelectron spectroscopy (XPS). The contact angles for water on SAMs formed by the selective microwave heating and conventional room temperature incubation technique (24 h) were measured to be similar for 11-MUDA and UDET. FT-IR spectroscopy results confirmed that the internal structures of SAMs prepared using both microwave heating and room temperature were similar. XPS results revealed that the organic and sulfate contaminants found on bare gold thin films were replaced by SAMs after the surface modification process had been conducted using both microwave heating and room temperature.
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http://dx.doi.org/10.1021/la402455xDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3863588PMC
October 2013

Surface modification of plasmonic nanostructured materials with thiolated oligonucleotides in 10 seconds using selective microwave heating.

Ann Phys 2012 Nov;524(11):741-750

Morgan State University, Department of Chemistry, 1700 East Cold Spring Lane, Baltimore, MD 21251 USA.

This study demonstrates the proof-of-principle of rapid surface modification of plasmonic nanostructured materials with oligonucleotides using low power microwave heating. Due to their interesting optical and electronic properties, silver nanoparticle films (SNFs, 2 nm thick) deposited onto glass slides were used as the model plasmonic nanostructured materials. Rapid surface modification of SNFs with oligonucleotides was carried out using two strategies (1) Strategy 1: for ss-oligonucleotides, surface hybridization and (2) Strategy 2: for ds-oligonucleotides, solution hybridization), where the samples were exposed to 10, 15, 30 and 60 seconds microwave heating. To assess the efficacy of our new rapid surface modification technique, identical experiments carried out without the microwave heating (i.e., conventional method), which requires 24 hours for the completion of the identical steps. It was found that SNFs can be modified with ss- and ds-oligonucleotides in 10 seconds, which typically requires several hours of incubation time for the chemisorption of thiol groups on to the planar metal surface using conventional techniques.
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http://dx.doi.org/10.1002/andp.201200125DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3640794PMC
November 2012

Crystallization of l-alanine in the presence of additives on a circular PMMA platform designed for metal-assisted and microwave-accelerated evaporative crystallization.

CrystEngComm 2012 Dec;14(24):8424-8431

The College of New Jersey, Department of Chemistry, 2000 Pennington Road, Ewing, NJ, 08628, USA.

Crystallization of l-alanine in the presence of l-valine and l-tryptophan additives on a circular poly(methyl) methacrylate (PMMA) platform designed for Metal-Assisted and Microwave-Accelerated Evaporative Crystallization (MA-MAEC) technique was investigated. Theoretical simulations predicted homogeneous temperature and electric field distributions across the circular PMMA platforms during microwave heating. Crystallization of l-alanine with and without additives on the blank and silver nanoparticle films (SNFs) modified sides of the circular PMMA platform occurred within 32-50 min using MA-MAEC technique, while the identical solutions crystallized within 161-194 min at room temperature. Optical microscopy studies revealed that l-alanine crystals without additives were found to be smaller in size and had several well-developed faces, whereas l-alanine crystals grown with additives appeared to be larger and had only one dominant highly-developed face. Raman spectroscopy and powder X-ray diffraction (XRD) measurements showed that all l-alanine crystals had identical peaks, despite the morphological differences between the l-alanine crystals with and without additives observed by optical microscope images.
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http://dx.doi.org/10.1039/C2CE26363GDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3560919PMC
December 2012

Rapid crystallization of glycine using metal-assisted and microwave-accelerated evaporative crystallization: the effect of engineered surfaces and sample volume.

Nano Biomed Eng 2012 ;4(3):125-131

Morgan State University, Department of Chemistry, 1700 East Cold Spring Lane, Baltimore, MD 21251, USA.

Metal-Assisted and Microwave-Accelerated Evaporative Crystallization (MA-MAEC), is a new approach to crystallization of drug compounds, amino acids, DNA and proteins. In this work, we report our additional findings on the effect of engineered surfaces and sample volume on the rapid crystallization of glycine. With the use of hydrophilic functionalized surfaces and the MA-MAEC technique, glycine crystals ~1 mm in size were grown in 35 seconds with 100% selectivity for the α-form.The use of moderately hydrophobic surfaces resulted in the growth of glycine crystals only at room temperature. An increase in volume of initial glycine solution (5-100 μL) resulted in an increase in crystal size without a significant increase in total crystallization time. Raman spectroscopy and powder X-ray diffraction results demonstrated that the glycine crystals grown on engineered surfaces were structurally identical to those grown using conventional evaporative crystallization.
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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3548239PMC
http://dx.doi.org/10.5101/nbe.v4i3.p125-131DOI Listing
January 2012