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 hu...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.展开更多
Effect of intermittent monomode microwave heating on the crystallization of glutathione(GSH)and lysozyme on indium tin oxide(ITO)films using the metal-assisted and microwave-accelerated evaporative crystallization(MA-...Effect of intermittent monomode microwave heating on the crystallization of glutathione(GSH)and lysozyme on indium tin oxide(ITO)films using the metal-assisted and microwave-accelerated evaporative crystallization(MA-MAEC)technique was investigated.Intermittent time intervals of 5,10,15,30,40,60,120,180,240 min and 30,40,60,120,180,240 min were employed for microwave heating of solutions of GSH(500 mg/mL)and lysozyme(40 mg/mL)using a monomode microwave source at 70 W,respectively.Optical microscopy and ImageJ software were employed to quantify and compare the size and number of GSH and lysozyme crystals grown at different microwave heating time intervals.The rate of crystallization for GSH crystals was found to be the fastest at~7.52μm/min for the 5 min interval of microwave heating and decreased to 0.57μm/min as the time interval of microwave heating was increased to 240 min.The rate of crystallization for lysozyme crystals was found to be 0.20~0.27μm/min for 30-120 min of microwave heating and decreased to 0.07μm/min as the time interval of microwave heating was increased to 240 min.Intermittent microwave heating of GSH and lysozyme solutions were found to have a minimal influence on the size and count of the crystals produced.X-ray crystallography studies and Fourier transform infrared(FTIR)spectroscopic analysis of grown crystals confirmed that the duration of microwave heating have no or little effect on the crystal morphology and molecular structure of biomolecules studied.展开更多
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(me...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±137μm in size at room temperature>37 crystals of 542±100μm in size with conventional microwave heating>331 crystals of 311±190μm 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.展开更多
基金supported(to B.Kioko)by National Institutes of Health(MBRS RISE)award number 5-R25GM058904-14.
文摘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.
文摘Effect of intermittent monomode microwave heating on the crystallization of glutathione(GSH)and lysozyme on indium tin oxide(ITO)films using the metal-assisted and microwave-accelerated evaporative crystallization(MA-MAEC)technique was investigated.Intermittent time intervals of 5,10,15,30,40,60,120,180,240 min and 30,40,60,120,180,240 min were employed for microwave heating of solutions of GSH(500 mg/mL)and lysozyme(40 mg/mL)using a monomode microwave source at 70 W,respectively.Optical microscopy and ImageJ software were employed to quantify and compare the size and number of GSH and lysozyme crystals grown at different microwave heating time intervals.The rate of crystallization for GSH crystals was found to be the fastest at~7.52μm/min for the 5 min interval of microwave heating and decreased to 0.57μm/min as the time interval of microwave heating was increased to 240 min.The rate of crystallization for lysozyme crystals was found to be 0.20~0.27μm/min for 30-120 min of microwave heating and decreased to 0.07μm/min as the time interval of microwave heating was increased to 240 min.Intermittent microwave heating of GSH and lysozyme solutions were found to have a minimal influence on the size and count of the crystals produced.X-ray crystallography studies and Fourier transform infrared(FTIR)spectroscopic analysis of grown crystals confirmed that the duration of microwave heating have no or little effect on the crystal morphology and molecular structure of biomolecules studied.
文摘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±137μm in size at room temperature>37 crystals of 542±100μm in size with conventional microwave heating>331 crystals of 311±190μm 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.
