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

Abstract

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.

Effect of Intermittent Monomode Microwave Heating on the Crystallization of Glutathione and Lysozyme on Indium Tin Oxide Films

“…In response to the limitations of current methods of crystallization, the Aslan Research Group has previously presented a method, called the metalassisted and microwave-accelerated evaporative crystallization (MA-MAEC) technique, which promotes the rapid and high-throughput crystallization of amino acids (i.e., alanine, glycine, arginine) [15][16][17], peptides (i.e., glutathione) [18], and proteins (i.e., lysozyme) [8,14]. The MA-MAEC technique was proven to increase the growth rate of crystallization in a shortened period while producing crystals that allow for analysis through diffraction screens [14][15][16][17].…”

“…Previous experiments utilizing the MA-MAEC technique yield fully developed crystals with the use of a conventional microwave system (multi-mode, fixed power at 900 W), industrial microwave (monomode, variable power up to 1200 W), and the iCrystal system (mono-mode, variable power up to 100 W). However, to optimize the technique, a comparative analysis of the efficiency of available microwave technology revealed that the iCrystal system rapidly produced the largest high-quality crystals with uniform size distribution within the shortest period [18].…”