High-Throughput Crystallization of l-Alanine Using iCrystal Plates and Metal-Assisted and Microwave-Accelerated Evaporative Crystallization

Abstract

We present a comprehensive study of highthroughput crystallization of L-alanine (a model amino acid) using circular crystallization platforms (are hereafter referred to as the iCrystal plates) designed to work with the metalassisted and microwave-accelerated evaporative crystallization (MA-MAEC) technique. The iCrystal plates are constructed using a circular 21-, 95-, and 204-well design that afford for homogeneous microwave heating of all samples. In addition, the iCrystal plates were modified with metal thin films (gold, copper, silver, and nickel), which act as selective nucleation sites for selective crystallization to occur on the surface of the crystallization platforms. Silver thin films were found to be ideal for MA-MAEC applications as compared to other metal surfaces based on the observations of crystal number and size. The size and number of wells on the iCrystal plates were found to have negligible effect on the growth of L-alanine crystals, where all three iCrystal plates were found to have similar crystallization times and yield identical crystal quality. These results imply that one can employ the iCrystal plates for the crystallization of a small number of samples (with 21-well capacity) and a large number of samples (95-and 204-well capacity) with identical yields using the MA-MAEC technique.

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

“…In this regard, ITO films, which are developed for solar energy technology, are proven successful in all the criteria mentioned above. The Aslan Research Group have previously demonstrated the use of silver, gold, nickel and copper for rapid crystallization of amino acids in a recent publication [ 23 ].…”

Metal-assisted and microwave-accelerated evaporative crystallization: an approach to rapid crystallization of biomolecules

“…5). 9 The longest crystallization time (i.e., when the complete evaporation of the solvent occurred) was observed on nickel-coated platforms with a time of ∼275 min at room temperature (Fig. 5).…”

“…The use of iCrystal plates with silver thin films at 50 °C along with microwave heating resulted in the growth of the largest number of L-alanine crystals (∼154 in 21-wells) and ranging in size between 59-625 μm as compared to all other experimental conditions. 9 The observed differences in the complete solvent evaporation time can be attributed to the differences in the thermal conductivities of the metal surfaces, which results in different rates of cooling of L-alanine solution.…”

“…6 Crystallization of proteins are mainly controlled by kinetic and thermodynamic factors, and therefore, high-throughput crystallization methods are necessary for rapid drug development in today's world. [7][8][9] Aforementioned are the reasons for engag-ing in protein structure studies 40 years after deciphering the background of inorganic crystal structures by Bragg. 10,11 Crystallization Crystallization is a phase transition phenomenon.…”

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

“…The crux of the MA-MAEC technique is the generation of microwave-induced thermal gradients and the subsequent rapid mass transfer of biomolecules directed toward the metal nanostructures on planar surfaces that act as nucleation sites and microwave-transparent medium. Metal nanostructures of silver, gold, copper, nickel, and indium tin oxide are deposited onto poly­(methyl methacrylate) (PMMA) platforms combined with silicon isolators (i.e., the iCrystal plates). − The unique design of the iCrystal plates ensures that microwave radiation is distributed homogeneously across the wells formed by the silicon isolator. , In studies based on the MA-MAEC technique by our research group to date, two different microwave systems operating at 2.45 GHz was employed: a multimode conventional microwave system (fixed power, 700–1000 W) , and the iCrystal system (monomode, variable power up to 100 W) . Conventional microwave system is a commercially available microwave oven that was initially used to demonstrate the proof-of-principle demonstration and applications of the MA-MAEC technique for the crystallization of biological compounds. − The iCrystal microwave system is an instrument developed by our research group and was also employed for the crystallization of a variety of biomolecules …”