We present a platform technology, called Metal-Assisted and Microwave-Accelerated Decrystallization (MAMAD), which is based on the use of dispersion of gold colloids with low power microwave heating to decrystallize organic and biological crystals attached to surfaces. Uric acid crystals were chosen as model target crystals to be decrystallized using MAMAD technique. A two-step procedure was employed: 1) growth of uric acid crystals on a model surface (collagen films coated on to glass slides to simulate a human joint) at room temperature and 2) de-crystallization of uric acid crystals in synovial fluid (in vitro) using silver and gold colloids in conjunction with low power microwave heating. Using the MAMAD technique with gold colloids, the number of uric acid crystals was drastically reduced by 80% after 10 min, where the average size of the uric acid crystals was reduced from 125 μm to 50 μm. In control experiments and with silver colloids that aggregated from the solution, the size and number of uric crystals remained unchanged, indicating that the combined use of only metal colloids in solution and microwave heating is effective for the de-crystallization of uric acid crystals in biological media.

The effect of metal surfaces on the crystallization of lysozyme using the Metal-Assisted and Microwave-Accelerated Evaporative Crystallization (MA-MAEC) technique and a monomode microwave system is described. Our microwave system (is called the iCrystal system hereafter for brevity) is comprised of a 100 W variable power monomode microwave source, a monomode cavity, fiber optic temperature probes and digital cameras. Crystallization of lysozyme (a model protein) was conducted using the iCrystal system on four different types of circular crystallization plates with 21-well sample capacity (i.e., crystallization plates): (i) blank: a continuous surface without a metal, (ii) silver nanoparticle films (SNFs): a discontinuous metal film, (iii) iron nano-columns: a semicontinuous metal film, and (iv) indium tin oxide (ITO): a continuous metal film. Lysozyme crystals grown on all crystallization plates were characterized by X-ray crystallography and found to be X-ray diffraction quality. The use of iron nano-columns afforded for the growth of largest number of lysozyme crystals with a narrow size distribution. ITO-modified crystallization plates were deemed to be best of all the crystallization plates based on the observations that lysozyme crystals were grown at the shortest time (370 ± 36 minutes) with a narrow size distribution up to 460 m in size.

Our laboratory has recently introduced and demonstrated the use of the metal-assisted and microwaveaccelerated evaporative crystallization (MA-MAEC) technique for rapid crystallization of biomolecules (e.g., amino acids, peptides and proteins). The MA-MAEC technique utilizes metal nanoparticles (silver, gold, copper, nickel, iron oxide, indium tin oxide), which are deposited on to iCrystal plates or glass surfaces to serve as selective nucleation sites and microwave-transparent medium to generate microwave-induced temperature gradients. In this highlight article, we will chronicle the effectiveness of the MA-MAEC technique as a rapid, efficient and easy to use technique for crystallization of biomolecules in potential applications in the pharmaceutical industry.

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.

A methodology is developed to visually analyze and quantify macroscale and mesoscale impact damage on a single layer of S-2 glass/SC15 toughened epoxy plain weave composite. Specimens were clamped in a 203 mm diameter circular frame and impacted by a 5.5 mm (0.22 caliber) right circular cylindrical steel projectile at impact velocities ranging from 104 to 472 m/s. High-resolution images were obtained at the point of impact and up to the edge of the circular frame using an 80 MP camera. Three types of mesoscale damage were identified: (i) transverse tow cracks, (ii) tow–tow delamination, and (iii) 45° matrix cracks. A MATLAB program was developed to translate the image data into a digital damage map whereby the output of color intensity correlated with the quantity and type of material damage. Digital maps generated for select specimens revealed that characteristic damage patterns arise for woven fabric composites including a diamond pattern in matrix cracking and a cross pattern in tow–tow delamination. The greatest extent of matrix cracks and tow–tow delamination over any specimen was observed for the projectile impact with initial velocity of 174 m/s, which is very close to the calculated ballistic limit velocity of 175 m/s.