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

Abstract

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.

Metal-Assisted and Microwave-Accelerated Decrystallization

“…Recently, the Aslan Research Group presented the initial observations for the use of colloidal gold solution with microwave heating for the decrystallization of uric acid crystals placed on unmodified glass slides, where 60% reduction in number of uric acid crystals were reported [15]. We hypothesized that the microwave-induced temperature gradients, which is generated between the metal colloids (not heated by microwaves) and the rest of the sample media (heated by microwaves), play an important role in the decrystallization of uric acid crystals by gold colloids.…”

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

“…The microwaves applied as a therapeutic aid in the MAMAD technique help keep the particles in suspension. The Kinetic energy increase experienced by the particles shows an increased in the collision force induced by the heat generated by the application of microwaves [33]. This article will summarize the results of the MAMAD technique since our initial paper in 2014.…”

“…Figure 1 depicts the crux of the MAMAD technique, where: 1) Upon irradiation with microwave energy, the differences in thermal conductivity of the Au NPs, the target crystals and water molecules produces a thermal gradient, 2) Kinetic energy of the Au NPs increases thereby affording the displacement of the Au NPs at high velocities, 3) High speed nanoparticles act as 'nano bullets' when they collide with the surface of crystals NPs) on the UA crystals is explained in the section below [33].…”

“…The MAMAD technique is based on the combined use of Gold Nanoparticles (Au NPs) in solution and the application of low powered direct microwave heating (e.g., 2.45-8 GHz) used for the rapid crystallization and decrystallization of various organic molecules [33,34]. Figure 1 depicts the crux of the MAMAD technique, where: 1) Upon irradiation with microwave energy, the differences in thermal conductivity of the Au NPs, the target crystals and water molecules produces a thermal gradient, 2) Kinetic energy of the Au NPs increases thereby affording the displacement of the Au NPs at high velocities, 3) High speed nanoparticles act as 'nano bullets' when they collide with the surface of crystals NPs) on the UA crystals is explained in the section below [33].…”

“…Glucocorticoid and corticosteroid treatments are affiliated with decreased immune function, osteoporosis, myopathy, avascular necrosis and cardiovascular diseases [16]. Non-drug based therapeutics that have been used as attached to a solid surface and result in a physical break down of the target crystals [33,35].…”