Cocrystallization Acyclovir-Succinic Acid Using Solvent Evaporation Methods

Abstract

Objective: The aim of this research is to prepare and characterize cocrystals of acyclovir through cocrystallization of acyclovir-succinic acid (AS) to improve the physical properties of the drug.Methods: AS cocrystals were prepared using solvent evaporation method. The cocrystals were characterized by polarization microscope, scanning electron microscopy (SEM), differential scanning calorimetry, powder X-ray diffraction (PXRD), and Fourier transform infrared spectroscopy.Results: Physical characterization using polarization microscope and SEM showed the AS cocrystals have unique crystal habit and morphology. Phase diagram at a molar ratio of 50:50% (acyclovir:succinic acid) showed a decrease in the melting temperature, i.e., 176.23°C in comparison with the melting point of the constituent materials (acyclovir 253.53°C and succinic acid 187.29°C). The PXRD pattern of AS cocrystals (ethanol) exhibited new diffraction peaks at 2θ=5.91°; 9.16°; and 13.40°. Besides, cocrystals of AS (glacial acetic acid) indicated new peaks at 2θ=5.98°; 9.19°; and 13.43°. Furthermore, there was a shift in the N-H, O-H, and C=O. Conclusion:Cocrystallization of AS acid in ethanol and glacial acetic acid were successfully formed using solvent evaporation methods.

Preparation of Acyclovir-Isonicotinamide Cocrystal by Solvent Evaporation Method With Methanol and Isopropanol

“…Thermogram (Figure 1) shows different peaks between acyclovir, isonicotinamide, physical mixture, and cocrystal. Sharp exothermic peaks were formed of methanol and isopropanol cocrystal at 183.31 ° C and 186.24 ° C. This exothermic peak is caused by decomposition in the form of oxidation from cocrystal [12]. While the endothermic peak in methanol cocrystal and isopropanol cocrystal at 107.09°C and 109.10°C is caused by crystalline water that evaporates at that temperature or dehydration occurs [13,14].…”

Modification of Physicochemical Properties of Active Pharmaceutical Ingredient by Pharmaceutical Co-Crystals

“…Additionally, the solution region was expanded in the presence of ultrasound, while the stability regions for pure caffeine and maleic acid in water were contracted. Maleic acid and caffeine solubility as well as the stability of co-crystal forms in water were found to be related to the observed effect of ultrasound on the phase diagram [94]. Dwi Setyawan et al analysed the physicochemical characteristics and in vitro dissolution profile of co-crystals of quercetin and malonic acid made by solvent-drop grinding.…”