Effect of surfactants and polymers on morphology and particle size of telmisartan in ultrasound-assisted anti-solvent crystallization

Abstract

The major challenge faced by the pharmaceutical industry is the aggregation of drug nanoparticles. Controlling the surface forces between the particles with the help of surfactants and polymers may overcome this problem. An attempt has been made to develop nanocrystals of the telmisartan to improve its solubility by applying an anti-solvent crystallization in the presence of surfactants, polymers, and ultrasound. Various surfactants (sodium lauryl sulfate, Tween 80) and polymers (polyvinylpyrrolidone K30, polyvinylpyrrolidone K90, polyethylene glycol 6000, and hydroxypropyl methyl cellulose) at different concentrations (0.2, 0.4, 0.6 and 0.8% w/w) with and without ultrasound were studied to observe their effect on particle size and morphology. It was observed that crystal size was found to be 290 nm and 181.7 nm for Tween 80 and polyvinylpyrrolidone K30, respectively, which was further reduced by ~ 35% and 9% in the presence of ultrasound. The possible interactions among telmisartan, surfactants, and polymers in the solid state were analyzed by Fourier transform infrared spectroscopy, X-ray diffraction patterns, and morphology by scanning electron microscope, respectively. It was found that raw telmisartan showed the rod-like morphology with the size range of 6–10 µm and the recrystallized drug showed acicular-shaped morphology with size range of 100–400 nm.