Pre-formulation strategy for liposome encapsulation of new thioctic acid conjugates for enhanced chemical stability and efficient drug carrier for MPO-Mediated atherosclerotic CVD treatment
Lipoyl-apocynin and lipoyl-sesamol are bio-active conjugates of thioctic acid (also known as alpha-lipoic acid), synthesized by benign chemical approach by the combination of thioctic acid and powerful bio-phytonutrients, apocynin and sesamol respectively. Encapsulation is done for chemically modified thioctic acid conjugates within liposome structure as a possible drug carrier for targeted site delivery without chemical degradation useful in myeloperoxidase (MPO) mediated atherosclerotic cardiovascular disease (CVD) treatment. Development of facile process route to thioctic acid conjugates with complete chemical characterization and bio-encapsulation of these chemical entities in a liposome sphere and establish encapsulation efficiency, zeta potential, vesicle size, surface morphology, and long-term sustained stability. The liposome conjugates are also characterized by critical in vitro experiments. The encapsulation efficiency of thioctic acid conjugates is found to be nearly 70%. Besides, vesicle size and zeta potential are also measured for formulated thioctic acid products. The chromatographic evaluation of encapsulated products reveals that liposomes seem to protect thioctic acid conjugates when it is incubated in simulated body fluid, preventing ester hydrolysis, thereby offering chemical stability to the thioctic acid conjugates. Liposome loaded conjugates are also established to be potent agents for MPO mediated atherosclerotic CVD in a relevant preclinical in vitro test. This is the first report on a highly efficient and sustainable chemical method for liposomal encapsulation of thioctic acid conjugates of apocynin and sesamol useful for MPO-mediated atherosclerotic CVD treatment substantiated by relevant in vitro assays.