Trimethyl Chitosan Studied for Drug Delivery

Trimethyl Chitosan Studied for Drug Delivery
Derivative is more soluble than the basic molecule
Chitosan has been widely studied for pharmaceutical applications, but its usefulness has been restricted because of its limited solubility. Now researchers in India are studying trimethyl chitosan, a more soluble form, for pharmaceutical uses, including nanoformulations.

"Chitosan is not soluble in medium except below pH 5.6," said V.K. Mourya, PhD, a professor in the department of pharmaceutics at the Government College of Pharmacy in Aurangabad, India, in an e-mail to PFQ. "This limits its use as permeation enhancer in body compartments where pH is high."

These properties can be employed for drug delivery in the form of microparticles or nanoparticles.
V.K. Mourya, PhD, Government College of PharmacyDr. Mourya and a colleague recently reviewed the literature on trimethyl chitosan as a drug delivery vehicle. (Mourya VK, Inamdar NN. Trimethyl chitosan and its applications in drug delivery. J Mater Sci Mater Med. 2009;20(5):1057-1079.)

Like chitosan, trimethyl chitosan is positively charged and enhances drug transport via a paracellular route by opening the tight junctions between epithelial cells, Dr. Mourya said. Unlike chitosan, this quaternized derivative is soluble over a wide range of pH levels, he said. Its mucoadhesive properties may be advantageous, increasing the residence time of compounds in mucosal tissues.

"These properties can be employed for drug delivery in the form of microparticles or nanoparticles," Dr. Mourya said. "The role of trimethyl chitosan in DNA delivery is also promising."