Polymer increases potency of curcumin and pain drug combo
doi:10.1038/nindia.2020.61 Published online 11 April 2020
Researchers have made a polymer-coated nanoformulation using nanoparticles of curcumin and indomethacin, a pain-relieving drug1. They have shown that the coat made of chitosan, a natural polymer found in the shells of shrimps, enhanced the therapeutic efficacy of curcumin and the drug.
Previous studies had shown that curcumin checks inflammation, stops growth of cancer cells and even protects cells against free-radical-induced damage. Despite its medicinal values, pure curcumin is not soluble in water. It is also not bioavailable in its free form.
To overcome this, the scientists from the Indian Institute of Technology in Mandi and the Indian Association for the Cultivation of Science in Kolkata synthesised the nanoformulation using chitosan-coated nanoparticles of curcumin and indomethacin. They then studied the nanoformulation’s efficiency in releasing curcumin and the drug, and its stability during storage.
Chitosan is known to repel water. It wraps around the curcumin nanoparticles and prevents these particles from sticking to one another and forming crystals. The nanoformulation, the researchers report, did not recrystalise even after being stored for one year.
The nanoformulation converts itself from a water-repelling entity to a water-loving one when it binds to hydrogen ions in a solution. This allows the nanoformulation to release the drug at a faster rate, depending on the pH levels of various solutions.
This, the researchers say, is expected to increase the chances of direct absorption of curcumin and the drug through the intestine after oral intake, and the safe delivery of curcumin to target tissues.
1. Sharma, K. et al. Molecular distribution of indomethacin: impact on the precipitation of glassy curcumin pH-responsive nanoparticles with enhanced solubility. Cryst. Growth. Des. (2020) doi:10.1021/acs.cgd.9b01550