Understanding the Photophysics of Curcumin Inside Nano-Containers: How to Monitor Incorporation and Release Using Fluorescent Techniques

Curcumin, a family member of Zingiberaceae, obtained from the rhizome of Curcuma longa L., also known as turmeric, is a most familiar ingredient in the Indian kitchen for making curries. Still, it has numerous medicinal benefits, even in cancer. As the stability of curcumin in water is low, it is mandatory to use a protective container to preserve and potentially deliver the curcumin. The micellar environment is different from bulk water and provides sufficient stability to curcumin leading to an excellent system to learn its physical and chemical properties. The hydrophobic environment inside the micelle controls curcumin’s photophysics, mainly the excited-state intramolecular proton transfer (ESIPT) that eventually leads to fluorescence intensity and lifetime changes. Fluorescence-spectroscopy could be an efficient tool to study the photophysics inside the nanocontainers and their release. Keeping this in mind, here we have described absorption as well as fluorescent techniques (ground and excited state) to understand the interaction of curcumin with micelles.