Executive Summary : | The global market for perfumes is very promising and is likely to grow further. This is mainly due to the development of exotic fragrances and their continued release for a long time period. However, the side-effects due to the chemical nature of such fragrance formulations are expected to hinder the growth of the global perfume market. Being hydrophobic in nature, fragrance molecules are required to be dispersed in organic solvents or required to be encapsulated in a shell of a material, which can offer prolonged release. Although the combination of preferred organic solvent and microplastic based shell material is able to achieve the prolonged release of the fragrance molecules, they are increasingly viewed as an environmental threat due to their non-biodegradable nature. Therefore, an alternative to this approach is desired, which can offer environmentally benign at a relatively lower cost and biodegradable fragrance formulations.
We propose to develop in-situ encapsulation method of fragrance molecules in water-dispersible hollow microspheres with hydrophobic pore internals using high internal phase emulsion (HIPE) templating. In the proposed work, the encapsulating material consists of hollow microspheres (based on silica) whose size, shell thickness and porosity can be controlled by optimizing the reaction conditions of film formation at the oil-water interface. With the hydrophobic shell internals, it is easy to retain the hydrophobic active molecules (fragrance molecules) inside the shell for a long time. With the external shell hydrophilic, it becomes easy to disperse them in water, thus avoiding the use of organic solvents for fragrance formulations. Thus, this approach is likely to produce environmentally benign and biodegradable formulations simultaneously.
The material prepared using such protocol is likely to be an alternative to the currently practiced microplastic based system (which are mostly non-biodegradable). The proposed materials would find many applications not only in fragrance formulations but also in controlled drug release, which is a thrust area in drug formulations. Further, this could be a promising solution for the development of low-cost mosquito repellants, of course, without the requirement of any additional external source of energy for the active molecules to vaporize. On another front, this material can be a good candidate in heterogeneous catalysis too, typically in cases where the reactant is oil soluble and the catalysis is water soluble. Further, carrying out such reactions in a continuous mode can also be realized with such materials. Thus, this material is likely to attract a much wider attention of the scientists/industries working in different areas of perfumery, drug delivery, food and flavors, and catalysis. |