Deepak Sharma*, Arunabha Banik, S k Gupta
Department of Pharmaceutical Technology,
The Microspongesdelivery system are extremely small, inert,indestructibleclusters of even tinierspherical particles of microscopic sizepatented polymeric delivery systems consisting of porous microspheres that can entrap a wide range of active ingredients such as emollients, fragrances, essential oils, sunscreens, and anti-infective, anti-fungal, and anti-inflammatory agents and are very well tolerated, and highly efficacious, novel productsthat do not pass through the skin, capable of holding four times their weight in skin secretionsand can absorb skin secretions. Like a true sponge, each microspheres consists of a myriad of interconnecting voids within a non-collapsible structure with a large porous surface. The size of the microsponges can be varied usually from 5-300µm in diameter, depending upon the degree of smoothness or after-feel required for the end formula. Although the microsponge size may vary, a typical 25µm sphere can have up to 250000 pores and an internal pore structure equivalent to 10ft in length providing a total pore volume of about 1ml/g. This results in a large reservoir within each microsponge, which can be loaded with up to its own weight in active agent. The microsponge particles themselves are too large to be absorbed into the skin and this adds a measure of safety to these microsponge materials. Another safety concern is the potential bacterial contamination of the materials entrapped in the microsponge. Because the size of the pore diameter is smaller than bacteria, ranging from 0.007 to 0.2µm, bacteria cannot penetrate into the tunnel structure of the microsponges.The microsponge system can prevent excessive accumulation of ingredients within the epidermis and the dermis. Potentially, the microsponge system can reduce significantly the irritation of effective drugs without reducing their efficacy.