The medical applications of biobased aerogels: ‘Natural aerogels for medical usage’

The biotechnology sector needs cost-effective, renewable, reusable and sustainable raw materials. There are many different biomaterials existed in this area, such as magnetic nanoparticles, silica, clay and polymers. But they have many disadvantages about cost, preparation conditions and toxic chemicals. Aerogel technology provides high added-value lightweight materials with huge porous structures high surface area and low density. The aerogels are classified into inorganic and organic according to the source of gel precursors. The inorganic aerogels are mostly prepared from alkoxides and various metal oxides. But either inorganic aerogels or first organic aerogels (resorcinol–formaldehyde) are composed of toxic chemicals that inherent them using in life science. Nowadays for preparing organic aerogels, natural precursors, such as polysaccharides (cellulose, chitosan, starch, alginate, carrageenan and curdlan) or proteins (silk fibroin and ovalbumin), milk (caseins and whey proteins, soy), are used and named as bioaerogels or biobased aerogels. All of these components are natural, biodegradable, bioactive and biocompatible for human. The biobased aerogels are mostly synthesized with polysaccharides. The natural polysaccharides and/or their derivatives can be used because of their availability, low toxicity, stability upon storage, good biological performance and enzyme-controlled biodegradability. Also, cellulose-based aerogels can be prepared using many renewable sources (wheat husk, potato tubers, paper waste, bagasse, etc) which is also very important for waste management. Biodegradable and biobased aerogels are of increasing pursuit, as the use of these compounds can be an alternative for reducing the impact on the environment. This mini review summarized the steps of preparation techniques of aerogels and explained the usage areas of biobased aerogels with examples of in drug delivery, wound healing and tissue engineering.