Nano-Bioconjugate Film from Aloe vera to Detect Hazardous Chemicals Used in Cosmetics

Abstract

It is of utmost importance to detect hazardous chemicals that affect human health. In this work, a simple method has been developed using a traditional medicinal herb Aloe vera as a carbon source to fabricate a nano-bioconjugate film. The nano-bioconjugate system comprises of A. vera gel itself and sodium alginate to form a fluorescent nano-bioconjugate film. The film was successfully used as an optical "turn-off" sensor in detecting analytes viz. para-Aminobenzoic acid (PABA), benzophenone, hydroquinone, and propylparaben, which are used in cosmetics and are listed as "red-listed" chemicals. The applicability of the fluorescent film in detecting these hazardous chemicals was even assessed with some locally purchased cosmetic samples. Mechanistic insight into the fluorescent quenching shown by nano-bioconjugate film is also discussed. Developments of such a detection system from sustainable sources make it an interesting option for fabricating sensors for hazardous chemicals.