Sensing and Bio-Sensing Research (Jun 2021)
Green synthesis of graphene quantum dots from Opuntia sp. extract and their application in phytic acid detection
Abstract
Phytic acid and phytate anions are among the principal reserves of phosphorus. A few methods have been used for their detection, but these methods require harsh conditions. In this work, graphene quantum dots are successfully synthesized by Opuntia sp. extract through a pyrolysis microwave treatment. This green synthesis method allows us to controllably obtain nanostructures with excellent dispersion and a narrow size distribution to use for detecting phosphates and phytic acid and amplifying fluorescence quenching at pH = 8.8. Their application allows for a one-step turn-off system. The quenching percentage for phytic acid (PA) detection is 53%, and the quenching percentages are 26 and 21% for sodium phosphate monobasic (SPMB) and sodium phosphate dibasic (SPDB), respectively. The Stern-Volmer analysis shows that static and dynamic quenching mechanics contribute to phytic acid quenching.