Development and characterization of a label-free method for detection of folic acid

Rapid inexpensive tests with single-used consumables for determination of folic acid are highly demanded in medicine, as this substance is a vital component for production of healthy body cells, DNA replication, and formation of a spinal cord of the fetus at pregnancy. In this study, we propose and demonstrate a method of label-free detection of folic acid based on the spectral-correlation interferometry approach. The proposed method exhibits subnanomolar limit of detection and a wide dynamic range that covers clinically relevant concentrations of folic acid in humans.