Determination of cholic acid in body fluids by β-cyclodextrin-modified N-doped carbon dot fluorescent probes

An easy, dependable, and sensitive cholic acid activity experiment was designed based on beta-cyclodextrin-modified carbon dot (beta-CD-CD) nanoprobes with specific host-guest recognizing ability and photoelectron transfer capability. The beta-CD-CD nanoprobes were characterized by infrared, ultraviolet-visible, and fluorescence spectroscopy and transmission electron microscopy. The fluorescence of the probes under optimized conditions linearly responded to cholic acid concentration from 0 to 650 mu mol.L-1 with a detection limit of 25 nmol.L-1. The probes also performed well in detecting cholic acid in serum and urine samples with an average recovery rate of 97.1%-103.4%. Thus, this study provides a reliable, rapid, and easy method of cholic acid detection in body fluids that can be potentially applied in medical studies. (C) 2019 Elsevier B.V. All rights reserved.