Ultrahigh Sensitivity Multifunctional Nanoprobe for the Detection of Hydroxyl Radical and Evaluation of Heavy Metal Induced Oxidative Stress in Live Hepatocyte

Hydroxyl radical ((OH)-O-center dot) is an important marker of the progress of heavy metal induced oxidative stress. However, most reported probes and detection methods cannot meet the need of monitoring the (OH)-O-center dot concentration within the whole progress because of the limited linear range. Besides, a low detection limit, high sensitivity, and good selectivity were also required. In this study, an ultrahigh sensitivity multifunctional nanoprobe (ICG-modified NaLuF4:Yb,Er) was developed to evaluate heavy metal induced oxidative stress by detecting (OH)-O-center dot concentration, with a colorimetric, upconversion luminescence, and photothermal stepped method. This method has a broad linear detection range, from 16 pM to 2 mu M, and a low detection limit of 4 pM. Besides, the nanoprobe showed less response to ions, amino acids, biomolecules, and other radical oxygen species (H2O2 and O-2(-) than (OH)-O-center dot. This highly selective, highly sensitive probe with a broad linear detection range has great potential utility for monitoring (OH)-O-center dot concentration in live hypatocyte within the progress of heavy metal induced oxidative stress, with probable in vivo applications in the future.