Ratiometric fluorimetric and colorimetric probe for sensing and imaging pH changes in living cells.

Cell, enzyme, and tissue activity in living organisms are closely related to intracellular pH. Detecting the changes of intracellular pH is important to understanding the physiological and pathological changes in the process of crucial cell metabolism. A pH probe (HTBI) based on hemicyanine was synthesized. The probe solution displayed a marked colour change from yellow to amaranth with the pH increase from neutral to basic; simultaneously, the emission spectra showed a significant red shift. The probe exhibited a ratiometric fluorescence emission (F586nm /F542nm ) characteristic of pKa 8.82. As expected, HTBI exhibited high sensitivity and selectivity for pH, fine photostability, reversibility, and low cytotoxicity. Therefore, it would be a very useful tool for measuring the intracellular pH changes.

A chemiluminescence sensor array for discrimination of seven toxicants.

A chemiluminescence (CL) sensor array was developed based on 11 CL systems cross-combined by three luminescence reagents and four oxidants. Using the CL sensor array, we measured seven toxicants, including morphine, ketamine, diazepam, chlorpromazine, strychnine, paraquat, and fenpropathrin, which represent psychotropic drugs, sedatives and hypnotics, rodenticides, herbicides, and insecticides, respectively. The CL response pattern or 'fingerprints' were obtained for a given compound on the sensor array and then discriminated through principal component analysis. The established sensor array has been applied to real-life samples and the results showed that it possesses excellent discrimination.