Enantiotropic Recognition of Methyl Valinate by Chiral Ion Selective Electrode Modified with Sodium Tetraphenylboron

Sodium tetraphenylboron (in a solution of w 4%) was chosen as a chiral selective recognizer and loaded on PVC membrane to prepare a chiral ion selective electrode, which was tested for its capability to recognize the enantiotropy of methyl valinate. It was shown that L-methyl valinate gives preferential response at this chiral ion-selective electrode. When testing in a buffer solution of pH 8.0 with internal reference solution of 0.1 mol·L-1 KCl, linear relationship between values of electrode response and concentration of L-methyl valinate was obtained in the range of 10-3-10-1mol·L-1 with slope of 47 mV·dec-1. The lower limit of determination found was 5.01×10-4mol·L-1. The potentiometric enantioselectivity coefficient of electrode (lgKpotL,D) found was -1.89.