Electrochemical Cleavage of the Carbon-Boron Bond in p-Acetamidophenylboronic Acid at Neutral pH Conditions

Herein, it is reported that p-acetamidophenylboronic acid can be electrolytic cleavage of the carbon-boron bond to p-acetamidophenol at an electric potential of 1.2 V vs. Ag/AgCl in 100 mM phosphate buffer of pH 7.4 (containing 10% acetonirile). The electrochemical reaction was investigated by HPLC, LC with tandem mass spectrometry, and cyclic voltammetry. This electrochemical reaction could be useful in the development of electrical controlled drug delivery systems under neutral pH conditions.

Voltammetric pH Measurements Using Azure A-Containing Layer-by-Layer Film Immobilized Electrodes

pH is one of the most important properties associated with an aqueous solution and various pH measurement techniques are available. In this study, Azure A-modified poly(methacrylic acid) (AA-PMA) was synthesized used to prepare a layer-by-layer deposited film with poly(allylamine hydrochloride) (PAH) on a glassy carbon electrode via electrostatic interactions and the multilayer film-immobilized electrode was used to measure pH. Cyclic voltammetry (CV) and differential pulse voltammetry (DPV) measurement were performed. Consequently, the oxidation potential of AA on the electrode changed with pH. As per Nernst's equation, because H⁺ ions are involved in the redox reaction, the peak potential shifted depending on the pH of the solution. The peak potential shifts are easier to detect by DPV than CV measurement. Accordingly, using electrochemical responses, the pH was successfully measured in the pH range of 3 to 9, and the electrodes were usable for 50 repeated measurements. Moreover, these electrochemical responses were not affected by interfering substances.