Spectrophotometric Determination of 1-(3-Dimethylaminopropyl)-3-ethylcarbodiimide Hydrochloride by Flow Injection Analysis

Abstract

1-(3-Dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (EDC·HCl) is a very useful agent to form amide bonds (peptide bonds) in an aqueous medium. A simple and fast detection system was developed using the reaction with pyridine and ethylenediamine in acidic aqueous solution and spectrophotometric flow injection analysis. The absorbances were measured at 400 nm and the reaction was accelerated at 40˚C. The calibration graph showed good linearity from 0 to 10% of EDC·HCl solutions: the regression equation was y = 3.15 × 10 4 x (y, peak area; x, % concentration of EDC·HCl). The RSD was under 1.0%. Sample throughput was 15 h -1 . This method was applied to monitoring the EDC·HCl concentration that remained after the anhydration of phthalic acid in water, esterification of acetic acid in methanol or dehydration condensation of malonic acid and ethylenediamine in water.

Determination of 1-(3-Dimethylaminopropyl)-3-ethylcarbodiimide Hydrochloride by Flow-Injection Analysis Based on a Specific Condensation Reaction between Malonic Acid and Ethylenediamine

“…In our previous work, 25 EDC·HCl with ethylenediamine and pyridine was detected at 400 nm, whose molar absorptivity (e) and regression equation were 0.014 L mol -1 cm -1 and y = 3.15 ¥ 10 4 x (y, peak area; x, % concentration of EDC·HCl), respectively. The LOD was 0.1%, which was low sensitivity.…”

“…The molar absorptivity (e), 665 L mol -1 cm -1 , of the product at 262 nm was larger than that of EDC·HCl, itself (0.014 L mol -1 cm -1 ), previously reported. 25 It was caused by the formation of a ring structure between malonic acid and ethylenediamine from a condensation reaction with EDC·HCl. The effective adsorption might be correlated with the resonance structure of the product, as shown in Fig.…”

“…The absorbance of the residual EDC·HCl (ring structure) decreased along with 390 ANALYTICAL SCIENCES MARCH 2009, VOL. 25 an increase in the concentration of the main product in the dehydration and etherification. However, the LOD of this method was not very good, 0.1%.…”

“…[22][23][24] It is caused by the stable ring structure of EDC·HCl itself in aquatic media, and it takes much time to react. In our previous work, 25 a simple and rapid FIA technique was developed for EDC·HCl determination by using an effective reaction with pyridine and ethylenediamine in acidic solution (0.1 M HCl). This method was then applied to the monitoring of the residual EDC·HCl concentration, which remained after the dehydration of phthalic acid in aqueous solution and the esterification of acetic acid in methanol.…”

Electrochemical Determination of Activity of Acetylcholinesterase Immobilized on Magnetic Particles

“…This work is focused on immobilization of AChE on the magnetic particles surface using EDC which was described to form amide bonds in aqueous medium [20], optimize square wave voltammetry method using PB-modified screen-printed electrode to observe AChE activity with and without presence of tacrine and also establish method´s interferences. It is expected that the assay will bring significant improvement to the current assays.…”