Analysis of short‐chain aliphatic amines in food and water samples using a near infrared cyanine 1‐(ε‐succinimydyl‐hexanoate)‐1′‐methyl‐3,3,3′,3′‐tetramethyl‐indocarbocyanine‐5,5′‐disulfonate potassium with CE–LIF detection

Abstract

Precolumn derivatization of six short-chain aliphatic amines by a near-infrared dye, 1-(ε-succinimydyl-hexanoate)-1'-methyl-3,3,3',3'-tetramethyl-indocarbocyanine-5,5'- disulfonate potassium (MeCy5-OSu), followed by MEKC-CE-LIF detection has been developed as a method for the determination of aliphatic amines in environmental water and food. Optimum derivatization was operated nicely in pH 9.0 borate buffer at 20°C for 30 min. Well separated peaks were observed with a pH 9.5 BGE containing 10 mmol L⁻¹ phosphoric acid, 20 mmol L⁻¹ SDS, and 7% methanol buffered with 1.0 mol L⁻¹ NaOH. The separation procedure was rapidly achieved within 11 min and the matrix interferences could be effectively eliminated. A linear calibration graph was obtained for 5-200 nmol L⁻¹ analytes with a correlation coefficient in the range 0.9933-0.9995 for amines. This method was successfully utilized to determine aliphatic amines in lake, sewage water, and red wine with recoveries ranging from 96.4 to 105% and the RSDs ranging from 0.9 to 2.9%. Near-infrared, LIF-detector-compatible MeCy5-OSu was proved suitable for the accurate, sensitive, and rapid separation and determination of aliphatic amines in water and food samples.

Low-Temperature Microchip Nonaqueous Capillary Electrophoresis of Aliphatic Primary Amines: Applications to Titan Chemistry

“…The limits of detection (LODs) (Table ) ranged from 1.0 nM to 2.6 nM for all primary amines investigated, with the exception of ethylamine; the limit of detection of ethylamine (C2) could not be accurately determined, because of contamination from triethylamine. These values are within the range of reported detection limits for similar μCE–LIF protocols in aqueous solution, both for short-chain aliphatic primary amines up to C6 (0.6–2 nM), and other functional groups, such as aldehydes (0.7 nM), ketones (5 nM), and carboxylic acids (5–10 nM) . In nonaqueous solution, we note that short- and long-chain fatty acids up to C20 have been detected using NACE in acetonitrile/water mixtures with comparable sensitivity (6.5 nM) …”

“…Although μCE separations of short-chain aliphatic amines up to C6 in aqueous solutions report resolutions of one methyl unit, , compounds with chain lengths longer than ∼C12 are not soluble in aqueous solution and therefore cannot be detected by any aqueous-based technique such as capillary zone μCE (see Figure S5 in the Supporting Information). However, when considering in situ analysis on Titan, where organics range from small to very large, on the order of several hundred to thousands of Daltons, the ideal technique should be capable of separating both short- and long-chain species.…”

Recent advances in the application of capillary electromigration methods for food analysis and Foodomics

“…In another application, a CE‐LIF method was developed to analyze six aliphatic amines (methylamine, ethylamine, n ‐propylamine, n ‐butylamine, n ‐pentylamine, and n ‐hexylamine) labeled with MeCy5‐OSu within 11 min . The method was successfully applied to the analysis of environmental (lake water and sewage water) and food (wine) samples.…”

Rapid and sensitive determination of free thiols by capillary zone electrophoresis with near‐infrared laser‐induced fluorescence detection using a new BODIPY‐based probe as labeling reagent

“…After derivatization procedure, DMDSPAB‐I and the resultant derivative solutions could be stable at least 10 h at room temperature under daylight with a change in peak areas less than 5%, which means DMDSPAB‐I and its thiol derivatives have excellent stabilities for CE and their treatment is easy and need not be kept in dark. While for cyanines, the most commonly used fluorophore for laser line of 635 nm, the poor stability is always a problem, and all the reagent solutions have to be kept in dark, moreover, it needs adding solid reagents during the derivatization procedure when necessary .…”