Sensitive determination of sulfonamides in environmental water by capillary electrophoresis coupled with both silvering detection window and in‐capillary optical fiber light‐emitting diode‐induced fluorescence detector

Abstract

A new detector, silvering detection window and in-capillary optical fiber light-emitting diode-induced fluorescence detector (SDW-ICOF-LED-IFD), is introduced for capillary electrophoresis (CE). The strategy of the work was that half surface of the detection window was coated with silver mirror, which could reflect the undetected fluorescence to the photomultiplier tube to be detected, consequently enhancing the detection sensitivity. Sulfonamides (SAs) are important antibiotics that achieved great applications in many fields. However, they pose a serious threat on the environment and human health when they enter into the environment. The SDW-ICOF-LED-IFD-CE system was used to determine fluorescein isothiocyanate (FITC)-labeled sulfadoxine (SDM), sulfaguanidine (SGD) and sulfamonomethoxine sodium (SMM-Na) in environmental water. The detection results obtained by the SDW-ICOF-LED-IFD-CE system were compared to those acquired by the CE with in-capillary optical fiber light-emitting diode-induced fluorescence detection (ICOF-LED-IFD-CE). The limits of detection (LODs) of SDW-ICOF-LED-IFD-CE and ICOF-LED-IFD-CE were 1.0-2.0 nM and 2.5-7.7 nM (S/N = 3), respectively. The intraday (n = 6) and interday (n = 6) precision of migration time and corresponding peak area for both types of CE were all less than 0.86% and 3.68%, respectively. The accuracy of the proposed method was judged by employing standard addition method, and recoveries obtained were in the range of 92.5-102.9%. The results indicated that the sensitivity of the SDW-ICOF-LED-IFD-CE system was improved, and that its reproducibility and accuracy were satisfactory. It was successfully applied to analyze SAs in environmental water.

Trends in sensitive detection and rapid removal of sulfonamides: A review

“…In general, a majority of experiments on sulfonamide analyses have been conducted by HPLC-MS/MS . Nevertheless, LC with different detectors, such as UV [71,72], fluorescence (FL) [73], and photodiode array detectors (DADs) [33,74,75] are also common.…”

“…Sulfonamides are a series of amphoteric molecules that have a strong polarity and thermal instability [137,138]; thus, HPLC is typically utilized for the separation of different kinds of sulfonamides with its excellent separation capacity. Detectors coupled with HPLC include UV [71,72], FL [73], DAD [33,74,75], and MS [52,55,139,140]. Among these, the UV detector was most widely used for its inexpensiveness and utility, and the wavelengths of sulfonamides are from 270 to 280 nm or at 255 nm [106].…”

Analysis of antibiotics by CE and CEC and their use as chiral selectors: An update

“…In addition to UV and MS detection, other detection systems have been used in CE in the period of time reviewed in this article with the aim of determining different types of antibiotics. LIF , light emitting diode‐induced fluorescence detector (LED‐FLD), , photoluminescence , chemiluminescence , ECL , amperometric detection (AD) , and C 4 D were employed (see Table ).…”

“…They are small in size, low cost, they have wide range of emission wavelengths, long service life and low power consumption. As shown in Table , two articles were published in the period reviewed in this article dealing with the analysis of antibiotics by CE using LEDs .…”

“…A new detector, called silvering detection window in‐column optical fiber light‐LED‐FLD (ICOF‐LED‐FLD) was introduced by Ji et al. to enhance the detection sensitivity in CE . In this case, half of the surface of the detection window was coated with a silver mirror, which can reflect the fluorescence not detected by the photomultiplier tube, increasing the detection sensitivity obtained.…”