Detection Of Sulfamethoxazole Research Articles

SERS-TLC Device for Simultaneous Determination of Sulfamethoxazole and Trimethoprim in Milk

The aim of this work is to develop a device based on thin-layer chromatography coupled with surface-enhanced Raman spectroscopy (TLC-SERS) to analyze sulfamethoxazole (SMX) and trimethoprim (TMP) in commercial milk samples using chemometric tools. Samples were eluted in TLC plates, and a central composite design (CCD) of two factors was performed to optimize the gold nanoparticle dispersion on TLC plates for SERS, aiming at the detection of both drugs at concentrations close to their maximum residual limits (MRLs). Following the optimization, hyperspectral images from the SERS were captured of the TLC plates. Multivariate curve resolution (MCR-ALS) and independent component analysis (ICA) chemometric techniques were used to extract the signals of the analytes. All the samples presented recovery values of 81–128% for TMP. The quantification of SMX was not possible due to SERS suppression by an interferent. However, it was possible to detect SMX at a concentration of two times the MRL (8.0 × 10−7 mol·L−1). The results demonstrate that the TLC-SERS device is a potential tool for the quantification of TMP and the detection of SMX in milk.

A stimuli response, core-shell structured and surface molecularly imprinted polymers with specific pH for rapid and selective detection of sulfamethoxazole from milk sample

In this study, a novel kind of pH-responsive, magnetic and core-shell structured molecularly imprinted polymer (pH-MMIPs) was synthesized for the selective recognition of sulfamethoxazole (SMX). It was synthesized by way of surface imprinting and free radical polymerization. The composition and structure of pH-MMIPs has magnetic nanoparticles as its core, a thin imprinted polymer layer as its shell using 2-(Dimethylamino) ethyl methacrylate and 4-vinylphenylbronic acid as the pH-sensitive monomers, and SMX as template molecule. Interestingly, the pH-MMIPs could control the capture/release process in the selective recognition and detection of SMX by changing the pH value. Evaluation of the property of pH-MMIPs through series of adsorption experiments showed that it has an adsorption capacity of 25.41 mg·g−1 with a very rapid speed of magnetic separation. Additionally, it was successfully applied to selectively detect SMX in real milk samples, and the recoveries was in ranges of 89.7% and 98.2%. This study provides a new method and idea for the selective separation of SMX residue in food using molecularly imprinted polymers with pH- response and identification.

SERS as an analytical tool in environmental science: The detection of sulfamethoxazole in the nanomolar range by applying a microfluidic cartridge setup

Sulfamethoxazole (SMX) is a commonly applied antibiotic for treating urinary tract infections; however, allergic reactions and skin eczema are known side effects that are observed for all sulfonamides. Today, this molecule is present in drinking and surface water sources. The allowed concentration in tap water is 2·10−7 mol L−1. SMX could unintentionally be ingested by healthy people when drinking contaminated tap water, representing unnecessary drug intake. To assess the quality of tap water, fast, specific and sensitive detection methods are required, in which consequence measures for improving the purification of water might be initiated in the short term. Herein, the quantitative detection of SMX down to environmentally and physiologically relevant concentrations in the nanomolar range by employing surface-enhanced Raman spectroscopy (SERS) and a microfluidic cartridge system is presented. By applying surface-water samples as matrices, the detection of SMX down to 2.2·10−9 mol L−1 is achieved, which illustrates the great potential of our proposed method in environmental science.

Leaching of Pharmaceuticals and Personal Care Products in Turfgrass Soils during Recycled Water Irrigation

An important beneficial reuse of treated wastewater (recycled water) in arid and semiarid regions is landscape irrigation. However, the environmental fate, especially groundwater contamination potential, of trace contaminants such as pharmaceuticals and personal care products (PPCPs) is a significant concern that can hinder the acceptance and adoption of such reuses. In this study, we irrigated mature turfgrass plots with nonspiked tertiary treated wastewater for over 6 mo at 100 or 130% of the reference evapotranspiration rate (ETo) and collected leachate water at the 90-cm depth on a weekly basis. In the recycled water, all 14 target PPCPs were consistently found, and the mean levels of atenolol, gemfibrozil, meprobamate, carbamazepine, and sulfamethoxazole were above 100 ng L. However, only five compounds were detected in the leachate at trace levels. Trimethoprim and primidone were frequently found, whereas the detection of sulfamethoxazole, meprobamate and carbamazepine was less frequent (<50%). When detected, the overall mean concentration in the leachate was 10.2 ng L for trimethoprim, 7.1 ng L for primidone, and 2.9 to 12.4 ng L for carbamazepine, sulfamethoxazole, and meprobamate. The majority of the target PPCPs were completely removed. Given that the irrigation rates were higher than normal, this study clearly demonstrated the efficacy of turfgrass systems in attenuating PPCPs during recycled water irrigation. However, it is also apparent that some PPCPs are more susceptible to leaching than others, and these PPCPs thus merit further research attention.

A hard–soft microfluidic-based biosensor flow cell for SPR imaging application

An ideal microfluidic-based biosensor flow cell should have not only a “soft” interface for high strength sealing with biosensing chips, but also “hard” macro-to-micro interface for tubing connection. Since these properties are exclusive of each other, no one material can provide the advantages of both. In this paper, we explore the application of a SiO 2 thin film, deposited by plasma-enhanced chemical vapor deposition (PECVD) technology, as an intermediate layer for irreversibly adhering polydimethylsiloxane (PDMS) to plastic substrate, and develop a hard–soft, compact, robust microfluidic-based biosensor flow cell for the multi-array immunoassay application of surface plasmon resonance (SPR) imaging. This hard–soft biosensor flow cell consists of one rigid, computer numerically controlled (CNC)-machined poly(methyl methacrylate) (PMMA) base coated with a 200 nm thick SiO 2 thin film, and one soft PDMS microfluidic layer. This novel microfluidic-based biosensor flow cell does not only keep the original advantage of conventional PDMS-based biosensor flow cell such as the intrinsically soft interface, easy-to-fabrication, and low cost, but also has a rigid, robust, easy-to-use interface to tubing connection and can be operated up to 185 kPa in aqueous environments without failure. Its application was successfully demonstrated with two types of experiments by coupling with SPR imaging biosensor: the real-time monitoring of the immunoglobulin G (IgG) interaction, as well as the detection of sulfamethoxazole (SMOZ) and sulfamethazine (SMZ) with the sensitivity of 3.5 and 0.6 ng/mL, respectively. This novel hard–soft microfluidic device is also useful for a variety of other biosensor flow cells.

Simple analytical model of biosensor competition analysis for detection of low-molecular-weight analytes

A steady-state model of competition inhibitor analysis and its application to the detection of sulfamethoxazole in aqueous solutions (0.01–100 μg/mL) using surface plasmon resonance are examined. An analytical expression (logistic curve) relating the equilibrium response of the biosensor to the concentration of the low-molecular-weight analyte, its immobilized analogue, and the biological receptor was obtained.