New-generation bar adsorptive microextraction (BAµE) devices for a better eco-user-friendly analytical approach-Application for the determination of antidepressant pharmaceuticals in biological fluids.

The present contribution aims to design new-generation bar adsorptive microextraction (BAµE) devices that promote an innovative and much better user-friendly analytical approach. The novel BAµE devices were lab-made prepared having smaller dimensions by using flexible nylon-based supports (7.5 × 1.0 mm) coated with convenient sorbents (≈ 0.5 mg). This novel advance allows effective microextraction and back-extraction ('only single liquid desorption step') stages as well as interfacing enhancement with the instrumental systems dedicated for routine analysis. To evaluate the achievements of these improvements, four antidepressant agents (bupropion, citalopram, amitriptyline and trazodone) were used as model compounds in aqueous media combined with liquid chromatography (LC) systems. By using an N-vinylpyrrolidone based-polymer phase good selectivity and efficiency were obtained. Assays performed on 25 mL spiked aqueous samples, yielded average recoveries in between 67.8 ±â€¯12.4% (bupropion) and 88.3 ±â€¯12.1% (citalopram), under optimized experimental conditions. The analytical performance also showed convenient precision (RSD < 12%) and detection limits (50 ng L-1), as well as linear dynamic ranges (160-2000 ng L-1) with suitable determination coefficients (r2 > 0.9820). The application of the proposed analytical approach on biological fluids showed negligible matrix effects by using the standard addition methodology. From the data obtained, the new-generation BAµE devices presented herein provide an innovative and robust analytical cycle, are simple to prepare, cost-effective, user-friendly and compatible with the current LC autosampler systems. Furthermore, the novel devices were designed to be disposable and used together with negligible amounts of organic solvents (100 µL) during back-extraction, in compliance with the green analytical chemistry principles. In short, the new-generation BAµE devices showed to be an eco-user-friendly approach for trace analysis of priority compounds in biological fluids and a versatile alternative over other well-stablished sorption-based microextraction techniques.

Enhancement for trace analysis of sulfonamide antibiotics in water matrices using bar adsorptive microextraction (BAµE).

In this study, the enhancement for trace analysis of sulfonamide antibiotics (sulfathiazole, sulfamethoxazole and sulfadimethoxine) and trimethoprim in water matrices is proposed using bar adsorptive microextraction combined with micro-liquid desorption followed by high-performance liquid chromatography with diode array detection (BAµE-µLD/HPLC-DAD). By comparing different polymers and activated carbons as sorbent coatings for BAµE, the polystyrene-divinylbenzene polymer (PS-DVB) showed the best selectivity for the compounds under study. Assays performed through BAµE(PS-DVB)-µLD on 25mL of ultrapure water samples spiked at the 8.0µgL(-1) level showed recoveries ranging from 63.8±1.5% to 84.2±1.9%, under optimized experimental conditions. The validated method provided satisfactory limits of detection (0.08-0.16µgL(-1)) and good linear dynamic ranges (0.16-8.00µgL(-1)) with determination coefficients higher than 0.9958. The proposed analytical methodology was applied to real matrices, such as tap, estuarine and wastewater samples using the standard addition method. It showed to be easy to implement, with good reproducibility, sensitivity and requiring small amount of sample. Furthermore, negligible consumption of organic solvents was used in compliance with the green analytical chemistry principles. When compared to other well-established microextraction approaches, BAµE demonstrated better performance concerning recovery yields and sensitivity.

Multibiomarker in fish to evaluate a river used to water public supply.

We aimed to evaluate the ecological integrity of a large river, which receives agricultural and urban effluents and is used to water public supply. The fish species Astyanax bifasciatus was used as bioindicator during winter and spring 2012, and summer 2013 at the Middle Iguaçu River basin in Paraná state, Brazil. Water chemical and physical measures and ecotoxicological tests were carried out as well biochemical and genetic biomarkers in sampled fish in each period. The studied area was divided in three sample points: SP1, located where the water is collected to public supply; SP2, located in an urbanized area, and SP3, located at an urbanized area with the discharge of the sewage treatment. Although water chemical and physical analyzes were range of the Brazilian law to hydric bodies, anticholinesterasic effects were found in winter, oxidative stress in summer and spring. The higher genotoxic effect was in winter to all sample points. The temporal variation in biomarkers and the detection of caffeine in the water call attention to the water quality in this river mainly to be used to public supply.