Solar energy-based electromembrane extraction using agarose gel for the determination of nonsteroidal anti-inflammatory drugs from biological samples: An environmentally friendly strategy.

This paper presents the application of solar energy as a renewable resource in gel electromembrane extraction (G-EME). The extraction driving force (electrical field) generated from solar energy is stored through photovoltaic panels and significantly contributes to reducing the emission of greenhouse gasses. Moreover, the replacement of the polypropylene membrane and organic extracting solvents with biodegradable agarose membrane and the aqueous extracting solutions makes the presented approach compatible with the principles of green chemistry. Naproxen (NAP) and ibuprofen (IBF) were extracted from urine samples to the aqueous acceptor phase containing an anode electrode situated on the other side of the agarose gel membrane. Acceptable linearity was obtained in the concentration ranges of 6-100 and 9-100 µg. L - 1 with detection limits of 2 and 3 µg. L - 1 for NAP and IBF, respectively.

Electromembrane extraction using biodegradable deep eutectic solvents and agarose gel as green and organic solvent-free strategies for the determination of polar and non-polar bases drugs from biological samples: A comparative study.

Two modes of electromembrane extraction (EME) were evaluated in this work, one using deep eutectic solvents (DESs) as liquid membrane, and another was gel electromembrane extraction (G-EME) based on solid agarose membrane. Both EME modes have eliminated organic solvents and are recognized as green strategies. Unlike classic EME in which polypropylene membrane and organic extracting solvents play an essential role in the extraction process, new modes of EME are based on biodegradable membranes and aqueous extracting solutions. Approaches of EME based on the new designs follow the green chemistry principles. Each mode of EME was evaluated for the determination of polar and non-polar bases drugs from human urine samples using high-performance liquid chromatography (HPLC) equipped with a diode array detector (DAD). EME using DES A was suitable for determining polar and non-polar bases drugs in a large polarity window. While extraction recoveries for all six drugs studied by G-EME were lower than EME using DES A. Comparing the two EME modes shows similar results in the analytical figures of merit. However, differences in extraction recoveries of the drugs by two EME modes were observed which is related to the difference in membranes structure. Our findings indicate that the differences between membranes properties used in two EME modes, including the permeability, hydrophilicity, hydrophobicity, and variety of interactions, are influencer factors on extraction efficiency. The two EME modes provided good linearity in the ranges of 16-100 and 19-100 µg. L-1 for G-EME and EME using DES A, respectively with (r2 > 0.993). Also, the detection limits (LODs) were 19-32 and 19-29 µg. L-1 for G-EME and EME using DES A, respectively.

Enrichment of psychotropic drugs using rhamnolipid bioaggregates after electromembrane extraction based on an agarose gel using a rotating electrode as a green and organic solvent-free strategy.

We here present an efficient approach for the tandem extraction of psychotropic drugs using biodegradable materials. In this regard, gel electromembrane extraction (G-EME) was combined with the emulsification-based microextraction (ME) technique by rhamnolipid bioaggregates as a green extraction approach. The tandem extraction technique consists of two stages: (i) extraction of psychotropic drugs from human urine samples to the acceptor phase situated on the other side of the agarose gel membrane, and (ii) transfer of analytes from the acceptor phase into a colloidal phase of rhamnolipid biosurfactants. The colloidal phase was formed by adding rhamnolipid biosurfactants to the extracted phase of the first step. The colloidal phase was finally injected into a liquid chromatographic system for quantitative analysis. G-EME mechanism is based on electrokinetic migration of charged species toward oppositely charged electrode located in the acceptor solution under the influence of the electric field. After extraction, the analytes were trapped in an emulsion phase floating on the surface of the solution and at the end were injected into the liquid chromatographic system. The method provided good linearity in the ranges of 5-100 and 10-100 µg. L-1 for methamphetamine and amphetamine, respectively with (r2 > 0.992). Also, the detection limits (LODs) were 1 and 5 µg. L-1 for methamphetamine and amphetamine, respectively. The mean extraction recoveries by G-EME-ME for real samples at three spiked concentrations were in the range 95.9-101.1% and complete analytical workflow within only 18 min.

Bio-dispersive liquid liquid microextraction based on nano rhaminolipid aggregates combined with magnetic solid phase extraction using Fe3O4@PPy magnetic nanoparticles for the determination of methamphetamine in human urine.

In the present investigation, extraction and preconcentration of methamphetamine in human urine samples was carried out using a novel bio-dispersive liquid liquid microextraction (Bio-DLLME) technique coupled with magnetic solid phase extraction (MSPE). Bio-DLLME is a kind of microextraction technique based nano-materials which have potential capabilities in many application fields. Bio-DLLME is based on the use of a binary part system consisting of methanol and nano rhaminolipid biosurfactant. Use of this binary mixture is ecologically accepted due to their specificity, biocompatibility and biodegradable nature. The potential of nano rhaminolipid biosurfactant as a biological agent in the extraction of organic compounds has been investigated in recent years. They are able to partition at the oil/water interfaces and reduce the interfacial tension in order to increase solubility of hydrocarbons. The properties of the prepared Fe3O4@PPy magnetic nanoparticles were characterized using Fourier transform infrared spectroscopy and X-ray diffraction methods The influences of the experimental parameters on the quantitative recovery of analyte were investigated. Under optimized conditions, the enrichment factor was 310, the calibration graph was linear in the methamphetamine concentration range from 1 to 60µgL-1, with a correlation coefficient of 0.9998. The relative standard deviations for six replicate measurements was 5.2%.

Biosorption-based dispersive liquid-liquid microextraction combined with polypyrrole-coated magnetic nanoparticles as an effective sorbent for the extraction of ibuprofen from water samples using magnetic solid-phase extraction.

In this paper, biosorption-based dispersive liquid-liquid microextraction (BioDLLME) in combination with magnetic solid-phase extraction (MSPE) has been developed as a sample pretreatment method with high enrichment factor for the sensitive determination of ibuprofen in water samples. At first, magnetic Fe3 O4 /polypyrrole nanoparticles were synthesized and employed as sorbent for the MSPE of ibuprofen. After the elution of the desired compound from the sorbent by using methanol, BioDLLME technique was performed on the obtained solution. After MSPE, the eluent of MSPE was used as the disperser solvent for BioDLLME, so that the extra preconcentration factor could be achieved. The properties of the prepared magnetic sorbent were characterized using field emission scanning electron microscopy, Fourier transform infrared spectroscopy and X-ray diffraction methods. Experimental parameters affecting the extraction efficiency were studied and optimized. Under optimum conditions, the enrichment factor was 274. The linear dynamic range and limit of detection are 0.25-80 and 0.083 µg/L, respectively. The relative standard deviations for six replicate measurements are 3.82%.

Bio-sorption based dispersive liquid-liquid microextraction for the highly efficient enrichment of trace-level bisphenol A from water samples prior to its determination by HPLC.

In this study, biosorption based dispersive liquid liquid microextraction (Bio-DLLME) has been developed as a new method for the extraction of bisphenol A (BPA) from water samples. In this technique, the BPA is extracted into a stable cloudy phase. The colloidal phase is composed of micro-particles made from rhaminolipid biosurfactant and methanol, which dispersed in the water samples and facilitated the breakdown of analyte matrix bonds and provided high extraction yields. Rhaminolipid biosurfactants form a thin molecular interfacial film. This layer is formed between donor and recipient phase. This molecular layer, lowers the interfacial tension between immiscible phases (aqueous solution: colloidal particles) and allow dissimilar phases to mix and interact more easily. So the equilibrium state is achieved quickly and, therefore, the extraction time is very short. The attraction of the proposed method is that the extraction is fast, simple and can be done without toxic organic solvents. Also bioaggregates have several advantages such as higher environmental compatibility and biodegradability. Experimental parameters affecting the extraction efficiency were studied and optimized. Under the optimum conditions, relative recoveries of BPA were in the ranges of 98-103.3%. The calibration plot is linear in the range between 1 and 1000µgL(-1) (R(2)=0.998), and the relative standard deviation (RSD, for n=6) is 3.24%.

New strategy for the biosorption of atrazine after magnetic solid-phase extraction from water followed by high-performance liquid chromatography analysis.

We describe a rapid and simple microextraction of atrazine from water samples. This method is based on the use of magnetic nanoparticles as sorbents and bioaggregates that are applied to the extraction and preconcentration of atrazine. The resulting magnetic nanoparticles possess a fast adsorption kinetics and high adsorption capacity. Bioaggregates made up of rhaminolipid biosurfactant were assessed as a new strategy for the sample treatment. The extractant was obtained from magnetic nanoparticles using the magnetic solid-phase extraction method. Then the target analyte was rapidly transferred from the sorbent surface to bioaggregates, which have a low toxicity and are green and ecofriendly. Finally, the extract is centrifuged and transferred to micro-syringe for analysis by high-performance liquid chromatography. Experimental parameters affecting the extraction efficiency were studied and optimized. Under optimum conditions the enrichment factor was 268. The linear dynamic range and limit of detection were 0.1-50 and 0.033 µg/L, respectively. The relative standard deviation for six replicate measurements was 5.3%. The results demonstrate good applicability of biosorption-assisted magnetic solid-phase extraction method for the determination of atrazine from water samples.