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Microemulsion cleaning method has been proved to be an effective way to clean oily sludge with low interfacial tension and high solubilizing ability for non-miscible liquids. In this paper, the percentage range of the microemulsion in the formulation was obtained by studying phase behavior of the microemulsion. The response surface method was used to model and optimize the microemulsion to obtain the best formulation: n-BuOH content at 9.89%, NaCl content at 2.24% and AES/APG ratio at 3.75, and the oil removal rate reached 97.28%. Meanwhile, the cleaning conditions of oil sludge were also optimized by the response surface method and the optimal cleaning parameters were determined as liquid-solid ratio at 4.2, stirring rate at 157 r·min−1, and stirring time at 38 min. In addition, some experiments were carried out to confirm the simulation results, affording the oil removal rate of 98.79%. SEM and FTIR confirmed that the oil on the sludge can be removed by microemulsion. [ABSTRACT FROM AUTHOR]

An ultrasensitive and selective method for Bisphenol A (BPA) detection using aptamer-BPA and real-time quantitative polymerase chain reaction (RT-qPCR) technology is reported, in which biotin-modified aptamer DNA (BPA) is fixed on the inner wall of a streptavidin-coated PCR tube via biotin-avidin interactions and the template is fixed through the complementary base pairing with aptamer DNA. Upon the addition of BPA, the template DNA could be off from the inner wall of PCR tube, which results from aptamer DNA interacted specifically with BPA. Thus, the number of template DNA change result from the BPA concentration is readily seen by cycle threshold (Ct) values. The sensor exhibited an excellent linear response between Ct values and BPA concentration in the range of 1-500 nM and the detection limit of this method for aqueous BPA was as low as 0.7 nM. In addition, this method showed good selectivity for BPA over its analogues. [ABSTRACT FROM AUTHOR]

An effective and facile approach for mercury detection is essential for environmental protection and human health. In this study, we propose a novel strategy to develop a highly sensitive and selective method for the detection of mercury ions using real-time quantitative polymerase chain reaction (RT-qPCR) technology and the specific binding of Hg2+in thymine–thymine mismatch complexes. The signal for detection of Hg2+was generated using RT-qPCR amplification of a template strand of DNA. The sensor exhibited an excellent linear response between the cycle threshold (Ct) and mercury ion concentration in the range of 0.05–100 nM. Under optimised conditions, the detection limit of this method for aqueous Hg2+was as low as 30 pM. In addition, this system showed good selectivity for Hg2+over other metal ions. This new approach shows significant potential for detection of Hg2+in water and other samples. [ABSTRACT FROM PUBLISHER]

It is essential that the novel biomarkers discovered by means of advanced detection tools based on metabonomics could be used for long-term monitoring in food safety. By summarizing the common biomarkers discovery flowsheet based on metabonomics, this review evaluates the possible application of metabonomics in new biomarker discovery, especially in relation to food safety issues. Metabonomics have the advantages of decreasing detection limits and constant monitoring. Although metabonomics is still in the developmental stage, we believe that, based on its properties, such as noninvasiveness, sensitivity, and persistence, together with rigorous experimental designs, new and novel technologies, as well as increasingly accurate chemometrics and a relational database, metabonomics can demonstrate extensive application in food safety in the postgenome period. [ABSTRACT FROM PUBLISHER]

A rapid, sensitive, specific and simple method based on Fluorescence Polarization Immunoassay (FPIA) was developed for the quantitative detection of Bisphenol A in water. 4, 4-Bis (4-hydroxyphenyl) valeric acid (BHPVA) was selected as the hapten to produce the immunogen. Fluorescein-labeled Bisphenol A derivatives (tracers) with different structures were synthesized and purified by thin layer chromatography. Based on the polyclonal antibody and tracers, an optimized FPIA method was developed with a detection limit (10%% inhibition) of 2 μg L−1 and a linear working range of 20 to 800 μg L−1. FPIA was suitable for screening a large number of samples. The recoveries of fortified Tai lake water samples ranged from 91.85 to 102.78%%, and tap water samples ranged from 90.36 to 96.01%%. The coefficients of variation were all less than 20%%. This FPIA method, which did not require a complicated cleanup process, proved to be very useful for the screening of Bisphenol A in environmental water samples. [ABSTRACT FROM AUTHOR]