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A novel molecularly imprinted electrochemiluminescence (MIECL) sensor based on the luminescence of molecularly imprinted polymer-perovskite (MIP-CsPbBr

A modified quick, easy, cheap, effective, rugged, and safe (QuEChERS) sample preparation method coupled with gas chromatography–tandem mass spectrometry has been developed for the simultaneous analysis of amide/dinitroaniline/substituted urea herbicides in bivalve shellfish samples. A molecularly imprinted polymer (MIP) synthesized through bulk polymerization exhibited strong group–selective interactions with pigments, including β-carotene, chlorophyll A, and fucoxanthin, in bivalve shellfish extracts. Afterward, a modified QuEChERS method based on MIPs and primary and secondary amines was established to effectively remove matrix components in bivalve shellfish samples. Under the optimal conditions, good linearities were obtained in all of the analytes with R2 larger than 0.9995. Limits of quantification were in the range of 0.03–8.88 μg kg−1, respectively. The recoveries of all of the herbicides spiked at three concentrations of 10, 25, and 50 μg kg−1 in blank bivalve shellfish samples ranged from 81 to 109% with intra-day and inter-day relative standard deviations less than 8%, respectively. Results demonstrated that the proposed QuEChERS method coupled with GC–MS/MS was applied successfully to simultaneously determine 26 amide/dinitroaniline/substituted urea herbicides in bivalve shellfish.

A novel molecularly imprinted silica layer appended to FeSe quantum dots (MIP-FeSe-QDs) was fabricated and utilized as a recognition element to develop a selective and sensitive fluorescent nanosensor for cyfluthrin (CYF) determination. The MIP-FeSe-QDs were characterized by fluorescence spectrometry, scanning electron microscopy, transmission electron microscopy, and Fourier transform infrared spectroscopy. Excellent selectivity and high sensitivity of MIP-FeSe-QDs to CYF molecules were observed based on the fluorescence quenching of FeSe-QDs. Under optimal conditions, a good linear relationship was found between fluorescence quenching effect and increased CYF concentration within 0.010-0.20mg/L, with a correlation coefficient of 0.9911. The practicality of the developed sensor method for CYF detection in fish and sediment samples was further validated. Good recoveries ranging from 88.0% to 113.9% with

Two types of molecularly imprinted silica layers appended to quantum dots (MIP-QDs) for sulfonamides (SAs) were fabricated using reverse microemulsion surface grafting with 3-aminopropyltriethoxysilane as a functional monomer and sulfadimethoxine (SDM) and sulfadiazine (SDZ) as template molecules. The characterizations of both MIP-QDs were analyzed by ATR-FT-IR, SEM, and TEM, and their imprinting and specific fluorescence quenching mechanisms were elucidated through selectivity fluorescence response experiments. Finally, the MIP-QDs synthesized with SDZ as template exhibited excellent selective fluorescence quenching properties, which were attributed to the complementary imprinting cavities of the MIP-QDs to the templates and to the specific interactions between the functional monomer and the template molecules. Furthermore, a selective MIP-QD-based fluorescence optosensing sensor for the highly selective and sensitive recognition of SDZ was developed and successfully applied to detect SDZ in seawater and shrimp samples. Under optimal conditions, linear relationships with correlation coefficients 0.9971 were obtained along the range of 0.005–1.5 mg/L to SDZ. The limit of detection was 0.004 μg/L and 0.79 μg/kg for SDZ in seawater and shrimp samples, respectively. Excellent recoveries (82.7–99.9%) with a relative standard deviation (below 6.1%) were obtained for both samples spiked with three levels of SDZ. The proposed MIP-QD method provides a powerful tool for the rapid and sensitive determination of SDZ in real samples.

A modified quick, easy, cheap, effective, rugged, and safe (QuEChERS) procedure combined with GC-MS/MS detection approach using a dynamic multiple reaction monitoring (DMRM) mode was successfully applied for the simultaneous analysis of 84 polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) in shellfish samples. The novel molecular imprinted polymers (MIPs) were synthesized by precipitation polymerization and characterized by Scanning electron microscopy, Brunauer-Emmett-Teller, Fourier transform infrared spectra and adsorption experiment. The MIPs exhibited good adsorption capability to pigment coextractives in shellfish samples without the loss of analytes compared with other sorbents. Under optimal conditions, spiked experiments in sinonovacula, mussel, and clam at 10.0-100.0 μg/kg concentrations showed excellent recoveries ranging from 70% to 120% for all analytes with the relative standard deviations of10%. The developed method showed good linearity with the correlation coefficient above 0.9980, and the limits of quantification were in the range of 0.01-9.02 μg/kg. The developed QuEChERS procedure combined with GC-MS/MS was successfully applied to 84 PCBs and OCPs residues detection in shellfish samples.

Molecularly imprinted silica layers appended to quantum dots (MIP-QDs) with customized selective artificial recognition sites were fabricated in this study by optimizing the ratio of the functional monomer to the template. Scanning electron microscopy, transmission electron microscopy, Brunauer–emmett–teller, Fourier transform infrared spectroscopy, and selectivity assay analyses were also performed. Results demonstrated that the selective fluorescence quenching properties of MIP-QDs toward cypermethrin (CYP) are due to strong interactions between these molecules. An enzyme-linked immunosorbent assay (ELISA)-like method based on the MIP-QDs was established under optimal conditions. The fluorescence quenching observed from this method showed a linear relationship with CYP concentration over the range of 0.05–60.0 mg/kg with a correlation coefficient of 0.9838. Good recovery (82.7–92.4%) and a relative standard deviation of less than 10.1% were obtained from fish samples spiked with three levels of CYP. This method also demonstrated a low detection limit of 1.2 μg/kg. The ELISA-like method based on MIP-QDs can be successfully employed to detect residual of CYP in fish samples.

Molecularly imprinted polymers (MIPs) are attracting substantial interest as artificial plastic antibodies because of their biometric capability for targeting small molecules. In this study, molecularly imprinted silica material-coated quantum dots (MIS-QDs) with selective recognition capability to okadaic acid (OA) were developed and characterized. The synthesized MIS-QDs with specific imprinting cavities exhibited excellent recognition capability similar to those of biological antibodies and high fluorescence (FL) quenching selectivity for OA. Furthermore, the MIS-QDs with unsaturated bonds were immobilized onto the surface of 96-well microplates by cold plasma-induced grafting. A novel direct competitive microplate assay strategy was then proposed. The FL quenching properties of the developed microplate assay showed an excellent linear relationship with OA in the range of 10.0-100.0 μg/kg with a correlation coefficient of 0.9961. The limit of detection for OA was 0.25 μg/kg in the shellfish samples. The mean quantitative recoveries were 92.5%-101.0% and 92.9%-101.3%, with relative standard deviations of7.7% and 7.6% for pure solvents and purified shellfish samples, respectively. The established microplate assay strategy can be used as a rapid and high-throughput method for analyzing OA marine toxins in biological samples.

In order to understand the current status of macrobenthos in intertidal zone of Yushan Islands, macrobenthos samples were collected from 5 sections in the intertidal zone in four seasons from March 2009 to January 2010, with the density, biomass, secondary productivity, and P/B value of the macrobenthos investigated by using Brey's empirical formula. The mean density of the marobenthos was 1419.5 ind x m(-2), mean biomass in ash free dry mass (AFDM) was 565.53 g x m(-2), mean annual secondary productivity was 285.58 g x m(-2) x a(-1) (AFDM), and mean annual P/B value was 0.51. The secondary productivity was mainly affected by mollusca and gastropda, with five critical species Septifer virgatus, Modiolus modiolus, Serpulorbis imbricata, Tetraclita japonica, and T. squamosa contributed 84.0% of the total. The P/B value in the study area was lower than that in other sea areas, showing that the generation turnover rate of the macrobenthos in the intertidal zone of Yushan Islands was slower, and the community structure was more stable.

In order to understand the community pattern and biodiversity of macrobenthic fauna in Xiangshan Bay, an eight cruises survey was made at thirteen stations of the Bay from July 2006 to August 2007, with the dominant species composition, richness, biomass, secondary productivity, and P/B value of macrobenthic fauna investigated, and the species diversity of the macrobenthic fauna analyzed. A total of 123 macrobenthos species were recorded, including 48 species Mollusc, 33 species Crustacea, 12 species fish, 12 species annelid polychaete, 8 species echinoderms, and some coelenterates and nematodes. The dominant species were more concentrated, and the dominance index was higher. The average secondary productivity of the macrobenthic fauna was 16.70 g x m(-2) x a(-1), and the average P/B value was 0.60. There existed distinct variations (P0.01) in the species richness index (d), evenness index (J), Simpson's diversity index (D), and Shannon diversity index (H) among different survey stations, and distinct variations (P0.01) in the indices except evenness index (J) between years.