[Wastewater Quantity and Quality Fluctuation Characteristics of Typical Area of Hybrid Sewage System].

The inflow and infiltration problems cause large fluctuation in wastewater quantity and quality in hybrid sewage system. This seriously challenges the operation and management of sewage system. A multi-point on-line simultaneous monitoring system was established in a typical hybrid sewage system.

[Sensing of Cu²⁺ Based on Fenton Reaction and Unmodified Gold Nanoparticles].

Heavy metal pollution has received great attentions in recent years. The traditional methods for heavy metal detection rely on the expensive laboratory instruments and need time-consuming preparation steps; therefore, it is urgent to develop quick and highly sensitive new technologies for heavy metal detection. The colorimetric method based on the gold nanoparticles (AuNPs) features with simple operation, high sensitivity and low cost, therefore, enabling it widely concerned and used in the environmental monitoring, food safety and chemical and biological sensing fields.

Portable optical aptasensor for rapid detection of mycotoxin with a reversible ligand-grafted biosensing surface.

As food safety is gaining prominence as a global issue, the demand for developing rapid, simple, on-site, accurate and low-cost biosensor technologies will continue to grow. This study demonstrates an evanescent wave optical aptasensor with a reversible ligand-grafted biosensing surface for rapid, sensitive and highly selective detection of ochratoxin A (OTA) in food. In this system, the OTA molecules were covalently immobilized onto the surface of an optical fiber using glutaraldehyde and ethylenediamine as space linkers.

[Applicability of bisphenol A detection by a planar waveguide fluorescent biosensor].

As a kind of environmental endocrine disruptors, bisphenol A received a wide attention around the world. The planar waveguide fluorescent biosensor can rapidly and sensitively detect traceable bisphenol A in water samples. Under the optimized test conditions, the typical calibration curve for BPA determination by the biosensor showed a detection limit of (0.

Portable and reusable optofluidics-based biosensing platform for ultrasensitive detection of sulfadimidine in dairy products.

Sulfadimidine (SM2) is a highly toxic and ubiquitous pollutant which requires rapid, sensitive and portable detection method for environmental and food monitoring. Herein, the use for the detection of SM2 of a portable optofluidics-based biosensing platform, which was used for the accurate detection of bisphenol A, atrazine and melamine, is reported for the first time. The proposed compact biosensing system combines the advantages of an evanescent wave immunosensor and microfluidic technology.

[Numerical simulation and operation optimization of biological filter].

BioWin software and two sensitivity analysis methods were used to simulate the Denitrification Biological Filter (DNBF) + Biological Aerated Filter (BAF) process in Yuandang Wastewater Treatment Plant. Based on the BioWin model of DNBF + BAF process, the operation data of September 2013 were used for sensitivity analysis and model calibration, and the operation data of October 2013 were used for model validation. The results indicated that the calibrated model could accurately simulate practical DNBF + BAF processes, and the most sensitive parameters were the parameters related to biofilm, OHOs and aeration.

Label-free detection of kanamycin based on a G-quadruplex DNA aptamer-based fluorescent intercalator displacement assay.

This work was the first to report that the kanamycin-binding DNA aptamer (5'-TGG GGG TTG AGG CTA AGC CGA-3') can form stable parallel G-quadruplex DNA (G4-DNA) structures by themselves and that this phenomenon can be verified by nondenaturing polyacrylamide gel electrophoresis and circular dichroism spectroscopy. Based on these findings, we developed a novel label-free strategy for kanamycin detection based on the G4-DNA aptamer-based fluorescent intercalator displacement assay with thiazole orange (TO) as the fluorescence probe. In the proposed strategy, TO became strongly fluorescent upon binding to kanamycin-binding G4-DNA.

A portable DNAzyme-based optical biosensor for highly sensitive and selective detection of lead (II) in water sample.

A portable, rapid and cost-effective DNAzyme based sensor for lead ions detection in water samples has been developed using an optical fiber sensor platform. The presence of Pb(2+) cleaves the DNAzymes and releases the fluorescent labeled fragments, which further hybridize with the complementary strands immobilized on the optic fiber sensor surface. Subsequent fluorescent signals of the hybridized fluorescent labeled fragment provides quantitative information on the concentrations of Pb(2+) with a dynamic range from 2-75 nM with a detection limit of 1.

Aggregation behavior of engineered nanoparticles and their impact on activated sludge in wastewater treatment.

The ever-increasing daily use of engineered nanoparticles will lead to heightened levels of these materials in the environment. These nanomaterials will eventually go into the wastewater treatment plant (WWTP), therefore, resulting into a pressing need for information on their aggregation behavior and kinetics in the wastewater aqueous matrix. In this work, we dispersed two different metal oxide nanoparticles (ZnO and TiO2) into the influent of two different WWTPs.

[Immunosensor for rapid detection of 1,3-dinitrobenzene].

An immunosensor for the rapid detection of 1,3-dinitrobenzene was developed based on an evanescent wave all-fiber biosensing platform with the detection limits of 0.054 mg x L(-1), and the detection cycle was less than 10 min. Hapten-carrier conjugates NB-OVA were synthesized by mixing 4-nitrohippuric acid and OVA activated by EDC, and then the conjugates were immobilized onto the silane layer on the probe with a heterobifunctional crosslinker.

A portable optic fiber aptasensor for sensitive, specific and rapid detection of bisphenol-A in water samples.

Bisphenol A (BPA) is a known endocrine disruptor and one of the most serious environmental contaminants, often present at low levels in various water sources. Therefore, it is very important and necessary to develop a fast, cost-effective, sensitive, and selective method for on-site detection of BPA. Herein, we developed a portable, evanescent, wave fiber-optic aptasensor for rapid, on-site detection of BPA with high sensitivity and selectivity.

Single cell growth rate and morphological dynamics revealing an "opportunistic" persistence.

Bacteria persistence is a well-known phenomenon, where a small fraction of cells in an isogenic population are able to survive high doses of antibiotic treatment. Since the persistence is often associated with single cell behaviour, the ability to study the dynamic response of individual cells to antibiotics is critical. In this work, we developed a gradient microfluidic system that enables long-term tracking of single cell morphology under a wide range of inhibitor concentrations.

A reusable evanescent wave immunosensor for highly sensitive detection of bisphenol A in water samples.

This paper proposed a compact and portable planar waveguide evanescent wave immunosensor (EWI) for highly sensitive detection of BPA. The incident light is coupled into the planar waveguide chip via a beveled angle through undergoing total internal reflection, where the evanescent wave field forms and excites the binding fluorophore-tagged antibodies on the chip surface. Typical calibration curves obtained for BPA has detection limits of 0.

Microsensor determination of multiple microbial processes in an oxygen-based membrane aerated biofilm.

Microsensor techniques were used to investigate in situ the simultaneous occurrence of sulfate reduction and nitrogen removal in a membrane aerated biofilm reactor. H2S, O2, pH, ORP, NH4(+) and NO3(-) microsensors were fabricated and used to measure the profiles inside the membrane aerated biofilm. Production and consumption rates of H2S, O2, NH4(+) and NO3(-) were estimated using corresponding concentration profiles.

Gradient microfluidics enables rapid bacterial growth inhibition testing.

Bacterial growth inhibition tests have become a standard measure of the adverse effects of inhibitors for a wide range of applications, such as toxicity testing in the medical and environmental sciences. However, conventional well-plate formats for these tests are laborious and provide limited information (often being restricted to an end-point assay). In this study, we have developed a microfluidic system that enables fast quantification of the effect of an inhibitor on bacteria growth and survival, within a single experiment.

Automated online optical biosensing system for continuous real-time determination of microcystin-LR with high sensitivity and specificity: early warning for cyanotoxin risk in drinking water sources.

The accelerated eutrophication of surface water sources and climate change have led to an annual occurrence of cyanobacterial blooms in many drinking water resources. To minimize the health risks to the public, cyanotoxin detection methods that are rapid, sensitive, real time, and high frequency must be established. In this study, an innovative automated online optical biosensing system (AOBS) was developed for the rapid detection and early warning of microcystin-LR (MC-LR), one of the most toxic cyanotoxins and most frequently detected in environmental water.

[Measurement and analysis of micropore aeration system's oxygenating ability under operation condition in waste water treatment plant].

Using the aeration pool in the fourth-stage at Wuxi Lucun Waste Water Treatment Plant (WWTP) as experimental setup, off-gas method was selected to measure the oxygenating ability parameters of micropore aerators in a real WWTP operating condition and these values were compared with those in fresh water to evaluate the performance of the micropore aerators. Results showed that the micropore aerators which were distributed in different galleries of the aeration pool had significantly different oxygenating abilities under operation condition. The oxygenating ability of the micropore aerators distributed in the same gallery changed slightly during one day.

[Matrix effect and control of immunoassay for environmental samples].

Immunoassay provides very specific, highly sensitive, rapid, and cost-effective analyses for a variety of environmental contaminants. Since the immunoassay detects the environmental samples without pre-treatment, the interferences caused by various matrixes of environmental samples are a major problem, which can greatly affect the detection results. In this paper, based on the enzyme-linked immunosorbent assay (ELISA) for detection of Microcystin-LR (MC-LR), the effect of many kinds of matrixes on ELISA was systematically analyzed, and the corresponding method to control or eliminate the disbennifit effect was proposed.

[Effect of polymeric aluminum-iron on EPS and bio-flocculation in A2/O system].

Polymeric aluminum-iron (PAFC) was added at the end of aeration tank to enhance phosphorus removal, so that the phosphorus concentration in the effluent could meet the calss A standard in municipal sewage treatment plant pollutant discharge standard (GB 18918-2002). The characteristics of extracellular polymer substances (EPS) and bio-flocculation for the activated sludge in the A2/O system were analyzed in the experiment. The results showed that, the gross of EPS varied little with the increase in PAFC dosage, while, the ratio of albumen to polysaccharide declined from 3.

Aptamer-based optical biosensor for rapid and sensitive detection of 17β-estradiol in water samples.

Required routine monitoring of endocrine disrupting compounds (EDCs) in water samples, as posed by EPA Unregulated Contaminant Regulation (UCMR3), demands for cost-effective, reliable and sensitive EDC detection methods. This study reports a reusable evanescent wave aptamer-based biosensor for rapid, sensitive and highly selective detection of 17β-estradiol, an EDC that is frequently detected in environmental water samples. In this system, the capture molecular, β-estradiol 6-(O-carboxy-methyl)oxime-BSA, was covalently immobilized onto the optical fiber sensor surface.

[Evaluation of pathogen disinfection efficacy by chlorine and monochloramine disinfection based on quantitative PCR combined with propidium monoazide (PMA-qPCR)].

A novel detection method of quantitative PCR combined with a DNA intercalating dye propidium monoazide (PMA-qPCR) was developed and then applied to analyze inactivation efficacy of chlorine and monochloramine on E. coli as a representative organism. The results shows that PMA removed 99.

[Start-up of a thermophilic anaerobic sludge digester].

Anaerobic digestion is one of the most widely-used technologies of the sludge reduction and stabilization, in which thermophilic digestion has advantage of fast stabilization. But it is lack of operation experience in China. Thus start-up of a thermophilic anaerobic sludge digester treating excess activated sludge was investigated.

[Effect of PCP on the living cell content and distribution in biofilms].

The phospholipids method for the determination of the living cell content in the biofilm was established to study the wastewater biofilm. With the micro-slicing technology, the biofilm was divided into 150 microm-layer for the phospholipids analysis. Results showed the phospholipids were approximately normal distribution along the biofilm depth without no addition of pentachlorophenol (PCP).

Development of a combined immunomagnetic separation and quantitative reverse transcription-PCR assay for sensitive detection of infectious rotavirus in water samples.

A quantitative and rapid detection method for rotavirus in water samples was developed using immunomagnetic separation combined with quantitative reverse transcription-polymerase chain reaction (IMS-RT-qPCR). Magnetic beads coated with antibodies against representative group A rotavirus were used to capture and purify intact rotavirus particles in both artificial and real environmental water sample matrix. Compared to extracting RNA using commercial kits and RT-qPCR assay, the developed IMS-RT-qPCR method increased the detection sensitivity by about one order of magnitude when applied in clean water, with a detection limit of 3.

Temporal and spatial inhibitory effects of zinc and copper on wastewater biofilms from oxygen concentration profiles determined by microelectrodes.

To understand the temporal and spatial toxic effect of heavy metals on the microbial activities of biofilms, microelectrodes were used to measure the inhibitory oxygen (O(2)) concentration profiles resulted from the effects of zinc (Zn(2+)) and copper (Cu(2+)). Using the O(2) microprofiles as bases, the spatial distributions of net specific O(2) respiration were determined in biofilms with and without treatment of 5 mg/L Zn(2+) or 1 mg/L Cu(2+). Results show that microbial activities were inhibited only in the outer layer (∼400 μm) of the biofilms and bacteria present in the deeper sections of the biofilms became even more active.