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Low volume multi-parameter LoCs for the monitoring of metabolic parameters and flow rate with integrated micro-pumps intended for single-use applications are enabled by cost-effective polymer laminate-based manufacture with wafer-level μFluidics packaging. Integration of flow rate sensing and pumping to these biosensors based BIOMEMS is enabling for the reliable biotechnology and medical application. [ABSTRACT FROM AUTHOR]

For simultaneous measurement of glucose, lactate, glutamine, and glutamate a biosensor array is implemented in a micro flow-system thus giving a microsystem. The microsystem consists of a glass chip with the integrated biosensor array and a bottom part, which comprises a gold counter electrode, a 300 μm thick seal, and electrical interconnection lines. The flow device has a total internal volume of 2.1 or 6 μl when integrated with a mixer on chip. The biosensors with no crosstalking and high long term stability were produced by modifying the electrochemical transducers and utilizing photopatternable enzyme membranes. The use of appropriate miniaturization technology leads to mass producable devices for in vivo and ex vivo applications in whole blood and fermentation broth. Due to a novel glutaminase with an activity optimum in the neutral pH range direct and simultaneous monitoring of glutamine together with glucose, lactate, and glutamate could be performed. [Copyright &y& Elsevier]

[Display omitted] • Ten MZIs, optical sources, spectral analyzers, and photodiode arrays on a single chip. • Portable reader based on all-in-one monolithic photonic chips. • Multiplexed determination of 3 allergens in industry rinsing water samples in 10 min. • Dual mycotoxins determination in beer samples within 15 min. Silicon chips that monolithically integrate ten Mach-Zehnder interferometers (MZIs), their respective broad-band optical sources, and spectral analyzers, as well as photodiode arrays that record the spectrally-resolved output signals of the ten MZIs, are exploited for the multiplexed immunochemical determination of allergens and mycotoxins. The monolithically integrated light sources emit light in the visible/infrared spectrum (530–950 nm), and thus the detection based on broad-band Mach-Zehnder interferometry provided information about changes in the refractive index on the transducer surface due to binding reactions across the entire spectrum, surpassing the limitations of traditional monochromatic interferometry. The assays were run using a portable automated reader incorporating the chip fluidic and electronic interfacing, a micropump for continuous fluid delivery, and control electronics combined with a software for real-time signal monitoring. The photonic chips and portable reader were applied for allergen detection in dairy industry rinsing waters and mycotoxin detection in beer samples. All analytes were determined through competitive immunoassays. For the multiplexed detection of three allergens (bovine κ-casein, peanut protein, and gliadin), the respective proteins were immobilized onto the sensing windows of different MZIs on a single chip. For the detection of mycotoxins (fumonisin B1 and deoxynivalenol), the respective mycotoxin-protein conjugates were employed. In all cases, the reaction with mixtures of calibrators/samples and analyte-specific antibodies was followed by a reaction with appropriate secondary antibodies to enhance the signal and reduce the assay duration. The allergen assays were completed in 10 min with detection limits of 0.01, 0.25, and 0.05 μg/mL for κ-casein, peanut protein, and gliadin, respectively. The mycotoxin assays took 15 min with detection limits of 2.0 and 10 ng/mL for fumonisin B1 and deoxynivalenol, respectively, in beer samples. The results demonstrate the potential of the developed solution for the rapid and sensitive on-site multiplexed detection of targeted analytes. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Fabrication, and evaluation of an integrated Lab-on-Chip platform. • Bacteria capture, thermal lysis, DNA purification, and isothermal DNA amplification on chip. • Pathogen screening in milk samples for cell lysates corresponding to <500 cells. Abstract Strict regulations govern food safety as the latter is of extremely high importance and a major public issue, while it is demanding in respect of analytical effort. The duration of common food analysis practices is typically 2–5 days. Microfluidics can reduce labor and analysis time to a few hours, proving its beneficial use and rendering the response of food industry as well as public safety agents faster. The aim of the present work is the fabrication and evaluation of a modular integrated Lab-on-Chip platform for sample preparation, accommodating bacteria capture, thermal lysis, DNA purification, and isothermal DNA amplification, addressing pathogen screening in milk samples for cell lysates corresponding to <500 cells. We note that individual modules have been tested to work down to 10 cells. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Optical immunosensor for label-free detection of AFB1, FB1and DON in beer. • The three mycotoxins are determined following a competitive immunoassay format. • The multiplexed assay duration is 12 min. • The sensor can determine the three mycotoxins in different beer types. Abstract A label-free optical biosensor for the fast simultaneous determination of three mycotoxins, aflatoxin B 1 (AFB 1), fumonisin B 1 (FB 1) and deoxynivalenol (DON), in beer samples is presented. The biosensor is based on an array of ten Mach-Zehnder interferometers (MZIs) monolithically integrated along with their respective broad-band silicon light sources onto a single chip. Multi-analyte determination is accomplished by functionalizing the sensing arms of individual MZIs with mycotoxin-protein conjugates. Assay is performed by pumping over the chip mixtures of calibrators or samples with a mixture of specific monoclonal antibodies, followed by reaction with a secondary anti-mouse IgG antibody. Reactions are monitored in real-time by continuously recording the MZI output spectra, which are then subjected to Discrete Fourier Transform to convert spectrum shifts to phase shifts. The detection limits achieved for AFB 1 , FB 1 and DON were 0.8, 5.6 and 24 ng/ml, respectively, while the assay duration was 12 min. Recovery values ranging from 85 to 115% were determined in beer samples spiked with known concentrations of the three mycotoxins. In addition, beers of different types and origin were analysed with the biosensor developed and the results were compared with those provided by established laboratory methods, further supporting the accuracy of the proposed device. [ABSTRACT FROM AUTHOR]