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A miniaturized device for simultaneous measurement of glucose and lactate levels was produced by means of photopatterning of enzyme-containing photosensitive membrane precursors. This device shows no cross-talk and a lifetime for both the glucose and the lactate sensors of more than 2 weeks when continuously operated in undiluted bovine serum. Linear response ranges of up to 40 mM for glucose and 25 mM for L-lactate, in combination with 95% response times of 0.98 with respect to laboratory techniques. Subcutaneous measurements of glucose levels in pigs were close to the corresponding blood levels obtained without in vivo calibration.

Bioprocess development and fermentation control would benefit from a timely knowledge of metabolic parameters, e.g., glucose, glutamine, and lactate concentration etc., enabling adequate intervention, maximizing product yield, and providing process analytical tools for reliable and traceable bioprocessing in the context of process analytical technology. A polymer laminate technology based microsytem comprising integrated pre-calibrated electrochemical biosensors for the simultaneous monitoring of lactate, glucose, glutamine, and glutamate in a 0.15-μL flow-through cell for process monitoring and control is presented. Flexible manufacturing technologies used for these devices allow a cost effective customization of them. [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]

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., (Copyright © 2018 Elsevier B.V. All rights reserved.)

The development of integrated, fast and affordable platforms for pathogen detection is an emerging area where a multidisciplinary approach is necessary for designing microsystems employing miniaturized devices; these new technologies promise a significant advancement of the current state of analytical testing leading to improved healthcare. In this work, the development of a lab-on-chip microsystem platform for the genetic analysis of Salmonella in milk samples is presented. The heart of the platform is an acoustic detection biochip, integrated with a microfluidic module. This detection platform is combined with a micro-processor, which, alongside with magnetic beads technology and a DNA micro-amplification module, are responsible for performing sample pre-treatment, bacteria lysis, nucleic acid purification and amplification. Automated, multiscale manipulation of fluids in complex microchannel networks is combined with novel sensing principles developed by some of the partners. This system is expected to have a significant impact in food-pathogen detection by providing for the first time an integrated detection test for Salmonella screening in a very short time. Finally, thanks to the low cost and compact technologies involved, the proposed set-up is expected to provide a competitive analytical platform for direct application in field settings.

The hypoxic areas of solid cancers represent a negative prognostic factor irrespective of which treatment modality is chosen for the patient. Still, after almost 80 years of focus on the problems created by hypoxia in solid tumours, we still largely lack methods to deal efficiently with these treatment-resistant cells. The consequences of this lack may be serious for many patients: Not only is there a negative correlation between the hypoxic fraction in tumours and the outcome of radiotherapy as well as many types of chemotherapy, a correlation has been shown between the hypoxic fraction in tumours and cancer metastasis. Thus, on a fundamental basis the great variety of problems related to hypoxia in cancer treatment has to do with the broad range of functions oxygen (and lack of oxygen) have in cells and tissues. Therefore, activation-deactivation of oxygen-regulated cascades related to metabolism or external signalling are important areas for the identification of mechanisms as potential targets for hypoxia-specific treatment. Also the chemistry related to reactive oxygen radicals (ROS) and the biological handling of ROS are part of the problem complex. The problem is further complicated by the great variety in oxygen concentrations found in tissues. For tumour hypoxia to be used as a marker for individualisation of treatment there is a need for non-invasive methods to measure oxygen routinely in patient tumours. A large-scale collaborative EU-financed project 2009-2014 denoted METOXIA has studied all the mentioned aspects of hypoxia with the aim of selecting potential targets for new hypoxia-specific therapy and develop the first stage of tests for this therapy. A new non-invasive PET-imaging method based on the 2-nitroimidazole [(18)F]-HX4 was found to be promising in a clinical trial on NSCLC patients. New preclinical models for testing of the metastatic potential of cells were developed, both in vitro (2D as well as 3D models) and in mice (orthotopic grafting). Low density quantitative real-time polymerase chain reaction (qPCR)-based assays were developed measuring multiple hypoxia-responsive markers in parallel to identify tumour hypoxia-related patterns of gene expression. As possible targets for new therapy two main regulatory cascades were prioritised: The hypoxia-inducible-factor (HIF)-regulated cascades operating at moderate to weak hypoxia (<1% O(2)), and the unfolded protein response (UPR) activated by endoplasmatic reticulum (ER) stress and operating at more severe hypoxia (<0.2%). The prioritised targets were the HIF-regulated proteins carbonic anhydrase IX (CAIX), the lactate transporter MCT4 and the PERK/eIF2α/ATF4-arm of the UPR. The METOXIA project has developed patented compounds targeting CAIX with a preclinical documented effect. Since hypoxia-specific treatments alone are not curative they will have to be combined with traditional anti-cancer therapy to eradicate the aerobic cancer cell population as well.

Arrays of monolithically integrated Mach-Zehnder interferometers were fabricated by standard silicon technology and applied to the label-free real-time monitoring of biomolecular interactions. Chips accommodating 10 MZIs were functionalized with recognition biomolecules and encapsulated in wafer scale. Detection is based on Frequency-Resolved Mach-Zehnder Interferometry, a new concept that takes advantage of the broad-band input spectrum by monitoring the changes for every input frequency. The sensitivity of the device in terms of refractive index changes (Δn) was calculated using isopropanol/water solutions. A detection limit of Δn = 4 × 10(-6) was calculated. The bioanalytical capabilities of the device there demonstrated through model binding assays (biotin/streptavidin) as well as the detection of total prostate specific antigen in serum samples using devices coated with antigen-specific monoclonal antibody. Detection limits at the pM range were determined.

The application of fully monolithically-integrated Mach-Zehnder interferometer arrays fabricated by standard silicon technology to the label-free detection of analytes is introduced. Detection with the presented biosensor is based on a novel concept, the Frequency-Resolved Mach-Zehnder Interferometry (FR-MZI). In addition, a smart encapsulation based on an appropriately designed microfluidic system and performed at the wafer scale scheme for the easy delivery of the samples to be analyzed is demonstrated. Testing of the FR-MZI biosensors with model binding assays demonstrated the detection of streptavidin binding to immobilized biotin at concentrations in the sub nM range. This is the first experimental demonstration of the FR-MZI concept as well as the first demonstration of a monolithically fully-integrated MZI biosensor.

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 microm thick seal, and electrical interconnection lines. The flow device has a total internal volume of 2.1 or 6 microl 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.