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Abstract: Ochratoxin A (OTA), a mycotoxin which occurs naturally in a variety of crops (e.g. cereals, grapes), can contaminate feedstock and beverages derived from these crops (e.g. wine and beer) . OTA detection is critical for food safety since exposure through consumption is related to potential health risks, namely cancer . Food and beverages commercialized in Europe must follow the European Commission regulations for the amount of OTA allowed.In this work, OTA detection was developed and performed based on indirect competitive enzyme linked immunosorbent assays (icELISA) perfomed inside polydimethylsiloxane microchannels. The microfluidic icELISA is integrated with hydrogenated amorphous silicon photodiodes microfabricated on a glass substrate for a fast, reliable, and portable OTA detection and quantification system. [Copyright &y& Elsevier]

Microbial interactions play an important role in initial cell adhesion and the endurance of biofilm toward disinfectant stresses. The present study aimed to evaluate the effect of microbial interactions on biofilm formation and the disinfecting activity of an innovative photocatalytic surfactant based on TiO 2 nanoparticles. Listeria monocytogenes , Salmonella Enteritidis, Escherichia coli , Leuconostoc spp., Latilactobacillus sakei , Serratia liquefaciens , Serratia proteomaculans , Citrobacter freundii , Hafnia alvei , Proteus vulgaris , Pseudomonas fragi , and Brochothrix thermosphacta left to form mono- or dual-species biofilms on stainless steel (SS) coupons. The effectiveness of the photocatalytic disinfectant after 2 h of exposure under UV light on biofilm decontamination was evaluated. The effect of one parameter i.e., exposure to UV or disinfectant, was also determined. According to the obtained results, the microbial load of a mature biofilm depended on the different species or dual species that had adhered to the surface, while the presence of other species could affect the biofilm population of a specific microbe ( p < 0.05). The disinfectant strengthened the antimicrobial activity of UV, as, in most cases, the remaining biofilm population was below the detection limit of the method. Moreover, the presence of more than one species affected the resistance of the biofilm cells to UV and the disinfectant ( p < 0.05). In conclusion, this study confirms that microbial interactions affected biofilm formation and decontamination, and it demonstrates the effectiveness of the surfactant with the photocatalytic TiO 2 agent, suggesting that it could be an alternative agent with which to disinfect contaminated surfaces.

Biomolecular detection systems based on microfluidics are often called lab-on-chip systems. To fully benefit from the miniaturization resulting from microfluidics, one aims to develop 'from sample-to-answer' analytical systems, in which the input is a raw or minimally processed biological, food/feed or environmental sample and the output is a quantitative or qualitative assessment of one or more analytes of interest. In general, such systems will require the integration of several steps or operations to perform their function. This review will discuss these stages of operation, including fluidic handling, which assures that the desired fluid arrives at a specific location at the right time and under the appropriate flow conditions; molecular recognition, which allows the capture of specific analytes at precise locations on the chip; transduction of the molecular recognition event into a measurable signal; sample preparation upstream from analyte capture; and signal amplification procedures to increase sensitivity. Seamless integration of the different stages is required to achieve a point-of-care/point-of-use lab-on-chip device that allows analyte detection at the relevant sensitivity ranges, with a competitive analysis time and cost., (© 2016 The Author(s). Published by Portland Press Limited on behalf of the Biochemical Society.)

Positive urine cultures are common and often asymptomatic in the male spinal injured patient performing self clean intermittent catheterisation. It is possible that the positive urine cultures result from contamination from the colonised urethra at the time of catheterisation. This contamination could result in true infection of the bladder urine or yield false positive results, explaining the frequently seen asymptomatic cases. In a prospective study positive urine cultures were found on 58 occasions (74%) in 10 asymptomatic patients studied. In 19% of screenings, with positive urine cultures, an identical organism was cultured from the catheter specimen of urine, the perineum and the urethra. The flora of the anterior urethra is strongly correlated to that of the perineum (37.1%), as well as that of the bladder (52.6%). In 4 patients a correlation also existed between the urethra and fingers, and the perineum and fingers. This was associated with an increased incidence of positive urine culture in these patients. Suprapubic aspirates of urine before and after catheterisation cultured the same organisms. However, quantitative culture revealed colony counts that approached a 10-fold increase following catheterisation in one patient. This suggests that catheterisation is at least partially responsible for ascending infection in this group of patients. Catheter specimens were found to be a good representation of the bladder urine, with an 87.5% correlation.