In nearly all papers concerning enzyme-nanoparticle based bioelectronic devices, it is stated that the presence of nanoparticles on electrode surfaces per se enhances bioelectrocatalysis, although the reasons for that enhancement are often unclear. Here, we report detailed experimental evidence that neither an overpotential of bioelectrocatalysis, nor direct electron transfer and bioelectrocatalytic reaction rates for an adsorbed enzyme depend on the size of nanoparticles within the range of 20-80 nm, i.e. for nanoparticles that are considerably larger than the enzyme molecules.Bioelectronics is a rapidly progressing interdisciplinary research eld 1 that aims to integrate biomaterials and electronic elements into functional devices which, among many other applications, can be used in high-tech, environmental, pharmaceutical and biomedical industries for sensing and power-generation purposes. High-performance direct electron transfer (DET)-based bioelectrocatalytic reactions at low overpotentials are needed to design sensitive, selective, and efficient third-generation (DET-based) bioelectronic devices, e.g. biosensors 2,3 and biofuel cells, 4,5 since third-generation bioelectronics are simple, non-toxic, and potentially miniaturisable down to nm scale. Nanostructuring electrode surfaces for enzyme-based bioelectronics is important because, in most cases, "planar" biodevices, i.e. designed without articial nanodecoration of electrodes, show very little or no electron transfer (ET) between immobilised redox enzymes and unmodied surfaces. The commonly offered explanation for "enzyme nanowiring" is an appropriate orientation of proteins on nanomaterials for ET reactions. Facile and effective bioelectrocatalysis has been shown in many papers, where different mono-and multi-centre redox enzymes, such as horseradish peroxidase, 6 glucose oxidase, 7-10 superoxide dismutase, 11 and cellobiose dehydrogenase, 12 with blue multicopper oxidases (MCOs), 13-18 respectively, are immobilised on different nanomaterials, e.g. metal and carbon nanoparticles (NPs) and nanotubes, graphene, nanoporous materials, etc. As a major proof for the enhancement of bioelectrocatalytic reactions, large bioelectrocatalytic currents that originate from nanostructured electrodes modied with oxidoreductases are usually presented. However, it should be emphasised that electrocatalysis is not actually related to the current increase, but should result in the decrease of an overpotential, which is quite rarely addressed in the case of bioelectrocatalytic reactions. Moreover, even for a particular enzyme, e.g. Trametes hirsuta laccase (ThLc), and a particular material, e.g. gold (Au), contradictory situations for different nanostructures can be found in the literature: the use of gold NPs (AuNPs) and nanoporous Au was shown to facilitate the DET-based bioelectrocatalytic reduction of oxygen (O 2 ), 13,18 whereas Aumodied nano-/microstructured silicon chips with the immobilised enzyme displayed very limited DET-based activity. 19Furthermore, two op...

h i g h l i g h t sTransparent and flexible enzymatic fuel cells were fabricated and characterised. The glucose/oxygen utilising devices were nanostructured, membrane-less and mediator-free. Nanoimprint lithography was used for nanostructuring of polymer based electrodes. Nanostructured electrodes were metallised and biomodified. This type of biodevice could potentially be used in smart electronic contact lenses. Here we detail transparent, flexible, nanostructured, membrane-less and mediator-free glucose/oxygen enzymatic fuel cells, which can be reproducibly fabricated with industrial scale throughput. The electrodes were built on a biocompatible flexible polymer, while nanoimprint lithography was used for their nanostructuring. The electrodes were covered with gold, their surfaces were visualised using scanning electron and atomic force microscopies, and they were also studied spectrophotometrically and electrochemically. The enzymatic fuel cells were fabricated following our previous reports on membrane-less and mediator-free biodevices in which cellobiose dehydrogenase and bilirubin oxidase were used as anodic and cathodic biocatalysts, respectively. The following average characteristics of transparent and flexible biodevices operating in glucose and chloride containing neutral buffers were registered: 0.63 V open-circuit voltage, and 0.6 mW cm À2 maximal power density at a cell voltage of 0.35 V. A transparent and flexible enzymatic fuel cell could still deliver at least 0.5 mW cm À2 after 12 h of continuous operation.Thus, such biodevices can potentially be used as self-powered biosensors or electric power sources for smart electronic contact lenses.

Background & Aims: A number of factors have been identified that influence the yield of screeningcolonoscopy. The perceived tolerability of bowel preparation has not been studied as a predictor of quality outcomes in colonoscopy. We aimed to characterize the association between patient-perceived tolerability of bowel preparation and polyp detection during colonoscopy.Methods: We performed a cross-sectional cohort study of 413 consecutive adult patients presenting foroutpatient colonoscopy at two outpatient endoscopy centers at our institution. We developed a standardized questionnaire to assess the patient's experience with bowel preparation. Bowel preparation quality was measured using the validated Ottawa scale and colonoscopic findings were recorded for each patient. The primary outcome was polyp detection and the secondary outcome was the quality of bowel preparation.Results: Patient-reported clarity of effluent during bowel preparation correlated poorly with Ottawa score during colonoscopy, k=0.15. Female gender was an independent risk factor for a poorly tolerated bowel prep (OR 3.93, 95% CI 2.30 - 6.72, p<0.001). Report of a poorly tolerated bowel prep was independently associated with the primary outcome, polyp detection (OR 0.39, 95% CI 0.18 - 0.84, p=0.02) and also with the secondary outcome, lower quality bowel preparation (OR 2.39, 95% CI 1.17 - 4.9, p=0.02).Conclusions: A patient-perceived negative experience with bowel preparation independently predicted both a lower quality bowel preparation and a lower rate of polyp of detection. Assessment of the tolerability of bowel preparation before colonoscopy may be a clinically useful predictor of quality outcomes during colonoscopy.