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We demonstrate a platform for implementing quantum walks that overcomes many of the barriers associated with photonic implementations. We use coupled fiber-optic cavities to implement time-bin encoded walks in an integrated system. We show that this platform can achieve very low losses combined with high-fidelity operations, enabling an unprecedented large number of steps in a passive system, as required for scenarios with multiple walkers. Furthermore the platform is reconfigurable, enabling variation of the coin, and readily extends to multidimensional lattices. We demonstrate variation of the coin bias experimentally for three different values. [ABSTRACT FROM AUTHOR]

The electric dipoles of proteins in a biolayer determine their dielectric properties through the polarization density P. Hence, its reproducibility is crucial for applications, particularly in bioelectronics. Biolayers encompassing capturing antibodies covalently bound at a biosensing interface are generally preferred for their assumed higher stability. However, surface physisorption is shown to offer advantages like easily scalable fabrication processes and high stability. The present study investigates the effects of electric-field (EF)-cycling of anti-Immunoglobulin M (anti-IgM) biolayers physisorbed on Au. The impact of EF-cycling on the dielectric, optical, and mechanical properties of anti-IgM biolayer is investigated. A reduction of the dispersion (standard deviation over a set of 31 samples) of the measured P values is observed, while the set median stays almost constant. Hence, physisorption combined with EF cycling, results in a biolayer with highly reproducible bioelectronic properties. Additionally, the study provides important insights into the mechanisms of dielectric rearrangement of dipole moments in capturing biolayers after EF-cycling. Notably, EF-cycling acts as an annealing process, driving the proteins in the biolayer into a statistically more probable and stable conformational state. Understanding these phenomena enhances the knowledge of the properties of physisorbed biolayers and can inform design strategies for bioelectronic devices., (© 2024 The Author(s). Advanced Science published by Wiley‐VCH GmbH.)

Ultrasound-guided local anaesthesia is commonly used in veterinary orthopaedics for horses. This study aimed to assess an in vivo ultrasound technique for the medial branch of the dorsal branch of the cervical spinal nerves (MB-DBCSNs) in horses and compare the performance of clinicians with different experience levels. Ten healthy, skeletally mature horses were examined using radiographic and ultrasound (US) techniques in the cervical area (C3-C7). Four operators with varying experience conducted US examinations using a 10 MHz linear and 6 MHz curvilinear transducer over ten training sessions. The number of cervical nerves visualized was recorded. A chi-square test was used to analyse the impact of training, anatomical location, and operator experience on the identification of facet joints. Operator agreement was evaluated with Cohen's K test. The operators assessed 80 MB-DBCSNs, with radiographs and identified 70 healthy and 10 pathological facet joints. Training significantly improved visualization success, reaching 90% in later sessions. Cranial facet joints (C3-C5) were more frequently visualized (81%) than caudal ones (C5-C7) were (59%). US performance was influenced by the operator's skill, and agreement among operators ranged from slight to fair. Overall, practice improved cervical nerve visualization in vivo , particularly for cranial nerves, but the technique requires a long learning curve because of low levels of operator agreement.

This study aimed to describe an ultrasound-guided technique for implanting catheters for local anesthetic administration into the quadratus lumborum (QL) inter-fascial plane in canine cadavers and assessing the spread along the vertebral bodies (VBs) by computed tomography (CT). Phase 1: eight canine cadavers received one catheter per hemiabdomen, followed by injection of contrast media solution [low volume (L V ) 0.3 mL kg -1 or high volume (H V ) 0.6 mL kg -1 ]. Phase 2: postoperative pain of five dogs was managed by injecting 0.3 mL kg -1 of ropivacaine 0.5% through QL catheters every eight hours, up to 72 h after abdominal surgery. Pain was assessed using the Short Form of the Glasgow Composite Measure Pain Scale, and methadone 0.2 mg kg -1 was administered intravenously when the pain score was ≥6. The number of VBs stained by the contrast solution between the QL and psoas minor muscles was significantly higher in group H V than group L V . The catheter tip was visualized in the retroperitoneal space in 1/16 and 2/10 hemiabdomens in phases 1 and 2, respectively. Rescue analgesia was required in 3/5 dogs during the postoperative period. The QL catheter placement technique appears feasible and may be included in a multimodal analgesic approach for dogs undergoing abdominal surgeries.

Musculoskeletal abnormalities in neonate equids represent a common condition, which includes angular limb deformities, defective carpal/tarsal bone ossification, contracted limb and mandibular/maxillary prognathism. The present case report described the presentation and surgical management of multiple musculoskeletal abnormalities in a mule foal. A newborn mule foal was presented for several musculoskeletal abnormalities, such as angular deviation from the sagittal plane of both carpal joints, hind limb ligament laxity, and severe mandibular prognathism. Surgical management of mandibular prognathism was then treated through the application of a tension orthodontic wire. Postoperatively, there was a significant improvement in the correction of mandibular malocclusion and no further correction was needed. Management of other anomalies was mainly conservative, with stall rest and exercise limitations, with a considerable improvement in the first month of life. Thus, jaw malformations might be observed also in mule foals, and might be associated with multiple congenital abnormalities. Early recognition, appropriate management, and surgical treatment were essential., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier Inc.)

Biosensors have demonstrated versatility across numerous applications; however, their systematic optimization remains a primary obstacle, limiting their widespread adoption as dependable point-of-care tests. Experimental design, a powerful chemometric tool, offers a solution by effectively guiding the development and optimization of ultrasensitive biosensors. This perspective review provides an overview of recent applications of experimental design in the deployment of optical and electrical ultrasensitive biosensors. Various experimental designs, including full factorial, central composite, and mixture designs, are examined as systematic methodologies for optimizing biosensor fabrication, accounting for both individual variable effects and their interactions. Illustrative examples showcasing the optimization of optical and electronic biosensors through design of experiments are presented and critically analyzed. Finally, the future prospects of experimental design in the biosensor community are outlined, highlighting its potential to expedite development and bolster the performance of biosensing devices for point-of-care diagnostics, thereby facilitating their sustainable and reliable integration., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

This work aimed to evaluate the potential of the nanosystems constituted by dopamine (DA) and the antioxidant Citicoline (CIT) co-loaded in solid lipid nanoparticles (SLNs) for intranasal administration in the treatment of Parkinson disease (PD). Such nanosystems, denoted as DA-CIT-SLNs, were designed according to the concept of multifunctional nanomedicine where multiple biological roles are combined into a single nanocarrier and prepared by the melt emulsification method employing the self-emulsifying Gelucire ® 50/13 as lipid matrix. The resulting DA-CIT-SLNs were characterized regarding particle size, surface charge, encapsulation efficiency, morphology, and physical stability. Differential scanning calorimetry, FT-IR, and X ray diffraction studies were carried out to gain information on solid-state features, and in vitro release tests in simulated nasal fluid (SNF) were performed. Monitoring the particle size at two temperatures (4 °C and 37 °C), the size enlargement observed over the time at 37 °C was lower than that observed at 4 °C, even though at higher temperature, color changes occurred, indicative of possible neurotransmitter decomposition. Solid-state studies indicated a reduction in the crystallinity when DA and CIT are co-encapsulated in DA-CIT-SLNs. Interestingly, in vitro release studies in SNF indicated a sustained release of DA. Furthermore, DA-CIT SLNs displayed high cytocompatibility with both human nasal RPMI 2650 and neuronal SH-SY5Y cells. Furthermore, OxyBlot assay demonstrated considerable potential to assess the protective effect of antioxidant agents against oxidative cellular damage. Thus, such protective effect was shown by DA-CIT-SLNs, which constitute a promising formulation for PD application.

The aim of this study was to evaluate whether a constant rate infusion of dexmedetomidine could prolong the analgesic effect of peripheral nerve blocks. Twenty client-owned dogs were enrolled and randomly divided into 2 groups. The DEX group received dexmedetomidine infusion at 1 mcg kg -1  h -1 , and the NaCl group received an equivalent volume infusion of saline. Infusions were started after securing vascular access and continued for 10 min, after which intravenous (IV) methadone at 0.2 mg kg -1 and propofol to effect were administered. All animals were maintained with isoflurane in 70% oxygen. Sciatic, saphenous and obturator nerve blocks were performed using 0.1 mL kg -1 0.5% ropivacaine/block. Intraoperative fentanyl was administered if the heart rate and/or mean arterial pressure (MAP) increased > 15% from the previous measurement, and vasopressors were administered if MAP was ≤ 70 mmHg. Postoperative pain was assessed every hour using the Glasgow Composite Pain Scale (GCPS) until the first rescue analgesia administration. Postoperative rescue analgesia (methadone (0.2 mg kg -1 IV) and carprofen (2 mg kg -1 IV)) was administered if the pain score was higher than 6/24 or 5/20. Duration of analgesia was defined as the time between the nerve block procedure and initial postoperative rescue analgesia. Ambulation, proprioception, and skin sensitivity were evaluated to assess the duration of the motor and sensory block. A Student T and chi-square test were used to compare groups for duration of postoperative analgesia and intraoperative fentanyl and vasopressor use, respectively (p values ≤ 0.5 considered significant). A greater number of dogs in the NaCl group required fentanyl (5/10 p = 0.03) and vasopressors (8/10, p = 0.02) than did those in the DEX group (0/10 and 2/10, respectively). The duration of postoperative analgesia was significantly longer (604 ± 130 min) in the DEX group than in the NaCl group (400 ± 81 min, p = 0.0005).Dexmedetomidine infusion at 1 mcg kg -1  h -1 delays the time to first administration of rescue analgesia and reduces intraoperative analgesic and vasopressor requirements during Tibial Tuberosity Advancement surgery., (© 2024. The Author(s).)

The purpose of this study was to evaluate the quality of recovery from general anesthesia with the administration of two low doses of dexmedetomidine in canine patients. For this blind randomized clinical trial study, 30 dogs undergoing general anesthesia for diagnostic procedures or elective surgery (ovariectomy/castration) were included. The patients were randomly divided into three groups, and at the end of anesthesia, they received a bolus of dexmedetomidine at 1 mcg/kg IV (D1), or a bolus of dexmedetomidine at 0.5 mcg/kg (D0.5), or a bolus of NaCl, in a total of 0.5 mL of solution for all three groups. After administration of the bolus, the anesthetist monitored the patients every 5 min by measuring heart rate, systolic and mean blood pressure, respiratory rate, and oxygen saturation. The quality of recovery was also assessed using 4 different scales. The extubation time, time of headlift, and standing position were also recorded. Both groups receiving dexmedetomidine had better awakening and a lower incidence of delirium when compared to saline administration. The heart rate was lower, while the systolic pressure was higher in the two groups D1 and D0.5 compared to the NaCl with a low presence of atrioventricular blocks. The extubation time resulted significantly higher in the D1 (17 ± 6 min) compared to the D0.5 (10 ± 4 min) and NaCl (8 ± 3 min) ( p < 0.0001); the headlift time D1 (25 ± 10 min) resulted significantly longer than the NaCl group (11 ± 5 min) ( p = 0.0023) but not than the D0.5 (18 ± 9 min). No significant differences were found among the three groups for standing positioning (D1 50 ± 18 min, D0.5 39 ± 22 min, NaCl 28 ± 17 min). The preventive administration of a bolus of dexmedetomidine at a dosage of 0.5 mcg/kg or 1 mcg/kg IV during the recovery phase improves the quality of recovery in patients undergoing general anesthesia.

The purpose of this study was to determine if a continuous rate infusion (CRI) of dexmedetomidine decreases vasopressor requirements in septic dogs undergoing surgery. Vital parameters, sequential organ failure assessment (SOFA) score, vasopressor requirement, and 28-day mortality were recorded. Dogs were randomly divided into two groups: a dexmedetomidine (DEX) (1 mcg/kg/h) group and a control group (NaCl), which received an equivalent CRI of NaCl. Dogs were premedicated with fentanyl 5 mcg/kg IV, induced with propofol, and maintained with sevoflurane and a variable rate fentanyl infusion. DEX or NaCl infusions were started 10 min prior to induction. Fluid-responsive hypotensive patients received repeated Ringer's lactate boluses (2 mL/kg) until stable or they were no longer fluid-responsive. Patients that remained hypotensive following fluid boluses received norepinephrine at a starting dose of 0.05 mcg/kg/min, with increases of 0.05 mcg/kg/min. Rescue adrenaline boluses were administered (0.001 mg/kg) if normotension was not achieved within 30 min of starting norepinephrine. The NaCl group received a significantly higher dose of norepinephrine (0.8, 0.4-2 mcg/kg/min) than the DEX group (0.12, 0-0.86 mcg/kg/min). Mortality was statistically lower in the DEX group (1/10) vs. the NaCl group (5/6). Results of this study suggest that a 1 mcg/kg/h CRI of dexmedetomidine decreases the demand for intraoperative vasopressors and may improve survival in septic dogs.

Screening asymptomatic organisms (humans, animals, plants) with a high-diagnostic accuracy using point-of-care-testing (POCT) technologies, though still visionary holds great potential. Convenient surveillance requires easy-to-use, cost-effective, ultra-portable but highly reliable, in-vitro-diagnostic devices that are ready for use wherever they are needed. Currently, there are not yet such devices available on the market, but there are a couple more promising technologies developed at readiness-level 5: the Clustered-Regularly-Interspaced-Short-Palindromic-Repeats (CRISPR) lateral-flow-strip tests and the Single-Molecule-with-a-large-Transistor (SiMoT) bioelectronic palmar devices. They both hold key features delineated by the World-Health-Organization for POCT systems and an occurrence of false-positive and false-negative errors <1-5% resulting in diagnostic-selectivity and sensitivity >95-99%, while limit-of-detections are of few markers. CRISPR-strip is a molecular assay that, can detect down to few copies of DNA/RNA markers in blood while SiMoT immunometric and molecular test can detect down to a single oligonucleotide, protein marker, or pathogens in 0.1mL of blood, saliva, and olive-sap. These technologies can prospectively enable the systematic and reliable surveillance of asymptomatic ones prior to worsening/proliferation of illnesses allowing for timely diagnosis and swift prognosis. This could establish a proactive healthcare ecosystem that results in effective treatments for all living organisms generating diffuse and well-being at efficient costs., (© 2023 The Authors. Advanced Materials published by Wiley‐VCH GmbH.)

The objective of our study was to compare the efficacy of sciatic and saphenous ultrasound nerve blocks with and without US-guided obturator nerve block in dogs undergoing tibial-plateau-levelling-osteotomy (TPLO) surgery. This study was developed in two phases: identification of an ultrasound window in the inguinal region for obturator nerve block and utilization of it in dogs undergoing TPLO. Dogs were assigned randomly to one of two groups: one received the three blocks with 0.5% ropivacaine (ON group) and the second one (NoON group) with NaCl instead of ropivacaine for the obturator block. In phase 1, the obturator nerve was visible between the pectineus and the abductor muscles and was approached using an in-plane technique. It was possible to use the ultrasound window for phase two. The number of dogs that received at least one bolus of intraoperative rescue analgesia in the NoON group (12/15 dogs) was significantly higher ( p = 0.003) in comparison with the ON group (4/15). An ultrasound window to block the obturator nerve in the inguinal compartment with an in-plane technique was found. The use of this approach could produce adequate analgesia with less motor function impairment in dogs for TPLO surgery.

The aim of this study was to evaluate the effect of the transverse quadratus lumborum block (QLB LQL-T ) on time to the first postoperative rescue analgesia in dogs submitted to laparoscopic ovariectomy. A total of twenty-three female dogs were included. Dogs were randomly assigned to receive a bilateral QLB LQL-T , performed either with 0.3 mL kg -1 ropivacaine 0.5% [group QLB 0.5% ( n = 8)] or with ropivacaine 0.33% [group QLB 0.33% ( n = 8)] or a fentanyl-based protocol [group No-QLB ( n = 7)]. Dogs were premedicated intravenously (IV) with fentanyl 5 mcg kg -1 , general anesthesia was induced IV with propofol and maintained with sevoflurane. Invasive mean arterial pressure (MAP) values were recorded five minutes before and five minutes after performing the QLB LQL-T . The short-form of the Glasgow composite measure pain scale was used every hour after extubation, and methadone 0.2 mg kg -1 was administered IV when pain score was ≥5/24. Kolmogorov-Smirnov test, ANOVA test combined with Tukey post hoc test, Student's T-test and Chi-square test were used to analyze data; p < 0.05. Time from QLB LQL-T to the first rescue analgesia was significantly longer in QLB 0.5% than in group QLB 0.33% and No-QLB. MAP pre- and post-block decreased significantly only in group QLB 0.33% .

Kelvin probe force microscopy (KPFM) allows the detection of single binding events between immunoglobulins (IgM, IgG) and their cognate antibodies (anti-IgM, anti-IgG). Here an insight into the reliability and robustness of the methodology is provided. Our method is based on imaging the surface potential shift occurring on a dense layer of ∼5 × 10 7 antibodies physisorbed on a 50 μm × 90 μm area when assayed with increasing concentrations of antigens in phosphate buffer saline (PBS) standard solutions, in air and at a fixed scanning location. A comprehensive investigation of the influence of the main experimental parameters that may interfere with the outcomes of KPFM immune-assay is provided, showing the robustness and reliability of our approach. The data are supported also by a thorough polarization modulation infrared reflection-absorption spectroscopy (PM-IRRAS) analysis of the physisorbed biolayer, in the spectral region of the amide I, amide II and amide A bands. Our findings demonstrate that a 10 min incubation in 500 μL PBS encompassing ≈ 30 antigens (100 zM) triggers an extended surface potential shift that involves the whole investigated area. Such a shift quickly saturates at increasing ligand concentration, showing that the developed sensing platform works as an OFF/ON detector, capable of assessing the presence of a few specific biomarkers in a given assay volume. The reliability of the developed methodology KPFM is an important asset in single molecule detections at a wide electrode interface., Competing Interests: The authors declare no conflict of interest., (This journal is © The Royal Society of Chemistry.)

Herein, we report a scalable benchtop electrode fabrication method to produce highly sensitive and flexible third-generation fructose dehydrogenase amperometric biosensors based on water-dispersed 0D-nanomaterials. The electrochemical platform was fabricated via Stencil-Printing (StPE) and insulated via xurography. Carbon black (CB) and mesoporous carbon (MS) were employed as 0D-nanomaterials promoting an efficient direct electron transfer (DET) between fructose dehydrogenase (FDH) and the transducer. Both nanomaterials were prepared in water-phase via a sonochemical approach. The nano-StPE exhibited enhanced electrocatalytic currents compared to conventional commercial electrodes. The enzymatic sensors were exploited for the determination of D-fructose in model solutions and various food and biological samples. StPE-CB and StPE-MS integrated biosensors showed appreciable sensitivity (∼150 μA cm -2 mM -1 ) with μmolar limit of detection (0.35 and 0.16 μM, respectively) and extended linear range (2-500 and 1-250 μM, respectively); the selectivity of the biosensors, ensured by the low working overpotential (+0.15 V), has been also demonstrated. Good accuracy (recoveries between 95 and 116%) and reproducibility (RSD ≤8.6%) were achieved for food and urine samples. The proposed approach because of manufacturing versatility and the electro-catalytic features of the water-nanostructured 0D-NMs opens new paths for affordable and customizable FDH-based bioelectronics., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

A cohort of 47 patients is screened for pancreatic cancer precursors with a portable 96-well bioelectronic sensing-array for single-molecule assay in cysts fluid and blood plasma, deployable at point-of-care (POC). Pancreatic cancer precursors are mucinous cysts diagnosed with a sensitivity of at most 80% by state-of-the-art cytopathological molecular analyses (e.g., KRAS mut DNA). Adding the simultaneous assay of proteins related to malignant transformation (e.g., MUC1 and CD55) is deemed essential to enhance diagnostic accuracy. The bioelectronic array proposed here, based on single-molecule-with-a-large-transistor (SiMoT) technology, can assay both nucleic acids and proteins at the single-molecule limit-of-identification (LOI) (1% of false-positives and false-negatives). It comprises an enzyme-linked immunosorbent assay (ELISA)-like 8 × 12-array organic-electronics disposable cartridge with an electrolyte-gated organic transistor sensor array, and a reusable reader, integrating a custom Si-IC chip, operating via software installed on a USB-connected smart device. The cartridge is complemented by a 3D-printed sensing gate cover plate. KRAS mut , MUC1, and CD55 biomarkers either in plasma or cysts-fluid from 5 to 6 patients at a time, are multiplexed at single-molecule LOI in 1.5 h. The pancreatic cancer precursors are classified via a machine-learning analysis resulting in at least 96% diagnostic-sensitivity and 100% diagnostic-specificity. This preliminary study opens the way to POC liquid-biopsy-based early diagnosis of pancreatic-cancer precursors in plasma., (© 2023 The Authors. Advanced Materials published by Wiley-VCH GmbH.)

Objective: To evaluate the impact of a 30% end-inspiratory pause (EIP) on alveolar tidal volume (V Talv ), airway (V Daw ) and physiological (V Dphys ) dead spaces in mechanically ventilated horses using volumetric capnography, and to evaluate the effect of EIP on carbon dioxide (CO 2 ) elimination per breath (Vco 2 br -1 ), PaCO 2, and the ratio of PaO 2 -to-fractional inspired oxygen (PaO 2 :FiO 2 )., Study Design: Prospective research study., Animals: A group of eight healthy research horses undergoing laparotomy., Methods: Anesthetized horses were mechanically ventilated as follows: 6 breaths minute -1 , tidal volume (V T ) 13 mL kg -1 , inspiratory-to-expiratory time ratio 1:2, positive end-expiratory pressure 5 cmH 2 O and EIP 0%. Vco 2 br -1 and expired tidal volume (V TE ) of 10 consecutive breaths were recorded 30 minutes after induction, after adding 30% EIP and upon EIP removal to construct volumetric capnograms. A stabilization period of 15 minutes was allowed between phases. Data were analyzed using a mixed-effect linear model. Significance was set at p < 0.05., Results: The EIP decreased V Daw from 6.6 (6.1-6.7) to 5.5 (5.3-6.1) mL kg -1 (p < 0.001) and increased V Talv from 7.7 ± 0.7 to 8.6 ± 0.6 mL kg -1 (p = 0.002) without changing the V TE . The V Dphys to V TE ratio decreased from 51.0% to 45.5% (p < 0.001) with EIP. The EIP also increased PaO 2 :FiO 2 from 393.3 ± 160.7 to 450.5 ± 182.5 mmHg (52.5 ± 21.4 to 60.0 ± 24.3 kPa; p < 0.001) and Vco 2 br -1 from 0.49 (0.45-0.50) to 0.59 (0.45-0.61) mL kg -1 (p = 0.008) without reducing PaCO 2 ., Conclusions and Clinical Relevance: The EIP improved oxygenation and reduced V Daw and V Dphys , without reductions in PaCO 2 . Future studies should evaluate the impact of different EIP in healthy and pathological equine populations under anesthesia., (Copyright © 2023 Association of Veterinary Anaesthetists and American College of Veterinary Anesthesia and Analgesia. Published by Elsevier Ltd. All rights reserved.)

Antibody physisorption at a solid interface is a very interesting phenomenon that has important effects on applications such as the development of novel biomaterials and the rational design and fabrication of high-performance biosensors. The strategy selected to immobilize biorecognition elements can determine the performance level of a device and one of the simplest approaches is physical adsorption, which is cost-effective, fast, and compatible with printing techniques as well as with green-chemistry processes. Despite its huge advantages, physisorption is very seldom adopted, as there is an ingrained belief that it does not lead to high performance because of its lack of uniformity and long-term stability, which, however, have never been systematically investigated, particularly for bilayers of capture antibodies. Herein, the homogeneity and stability of an antibody layer against SARS-CoV-2-Spike1 (S1) protein physisorbed onto a gold surface have been investigated by means of multi-parametric surface plasmon resonance (MP-SPR). A surface coverage density of capture antibodies as high as (1.50 ± 0.06) × 10 12 molecules per cm -2 is measured, corresponding to a thickness of 12 ± 1 nm. This value is compatible with a single monolayer of homogeneously deposited antibodies. The effect of the ionic strength ( i s ) of the antibody solution in controlling physisorption of the protein was thoroughly investigated, demonstrating an enhancement in surface coverage at lower ionic strength. An atomic force microscopy (AFM) investigation shows a globular structure attributed to i s -related aggregations of antibodies. The long-term stability over two weeks of the physisorbed proteins was also assessed. High-performance sensing was proven by evaluating figures of merit, such as the limit of detection (2 nM) and the selectivity ratio between a negative control and the sensing experiment (0.04), which is the best reported performance for an SPR S1 protein assay. These figures of merit outmatch those measured with more sophisticated biofunctionalization procedures involving chemical bonding of the capture antibodies to the gold surface. The present study opens up interesting new pathways toward the achievement of a cost-effective and scalable biofunctionalization protocol, which could guarantee the prolonged stability of the biolayer and easy handling of the biosensing system., Competing Interests: The authors declare no conflict of interest., (This journal is © The Royal Society of Chemistry.)

Dexmedetomidine is an alpha-2 adrenergic agonist, which use had an exponential increase in human and veterinary medicine in the last 10 years. The aim of this mini review is to summarize the various uses of dexmedetomidine underlining its new applications and capabilities in the small animals' clinical activity. While this drug was born as sedative in veterinary medicine, some studies demonstrated to be effective as an analgesic both in single administration and in continuous infusion. Recent studies have also shown the role of dexmedetomidine as an adjuvant during locoregional anesthesia, increasing the duration of the sensitive block and consequently decreasing the demand for systemic analgesics. The various analgesic properties make dexmedetomidine an interesting drug for opioid-free analgesia. Some studies highlighted a potential neuroprotective, cardioprotective and vasculoprotective role of dexmedetomidine, thus conferring it a place in critical care medicine, such as trauma and septic patients. Dexmedetomidine has demonstrated to be a multitasking molecule and it is ready to face new challenges., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Di Franco, Evangelista and Briganti.)

Thin self-standing films with potential antimicrobial synergistic activity have been produced by a simple green chemical synthesis with overnight thermal treatment. Their properties have been studied by scanning electron microscopy, X-ray photoelectron spectroscopy and other techniques to understand their potential range of applications. In this work, the focus was set on the development of a potential novel and effective alternative to conventional antimicrobial materials. By creating an antimicrobial polymer blend, and using it to develop and immobilize fine (~25 nm) silver nanophases, we further aimed to exploit its film-forming properties and create a solid composite material. The resulting polymer matrix showed improved water uptake percentage and better stability in the presence of water. Moreover, the antimicrobial activity of the films, which is due to both organic and inorganic components, has been evaluated by Kirby-Bauer assay against common foodborne pathogens ( Staphylococcus aureus and Salmonella enterica ) and resulted in a clear inhibition zone of 1.2 cm for the most complex nanocomposition. The excellent performance against bacteria of fresh and 6-month-old samples proves the prospects of this material for the development of smart and biodegradable food packaging applications.

For the echocardiographic examination horses should not be sedated unless absolutely necessary because this alters cardiac dimensions and indices of function. However, some horses do not tolerate the echocardiographic procedure and require sedation to conduct the examination safely and obtain good quality images. The objective of this study was to evaluate whether the concurrent infusion of dobutamine in horses sedated with romifidine counteracts the cardiovascular changes observed with sedation alone. Twelve healthy untrained Standardbred mares were used. Three echocardiographic examinations were performed on the same day for each subject: a) without any treatment under resting conditions (WT); b) under sedation with romifidine administered intravenously (RT); c) under sedation with romifidine and concurrent intravenous infusion with dobutamine (RDT). A three-hour washout period was observed between each examination and the order of the examinations was randomly decided by rolling a dice. The measurements on the images recorded were performed offline at the end of the study protocol and at this point the operator was blinded to the horse and treatment administered. Left ventricular internal diameter (LVID) in diastole, left ventricular free wall (LVFW) in systole, and fractional shortening (FS) were higher in the WT group compared with the other two groups. No differences in the other M-mode and B-mode values were observed. A continuous rate infusion of dobutamine did not counteract the alterations caused by sedation and led to similar echocardiographic measurements to those obtained after romifidine administration., Competing Interests: The authors have declared that no competing interests exist.

Pathogens ultra-sensitive detection is vital for early diagnosis and provision of restraining actions and/or treatments. Among plant pathogens, Xylella fastidiosa is among the most threatening as it can infect hundreds of plant species worldwide with consequences on agriculture and the environment. An electrolyte-gated transistor is here demonstrated to detect X. fastidiosa at a limit-of-quantification (LOQ) of 2 ± 1 bacteria in 0.1 mL (20 colony-forming-unit per mL). The assay is carried out with a millimeter-wide gate functionalized with Xylella-capturing antibodies directly in saps recovered from naturally infected plants. The proposed platform is benchmarked against the quantitave polymerase chain reaction (qPCR) gold standard, whose LOQ turns out to be at least one order of magnitude higher. Furthermore, the assay selectivity is proven against the Paraburkholderia phytofirmans bacterium (negative-control experiment). The proposed label-free, fast (30 min), and precise (false-negatives, false-positives below 1%) electronic assay, lays the ground for an ultra-high performing immunometric point-of-care platform potentially enabling large-scale screening of asymptomatic plants., (© 2022 The Authors. Advanced Science published by Wiley-VCH GmbH.)

Early diagnosis in a premalignant (or pre-invasive) state represents the only chance for cure in neoplastic diseases such as pancreatic-biliary cancer, which are otherwise detected at later stages and can only be treated using palliative approaches, with no hope for a cure. Screening methods for the purpose of secondary prevention are not yet available for these cancers. Current diagnostic methods mostly rely on imaging techniques and conventional cytopathology, but they do not display adequate sensitivity to allow valid early diagnosis. Next-generation sequencing can be used to detect DNA markers down to the physical limit; however, this assay requires labeling and is time-consuming. The additional determination of a protein marker that is a predictor of aggressive behavior is a promising innovative approach, which holds the potential to improve diagnostic accuracy. Moreover, the possibility to detect biomarkers in blood serum offers the advantage of a noninvasive diagnosis. In this study, both the DNA and protein markers of pancreatic mucinous cysts were analyzed in human blood serum down to the single-molecule limit using the SiMoT (single-molecule assay with a large transistor) platform. The SiMoT device proposed herein, which exploits an inkjet-printed organic semiconductor on plastic foil, comprises an innovative 3D-printed sensing gate module, consisting of a truncated cone that protrudes from a plastic substrate and is compatible with standard ELISA wells. This 3D gate concept adds tremendous control over the biosensing system stability, along with minimal consumption of the capturing molecules and body fluid samples. The 3D sensing gate modules were extensively characterized from both a material and electrical perspective, successfully proving their suitability as detection interfaces for biosensing applications. KRAS and MUC1 target molecules were successfully analyzed in diluted human blood serum with the 3D sensing gate functionalized with b-KRAS and anti-MUC1, achieving a limit of detection of 10 zM and 40 zM, respectively. These limits of detection correspond to (1 ± 1) KRAS and (2 ± 1) MUC1 molecules in the 100 μL serum sample volume. This study provides a promising application of the 3D SiMoT platform, potentially facilitating the timely, noninvasive, and reliable identification of pancreatic cancer precursor cysts., (© 2022. The Author(s).)

Bioelectronic transducing surfaces that are nanometric in size have been the main route to detect single molecules. Though enabling the study of rarer events, such methodologies are not suited to assay at concentrations below the nanomolar level. Bioelectronic field-effect-transistors with a wide (μm 2 -mm 2 ) transducing interface are also assumed to be not suited, because the molecule to be detected is orders of magnitude smaller than the transducing surface. Indeed, it is like seeing changes on the surface of a one-kilometer-wide pond when a droplet of water falls on it. However, it is a fact that a number of large-area transistors have been shown to detect at a limit of detection lower than femtomolar; they are also fast and hence innately suitable for point-of-care applications. This review critically discusses key elements, such as sensing materials, FET-structures, and target molecules that can be selectively assayed. The amplification effects enabling extremely sensitive large-area bioelectronic sensing are also addressed.

Dogs differ greatly in size, heart (HR) and breathing rates (BR). In addition, they have a clear Respiratory Sinus Arrhythmia (RSA) at rest. Therefore, better than any other mammalian species, dogs offer an opportunity to test whether resting RSA varies with body weight, HR or BR. Sequences of inter-beat-intervals (IBI, ms) a few-minutes long were collected in twenty-three resting dogs of different sizes, together with pneumograms. IBI variability was quantified by standard time-domain criteria. From beat-to-beat instantaneous heart rate (hR, beats/min), RSA was the difference between inspiratory peak (hR-peak) and expiratory trough (hR-trough), in percent of mean HR. RSA averaged 40.1 % ±4.5, or more than three times that of humans, with large inter-animal variability. On average, RSA contributed 38 % of the total IBI variability. RSA did not differ between sexes and did not correlate with body weight. It had modest negative correlations with HR (P < 0.05) and BR (P < 0.05), and a very strong negative correlation with hR-trough (P < 0.001). In two separate dogs, during panting, RSA was absent. In the transition from resting to panting, RSA continued like at rest for several breaths, despite the tachypnea, underlying the importance of central mechanisms in the origin of RSA. In conclusion, RSA in dogs is very large and explains less than half of their sinus arrhythmia. Rather than HR, BR or hR-peak, changes in the vago-sympathetic control, represented by hR-trough, are the most likely source of variability of RSA among subjects., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Objective: To evaluate two transducer and needle handling methods, along the visual axis (AL) and across the visual axis (AC), in non-skilled and skilled clinicians., Study Design: Prospective randomized crossover study., Method: A total of 26 students with no ultrasound locoregional anaesthesia experience (non-skilled group) and six clinicians experienced and familiar with ultrasound locoregional anaesthesia (skilled group) were enrolled. The non-skilled group was asked to perform two tasks: the first on a phantom and the second on canine cadavers, whilst the skilled group performed only the second task. The tasks consisted of guiding the tip of the needle to a target point (simulated nerve on the jelly phantom and sciatic nerve on the cadavers) using two different methods of needle handling-AL or AC. All operators performed each task three times for each method. The time to drive the needle to the target for the two methods was analysed with a paired Student t test, and the number of times the needle was not visualized on the screen between the groups was compared using an unpaired Student t test. Data are presented as mean ± standard deviation. Value of p < 0.05 was considered significant., Results: The AL method, compared with the AC method, resulted in shorter performance time in both skilled (9 ± 5 versus 20 ± 8 seconds for the second task) and non-skilled groups (9 ± 8 versus 17 ± 15 seconds for the first task and 18 ± 11 versus 32 ± 26 seconds for the second task)., Conclusion and Clinical Relevance: In both groups, the AL method significantly reduced the time to complete the task. Results from this study indicate that the AL method should be the preferred method for learning/teaching ultrasound-guided regional anaesthesia., (Copyright © 2020 Association of Veterinary Anaesthetists and American College of Veterinary Anesthesia and Analgesia. Published by Elsevier Ltd. All rights reserved.)

Penile cancer (PC) is a typical tumor of non-industrialized countries. The incidence is 20-30 times higher in Africa and South America, considering the elevated prevalence of sexually transmitted diseases. Histologically, PC includes squamous cell carcinoma (SCPC), the most frequent, and nonsquamous carcinoma (NSCPC). Early diagnosis is the goal, whereas later diagnosis relates to poor functional outcomes and worse prognosis. The 5-year survival rate is 85% for patients with histologically regional negative lymph nodes, compared to 29%-40% for those with histologically regional positive lymph nodes. To date no new drugs are approved, and there are few new data about molecular mechanisms underlying tumorigenesis. The SCPC remains a rare tumor and the current therapeutic algorithm is based principally on retrospective analysis and less on prospective trials. In this review article, biomarkers of prognosis and efficacy of current treatments are summarized with a focus on those that have the potential to affect treatment decision-making in SCPC.

Single-molecule sensing is becoming a major driver in biomarker assays as it is foreseen to enable precision medicine to enter into everyday clinical practice. However, among the single-molecule detection methods proposed so far, only a few are fully exploitable for the ultrasensitive label-free assay of biofluids. Firstly introduced single-molecule sensing platforms encompass low-background-noise fluorescent microscopy as well as plasmonic and electrical nanotransducers; these are generally able to sense at the nanomolar concentration level or higher. Label-based single-molecule technologies relying on optical transduction and microbeads that can scavenge and detect a few biomarkers in the bulk of real biofluids, reaching ultralow detection limits, have been recently commercialized. These assays, thanks to the extremely high sensitivity and convenient handling, are new trends in the field as they are paving the way to a revolution in early diagnostics. Very recently, another new trend is the label-free, organic bioelectronic electrolyte-gated large transistors that can potentially be produced by means of large-area low-cost technologies and have been proven capable to detect a protein at the physical limit in real bovine serum. This article offers a bird's-eye view on some of the more significant single-molecule bioanalytical technologies and highlights their sensing principles and figures-of-merit such as limit of detection, need for a labelling step, and possibility to operate, also as an array, directly in real biofluids. We also discuss the new trend towards single-molecule proof-of-principle extremely sensitive technologies that can detect a protein at the zeptomolar concentration level involving label-free devices that potentially offer low-cost production and easy scalability.

The increasing interest in technologies capable of tracking a biomarker down to the physical limit points toward new opportunities in early diagnostics of progressive diseases. Indeed, single-molecule detection technologies are foreseen to enable clinicians to associate the tiniest increase in a biomarker with the progression of a disease, particularly at its early stage. Bioelectronic organic transistors represent an extremely powerful tool to achieve label-free and single-molecule detection of clinically relevant biomarkers. These electronic devices are millimetric in size and in the future could be mass-produced at low cost. The core of the single molecule with a large transistor (SiMoT) platform, based on an electrolyte-gated field-effect transistor, is a gold gate electrode biofunctionalized with a self-assembled monolayer, a densely packed layer of recognition elements. So far, only the SiMoT detection of proteins, using the corresponding antibodies as recognition elements, has been reported. In this study, the SiMoT sensing response toward genomic biomarkers is proposed. Herein, the gate is functionalized with a genomic biomarker for multiple sclerosis (miR-182). This is relevant, not only because a limit of detection of a single molecule is achieved but also because it proves that the SiMoT label-free, single-molecule detection principle is the only one of its kind that can detect, by means of the same platform, both protein and genomic markers.

Early diagnosis of the infection caused by human immunodeficiency virus type-1 (HIV-1) is vital to achieve efficient therapeutic treatment and limit the disease spreading when the viremia is at its highest level. To this end, a point-of-care HIV-1 detection carried out with label-free, low-cost, and ultra-sensitive screening technologies would be of great relevance. Herein, a label-free single molecule detection of HIV-1 p24 capsid protein with a large (wide-field) single-molecule transistor (SiMoT) sensor is proposed. The system is based on an electrolyte-gated field-effect transistor whose gate is bio-functionalized with the antibody against the HIV-1 p24 capsid protein. The device exhibits a limit of detection of a single protein and a limit of quantification in the 10 molecule range. This study paves the way for a low-cost technology that can quantify, with single-molecule precision, the transition of a biological organism from being "healthy" to being "diseased" by tracking a target biomarker. This can open to the possibility of performing the earliest possible diagnosis.

Robust electrolyte-gated organic field-effect-transistors (OFETs) are particularly needed for the development of biosensing devices. However, when a FET biosensor operates in aqueous environments or even in real biological fluids, some critical issues may arise due to the possible lack of environmental long-term and/or operational stability. An important source of instability is associated with the degradation of the organic electronic channel materials such as for instance, poly-3-hexylthiophene (P3HT), a benchmark commercially available p-type organic semiconductor. In this work, the investigation of critical parameters, such as the control over spurious electrochemical phenomena as well as the operating conditions that can affect water-gated OFETs lifetime, is reported, together with a proposed modeling of the P3HT stability curve over 1 week in water. The investigation of possible morphological/chemical modifications occurring at the polymer surface after operating in water for 2 weeks was carried out. Moreover, it is proven how the addition of a gel layer can extend the P3HT based water-gated OFET shelf life up to 2 months., (Copyright © 2019 Picca, Manoli, Macchia, Tricase, Di Franco, Scamarcio, Cioffi and Torsi.)

In the last decade, saliva has been suggested as non-invasive diagnostic fluid, suitable for clinical use alternatively to blood serum and plasma. However, the clinical applicability of saliva has been hampered so far by the inadequate sensitivity of current methods to detect the lower salivary concentrations of many biomarkers monitored in blood products. Herein, a label-free biosensor based on electrolyte-gated organic thin-film transistor (EGOTFT) has been developed for the detection at the physical limit of C-reactive protein (CRP) in human saliva. CRP is a key relevant biomarker for inflammatory processes and is routinely monitored for many clinical purposes. Herein, an electrolyte-gated thin-film transistor (EGOTFT) has been proposed as a transducer of the biorecognition event taking place at the gate electrode, functionalized with a self-assembled monolayer (SAM) of highly densely packed capturing anti-CRP proteins. Thanks to the SAM, the biosensing platform herein proposed is endowed with ultra-high sensitivity, along with an extremely high selectivity, assessed by measuring the dose curves of CRP interacting with a bovine serum albumin-functionalized gate. Moreover, the biosensing platform is compatible with low-cost fabrication techniques and applicable to the ultra-sensitive detection of a plethora of clinically relevant biomarkers. Therefore, the EGOTFT device herein proposed, being able to operate in physiologically relevant fluids such as saliva, will set the ground to a major revolution in biosensing applications for early clinical detection.

Simulations of stochastic processes play an important role in the quantitative sciences, enabling the characterisation of complex systems. Recent work has established a quantum advantage in stochastic simulation, leading to quantum devices that execute a simulation using less memory than possible by classical means. To realise this advantage it is essential that the memory register remains coherent, and coherently interacts with the processor, allowing the simulator to operate over many time steps. Here we report a multi-time-step experimental simulation of a stochastic process using less memory than the classical limit. A key feature of the photonic quantum information processor is that it creates a quantum superposition of all possible future trajectories that the system can evolve into. This superposition allows us to introduce, and demonstrate, the idea of comparing statistical futures of two classical processes via quantum interference. We demonstrate interference of two 16-dimensional quantum states, representing statistical futures of our process, with a visibility of 0.96 ± 0.02.

Although the cross-kingdom transfer of vegetable miRNAs (miRNAs) in mammalian species, including humans, is still controversial, recent studies have rejected this theory. Based on these recent studies, we hypothesized that artichoke-derived miRNAs (cca-miRNAs) are not adsorbed into human intestinal cells after cooking and in vitro digestion. In order to test this hypothesis, we evaluated miRNA (cca-miRNAs) in the edible part of globe artichokes (head portion), after cooking and digestion by an in vitro digestion system. The cca-miRNA levels were analyzed by real-time PCR (RT-qPCR), and those that withstood cooking and digestion conditions were further analyzed for their bioavailability using an in vitro system (Caco-2/TC7 cell clone). We detected 20 cca-miRNAs after cooking, 5 of which were statistically down-regulated in comparison with uncooked samples. Only 4 cca-miRNAs were found after in vitro digestion. By using scanning electron microscopy (SEM), we also evaluated the extracellular vesicles (EVs) in homogenized artichoke as possible miRNA transporters. However, approximately 81% were degraded after cooking, while the remaining EVs had changed shape from round to elliptical. Finally, we detected no cell-free cca-miRNAs, miRNAs bound to protein complex, and no cca-miRNAs encapsulated in EVs inside Caco-2 cells or in basolateral medium after bioavailability experiments. In conclusion, the data from the present study agrees with recent findings that the human small intestine does not uptake dietary miRNAs from raw or cooked artichoke heads., (Copyright © 2018 Elsevier Inc. All rights reserved.)

We aimed at producing a hydrogel from a chitosan (CS) derivative soluble in physiological conditions to avoid any purification step thus allowing to use the materials also as an in-situ forming material. So, we crosslinked glycol chitosan (GCS) with poly(ethylene glycol) diglycidyl ether (PEGDE) in water at 37 °C. The scaffolds, referred as GCS-PEG, were specifically designed to be used as wound dressing materials as such (after crosslinking) or as in-situ forming materials. Different amounts of PEGDE were tested. The obtained scaffolds showed macroscopic pores and a tailorable swelling in water by controlling the crosslinking degree. Moreover, GCS-PEG scaffolds displayed a significant antimicrobial activity against Staphylococcus aureus. In-vivo study using the chick embryo choriallantoic membrane resulted in a highly pronounced pro-angiogenic activity suggesting important tissue regeneration properties. Moreover, the employed materials are commercially available, no organic solvents are required and the scaling up is quite predictable., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Label-free single-molecule detection has been achieved so far by funnelling a large number of ligands into a sequence of single-binding events with few recognition elements host on nanometric transducers. Such approaches are inherently unable to sense a cue in a bulk milieu. Conceptualizing cells' ability to sense at the physical limit by means of highly-packed recognition elements, a millimetric sized field-effect-transistor is used to detect a single molecule. To this end, the gate is bio-functionalized with a self-assembled-monolayer of 10 12 capturing anti-Immunoglobulin-G and is endowed with a hydrogen-bonding network enabling cooperative interactions. The selective and label-free single molecule IgG detection is strikingly demonstrated in diluted saliva while 15 IgGs are assayed in whole serum. The suggested sensing mechanism, triggered by the affinity binding event, involves a work-function change that is assumed to propagate in the gating-field through the electrostatic hydrogen-bonding network. The proposed immunoassay platform is general and can revolutionize the current approach to protein detection.

Hydrogels are among the most common materials used in drug delivery, as polymeric micelles are too. They, preferentially, load hydrophilic and hydrophobic drugs, respectively. In this paper, we thought to combine the favorable behaviors of both hydrogels and polymeric micelles with the specific aim of delivering hydrophilic and hydrophobic drugs for dual delivery in combination therapy, in particular for colon drug delivery. Thus, we developed a hydrogel by UV crosslinking of a methacrylated (MA) amphiphilic derivative from inulin (INU) (as known INU is specifically degraded into the colon) and vitamin E (VITE), called INVITEMA. The methacrylated micelles were physicochemically characterized and subjected to UV irradiation to form what we called the "nanogrids". The INVITEMA nanogrids were characterized by DSC, SEM, TEM, water uptake and beclomethasone dipropionate (BDP) release. In particular, the release of the hydrophobic drug was specifically assessed to verify that it can spread along the hydrophilic portions and, therefore, effectively released. These systems can open new pharmaceutical applications for known hydrogels or micelle systems, considering that in literature only few examples are present.

Herein a label-free immunosensor based on electrolyte-gated organic field-effect transistor (EGOFET) was developed for the detection of procalcitonin (PCT), a sepsis marker. Antibodies specific to PCT were immobilized on the poly-3-hexylthiophene (P3HT) organic semiconductor surface through direct physical adsorption followed by a post-treatment with bovine serum albumin (BSA) which served as the blocking agent to prevent non-specific adsorption. Antibodies together with BSA (forming the whole biorecognition layer) served to selectively capture the procalcitonin target analyte. The entire immunosensor fabrication process was fast, requiring overall 45min to be completed before analyte sensing. The EGOFET immunosensor showed excellent electrical properties, comparable to those of bare P3HT based EGOFET confirming reliable biosensing with bio-functional EGOFET immunosensor. The detection limit of the immunosensor was as low as 2.2pM and within a range of clinical relevance. The relative standard deviation of the individual calibration data points, measured on immunosensors fabricated on different chips (reproducibility error) was below 7%. The developed immunosensor showed high selectivity to the PCT analyte which was evident through control experiments. This report of PCT detection is first of its kind among the electronic sensors based on EGOFETs. The developed sensor is versatile and compatible with low-cost fabrication techniques., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Hybrids consisting of silver nanoparticles (in varying fractions) and of TiOx/ZnO were prepared via top-down ion beam sputtering (IBS) deposition on silicon substrates. The deposited nanomaterials were characterized by scanning electron microscopy and X-ray photoelectron spectroscopy. It is shown that such composites represent a viable substrate for use in both surface enhanced Raman spectroscopy (SERS) and surface enhanced infrared absorption spectroscopy (SEIRAS), as exemplarily shown for crystal violet as the model analyte. The C-H bending mode at about 1181 cm -1 and the C-N vibration at 1361 cm -1 observed in the SERS and SEIRAS spectra, respectively, have been used as analytical signal. The substrate consisting of TiOx NPs with 33% fraction of silver provides the strongest enhancement in SERS (up to 10,000-fold), while TiOx/AgNPs with thickness of 2 and 1 nm in ion beam sputtering, respectively, provides the best sensitivity in SEIRAS. The substrates also display photocatalytic activity as shown by the degradation of adsorbed crystal violet under ultraviolet irradiation. Graphical abstract Schematic of the preparation of hybrid substrates consisting of Ag and TiOx/ZnO nanoparticles via ion beam sputtering deposition. They were applied in both surface enhanced Raman and surface enhanced infrared absorption spectroscopies using crystal violet as model analyte, showing enhancements up to >10,000-fold in Raman.

Bioconjugated gold surfaces constitute interesting platforms for biosensing applications. The immobilization of antibodies such as anti-immunoglobulin G and M (anti-IgG and anti-IgM) on gold electrodes via self-assembled monolayers (SAMs) is here studied as a model system for further immunoassays development. The biolayer is characterized by means of X-ray photoelectron spectroscopy (XPS), atomic force microscopy (AFM), a dedicated thin-film transistor (TFT)-based platform and electrochemical surface plasmon resonance (EC-SPR). XPS analysis confirms the presence of all the chemical species involved in the fabrication process as well as the covalent attachment of the antibodies with high reproducibility. Visualization of the biolayer topography by AFM shows nanostructures with a thickness consistent with the actual size of the protein, which is also verified by SPR measurements. EC-SPR allows taking advantage of complementary electrochemical and optical signals during the functionalization steps. Moreover, the functionalization of gold leads to a change in the work function, which is demonstrated in an electrolyte gated thin-film transistor configuration. Such configuration enables also to evaluate the electrostatic changes occurring on the gate that are connected with the threshold voltage shifts. The data support that functional biomodified gold surfaces can be reproducibly prepared, which is a prerequisite for further biosensor development., (© 2017 The Authors. Published by WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Electrical double layer (EDL) thin film transistors (TFTs) are an interesting class of transistors that use an electrolyte as the gating medium. Recently it has been demonstrated that pure organic solvents can also be used as gating media for TFTs without the addition of exogenous electrolytes. Here we present a systematic study of the performances of TFTs based on two different semiconductors (P3HT and ZnO) gated through nine different solvents either pure or loaded with NaCl. The nature of the solvent impacts the transfer characteristics of the TFT through a change in the gating capacitance while the threshold voltage remains unaffected. Depending on the polarity of solvents, addition of NaCl gives rise to different responses. TFTs gated through highly polar solvents are unaffected by the salt concentration while for low polarity solvents the output current increases with salt up to a plateau. Furthermore, when the semiconductor surface is covered with a high capacitance thin dielectric layer, the TFT output current becomes dependent on the NaCl concentration also for high polarity solvents. This phenomenology was rationalized considering the different contributions of Helmholtz and Guy-Chapman EDLs to the capacitance and the dielectric saturation that decreases the solvent dielectric constant within the Helmholtz EDL.

Silver nanophases are routinely used as bioactive additives in commercial products. Besides their antimicrobial activity, nanosafety issues regarding the application of (silver-based) nanoantimicrobials should be considered, as well. In this study, we modified polyurethane foams, typically employed in air filtration and stuffing, by photodeposited silver nanoparticles for preparing hybrid materials (Ag-PU) with antibacterial properties. The composite materials were characterized in terms of morphology, surface chemical composition, ionic release in contact media, bioactivity, as well as whole nanoparticle release. Cytocompatibility was also assessed on 3T3 mouse fibroblasts. The proposed systematic approach allows for defining suitable composite final properties, in terms of bioactivity and safety, by properly tuning the deposition parameters.