Surface enhanced resonance Raman and luminescence on plasmon active nanostructured cavities

Presented here are studies of the impact of excitation angle on surface enhanced Raman and luminescence spectroscopy of dye immobilised on a plasmon active nanocavity array support. Results show that both Raman and luminescence intensities depend on the angle of incidence consistent with the presence of cavity supported plasmon modes. Dependence of scattering or emission intensity with excitation angle occurs over the window of observation

Self-Powered Microfluidic Device for Rapid Assay of Antiplatelet Drugs

We report the development of a microfluidic device for the rapid assay in whole blood of platelet-protein interactions indicative of the efficacy of antiplatelet drugs—e.g., aspirin and Plavix, two of the world’s most widely used drugs—in cardiovascular patients. Because platelet adhesion to surface-confined protein matrices is modulated by fluid shear rates at the blood/protein interface, and because such binding is a better indicator of platelet function than platelet self-aggregation, we designed, fabricated, and characterized the performance of a family of disposable, self-powered microfluidic chips with well-defined flow and interfacial shear rates suitable for small blood volumes (≤ 200 µL). We report a simple technique to fabricate single-use self-powered chips incorporating shear control, “SpearChips”. These parallel-plate flow devices integrate on-chip vacuum-driven blood flow, using a pre-degassed elastomer component to obviate active pumping, with microcontact-printed arrays of 6-µm-diameter fluorescently-labeled fibrinogen dots on a poly(cycloolefin) base plate as a means to quantitatively count platelet-protein binding events. The use of SpearChips to assess in whole blood samples the effects of GPIIb/IIIa and P2Y12 inhibitors—two important classes of “antiplatelet” drugs—is reported

Pulsed plasma physical vapour deposition approach towards the facile synthesis of multilayer and monolayer graphene for anticoagulation applications

We demonstrate the growth of multilayer and single layer graphene on copper foil using bipolar pulsed direct current (DC) magnetron sputtering of a graphite target in pure Ar atmosphere. Single layer and few layer graphene films (SG and FLG) are deposited at temperatures ranging from 700-920 °C in less than 30 minutes. We find that the deposition and post-deposition annealing temperatures influence the layer thickness and quality of the graphene films formed. The films were characterized using atomic force microscopy (AFM), scanning electron microscopy (SEM), High resolution transmission electron microscopy (HRTEM), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS) and optical transmission spectroscopy techniques. Based on the above studies, a diffusion controlled mechanism was proposed for the graphene growth. A single step whole blood assay was used to investigate the anticoagulant activity of graphene surfaces. Platelet adhesion, activation and morphological changes on the graphene/glass surfaces compared to bare glass were analysed using fluorescence microscopy and SEM techniques. We have found significant suppression of the platelet adhesion, activation and aggregation on the graphene covered surfaces compared to the bare glass, indicating the anticoagulant activity of the deposited graphene films. Our production technique represents an industrially relevant method for the growth of single and few layer graphene for various applications including the biomedical field

Ethnobiology, ethnobotany, ethnomedicine and traditional knowledge with special reference to India

Abstract Ethnobiology is the scientific study of the plants and animals as treated or used by different traditional communities. Early man looked for the best nutritious food to have a healthy and disease free long life from the surrounding environment. This effort has resulted in selecting a large number of food items by human communities who lived in different parts of the world. The early humans perhaps combined instinct with indulgence to select his food items. Countless members from various human communities who spread to the different parts of the world, continued to expand the food basket. Since the early 1970s, different groups in various Universities and Research Institutions have been working on ethnobotany and traditional knowledge system of the region and published several reports. Most of the publications were concerned with ethnobotany or agricultural operations including shifting cultivation and festivals of the region. Ethnobotanical reports were mainly on ethnomedicinal plants with a few publications on food and beverages. The ethnomedicinal publications in most cases cited only the names of plants, used without going into the details of the method of use, the quantum of use and other related aspects. During 1980s, the Ministry of Environment and Forests (MoEF), Govt. of India launched an All India Co-ordinated Research Project on Ethnobiology (AICRPE), to document ethnobotanical and ethnozoological informations on plants and animals used by the indigenous people of India. The growth and development of ethnobotanical studies in India and elsewhere are briefly reviewed in this article

Reducing the environmental impact of surgery on a global scale: systematic review and co-prioritization with healthcare workers in 132 countries

Abstract Background Healthcare cannot achieve net-zero carbon without addressing operating theatres. The aim of this study was to prioritize feasible interventions to reduce the environmental impact of operating theatres. Methods This study adopted a four-phase Delphi consensus co-prioritization methodology. In phase 1, a systematic review of published interventions and global consultation of perioperative healthcare professionals were used to longlist interventions. In phase 2, iterative thematic analysis consolidated comparable interventions into a shortlist. In phase 3, the shortlist was co-prioritized based on patient and clinician views on acceptability, feasibility, and safety. In phase 4, ranked lists of interventions were presented by their relevance to high-income countries and low–middle-income countries. Results In phase 1, 43 interventions were identified, which had low uptake in practice according to 3042 professionals globally. In phase 2, a shortlist of 15 intervention domains was generated. In phase 3, interventions were deemed acceptable for more than 90 per cent of patients except for reducing general anaesthesia (84 per cent) and re-sterilization of ‘single-use’ consumables (86 per cent). In phase 4, the top three shortlisted interventions for high-income countries were: introducing recycling; reducing use of anaesthetic gases; and appropriate clinical waste processing. In phase 4, the top three shortlisted interventions for low–middle-income countries were: introducing reusable surgical devices; reducing use of consumables; and reducing the use of general anaesthesia. Conclusion This is a step toward environmentally sustainable operating environments with actionable interventions applicable to both high– and low–middle–income countries

Site selective surface enhanced Raman on nanostructured cavities

Presented here are angle dependence studies on the surface enhanced Raman (SER) signal obtained from dye placed on plasmon active nanocavity arrays. A comparative study was carried out between two modified array supports. One array had dye placed only on the interior walls of the cavities in the array. The other array had dye placed only on its top flat surface. Results show that Raman intensities as a function of angle depend on the location of the dye on the array; this was interpreted to arise from the presence of different plasmon polariton modes in these sites.Author has checked copyrightTS 02.08.1

Tunable metallic nanostructures using 3D printed nanosphere templates

The use of two-photon 3D printing to create templates for fabricating reproducible and tunable metallic nanostructures is described. The approach allows the structure of the template to be designed specifically for particular applications, e.g., fluid flow control, surface enhanced Raman spectroscopy, metal enhanced fluorescence etc. Here, we show that this method offers excellent control of the size, pitch and packing of spheres on both conducting and insulating substrates, unlike nanosphere lithography. Gold is deposited through these templates and the template then removed using a plasma etching method. In this way, gold nanotriangles, nanodiamonds and nanocavities have been created and characterized using SEM to determine the accuracy of the structures compared to the software designs. Keywords: 3D printing, Lithography, Metal nanostructures, Electrodepositio