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Screen printed carbon electrodes (SPCEs) are widely used in the field of electrochemical sensors, especially in the areas of food, water, environmental quality, and healthcare applications. In this context, microband SPCEs were fabricated on Whatman paper, overhead projection (OHP) sheet and cotton textile substrates for the development of cost-effective electrochemical biosensors. The fabricated electrodes were subjected to three consecutive processes such as thermal, electrochemical and oxygen plasma treatment. Surface morphologies of SPCEs after each treatment stage were observed using scanning electron microscope for process standardization. Electrochemical performances of the fabricated SPCEs were analyzed using cyclic voltammetry. SPCEs on OHP substrate exhibited a single electron transfer rate at ΔEp of 57 mV and ipa/ipc = 1 (n = 3) with significant repeatability and reproducibility compared to SPCEs on paper and textile substrates. The role of activation of edge plane pyrolytic graphite of SPCEs in achieving the reversible reaction with single electron transfer characteristics has been analysed and reported. The effectiveness of the activated SPCEs on the OHP substrate was tested by detecting 1 mM of uric acid and ascorbic acid with KCl as an electrolyte.

According to the World Health Organization (WHO), cardiovascular disease (CVD) is the leading cause of death in the world every year. The design and development of biosensors for the detection of CVD markers could be one of the major contributions of the scientific community to society. In this context, acetic acid functionalized graphene quantum dots (fGQDs) were used as an interface for the electrochemical detection of cardiac Troponin I (cTnI). The interaction of cTnI with fGQDs for the early diagnosis of acute myocardial infarction was investigated using cyclic voltammetry (CV) and amperometry. The carbodiimide conjugation between the N-H group of cTnI and the functionalized COOH group on GQDs enabled the detection of cTnI biomarker. The same sensing mechanism was confirmed using Fourier Transform Infrared Spectrometry (FTIR). The fGQDs modified Au electrode showed remarkable electrocatalytic oxidation of cTnI with good stability and sensitivity over a linear range of 0.17 to 3 ng mL−1 and a low detection limit of 0.02 ng mL−1. Bland-Altman plots substantiate a bias between the intra-/inter-cTnI assay and calibrated cTnI assay with 95% limits of agreement (mean difference ± 1.96 SD). The aim of this study is to describe an innovative method to detect cardiac biomarker cTnI and provide preliminary data on its diagnostic capacity. At the same time, its applicability in clinical setting will have to be validated with a significant number of samples collected from patients.

Antiviral therapy requires desired intensity and duration of drug action at the site of infection to minimize adverse effects. The study aims to synthesize a nanoparticle based controlled release system for Acyclovir with required loading and maintenance doses to achieve steady-state plasma concentration for once-daily therapy. The amount of Acyclovir required for 24 h therapy was calculated to be 100 mg, which is approximately 10 fold reduced oral dose. Accordingly, nanoparticles with spherical and smooth surface were synthesized using hybrid polymer blends of polyvinyl pyrrolidone with ethyl cellulose or eudragit RSPO. Physical and chemical interactions between the drug and polymers favoured the formation of stable nanoparticles. Optimized nanoparticles with 80% entrapment exhibited size and surface charge of 100 nm and +26.1 mV respectively. In situ gels incorporated with 20% free drug and 80% Acyclovir loaded nanoparticles showed immediate sol–gel transition at 35 °C–37 °C with gel viscosity ranging between 1000 and 10 000 mPa s. The expected pH independent drug release profile was obtained in 0.1 N HCl, phosphate buffer, simulated vaginal and tear fluids. Ex vivo permeability was significantly higher through cornea than stomach and rectal membranes. Uptake of nanoparticles into human corneal epithelial cell lines was spontaneous. Foam spray was developed for optimized in situ gels for site specific action through vaginal or rectal administration. The bubble size, relative foam density, collapse time, drug content per puff and stability of the foam spray formulations proved its suitability for effective drug delivery. Hence, a unique dosage form achieving predicted release profile through diverse routes was well demonstrated.

Chandraprabha Vati (CPV), a multi-ingredient phyto formulation, is widely used in Ayurveda for the treatment of liver and kidney disorders. In this study, we attempt to elucidate the mode of action of CPV. We specifically focus on the effects of CPV on the transcriptional regulation of Pregnane-X-Receptor (PXR) and its subsequent effects on interleukins, Peroxisome Proliferator-Activated Receptor-γ (PPARγ) and type 4 Glucose Transporter (GLUT4). Our results show that CPV up-regulates PXR moderately in contrast to its individual ingredients such as chebulinic acid or linalool that down regulate PXR. Further, the expression of Cytochrome P450 3A4 (CYP3A4), the gene involved in drug elimination, is only moderately up-regulated by CPV, again in contrast to the effect of some of its ingredients. CPV down regulates the levels of pro-inflammatory cytokines and upregulates the levels of PPARγ, which in turn upregulates GLUT4 expression. These together suggest that the therapeutic properties of CPV can be attributed to its multi-pronged action, viz., prevention of inflammation, moderate expression of PXR that activates several downstream pathways and tight regulation of CYP3A4 thereby slowing down the elimination of the chemical constituents. In addition, these results emphasize on the need for multi-ingredient approach towards designing effective therapeutic formulations.

Experiments were performed on the synthesis of magnesium oxide nanoparticles (30–40 nm), followed by their dispersion in propylene glycol to prepare stable MgO–propylene glycol nanofluids through extensive probe ultrasonication for 25 h. The influence of MgO nanoparticle concentration (0–2 vol%) and temperature on viscosity and thermal conductivity of MgO–propylene glycol nanofluids was investigated. While the relative viscosity of the nanofluid decreased with nanoparticle concentration to a temperature of 30 °C, the relative viscosity–nanoparticle concentration exhibited a minimum at 1 vol% in the temperature range of 35–60 °C. The enhancement in thermal conductivity of nanofluids increased linearly with nanoparticle concentration and was found to be independent of temperature, with an average enhancement of ∼20% for 2 vol% MgO–propylene glycol nanofluid. Our results show that the thermal conductivity enhancement in MgO–propylene glycol can be attributed to both interfacial layering and Brownian motion.

Experiments were performed on the preparation and characterization of CuO-propylene glycol nanofluids. The influence of nanoparticle concentration and temperature on nanofluid viscosity reveals existence of a range of nanoparticle concentration and temperature in which the viscosity of nanofluid is lower than that of propylene glycol, possibly due to interactions between nanoparticles and propylene glycol. A temperature-independent, thermal conductivity enhancement of 38% was obtained for nanoparticle concentration of 1.5 vol% over a temperature range of 10-60 degrees C. We believe that particle clustering contributes to the thermal conductivity enhancement in CuO-propylene glycol nanofluids.

Ethnopharmacological relevance Herbal and herbo-mineral preparations are being traditionally used in Indian medicines. The herbo-mineral preparations have several benefits that have been instrumental in their widespread use in treatment of different disorders by traditional medicinal practitioners. These include better stability, lower dosage, ease of storability and sustained availability. Naga bhasma (lead sulphide ash), a traditional Indian herbo-mineral medication prepared using lead and several herbal ingredients, has been used as an oral medicine in India for many years for the treatment of diabetes, spleen enlargement, diarrhoea and various skin diseases. The elaborate preparation protocol involved in the traditional medicines is believed to modify the toxic nature of the precursor (metal) and adds therapeutic value. But modern scientists claim that these preparations are toxic to health as they contain large amount of metal. Many factors such as preparation based factors, chemical nature based factors, vehicle used, therapy associated factors, pharmacological factors, etc, determine whether the traditional medicines are toxic or not. This review focuses on the safety and critical issues associated with Naga bhasma— a lead based ayurvedic medicine. Materials and methods The detailed review of literature about Naga bhasma apart from other lead based formulations are carried out by utilizing the resources including, classical Indian text books, databases such as Pub med, Scopus, Science direct and few other web sources. Results Though metallic lead is known to be toxic to the biological system, no compelling evidence has been put forth to suggest any toxic manifestations of Naga bhasma . The elemental characterization of preparations containing Naga bhasma has shown extremely high levels of lead content and various parameters must be taken into consideration in deciding the safety and critical issues present in traditional medicines. As there are no molecular targets available for most of the traditional medicine, it is difficult to assure the safety in using this traditional preparation. Highly intensive research encompassing physico-chemical, engineering as well as biological aspects need to be carried out to understand the applicability of such preparations in a modern context. Conclusion As there are no molecular targets available for most of the traditional medicine, it is difficult to assure the safety in using this traditional preparation. Highly intensive research encompassing physico–chemical, engineering as well as biological aspects need to be carried out to understand the applicability of such preparations in a modern context.

Experiments were carried out on preparation of colloidal dispersions of ZnO nanoparticles in propylene glycol leading to ZnO–propylene glycol nanofluids. Thermal conductivity of these nanofluids was measured as a function of nanoparticle concentration (⩽2 vol.%), temperature (10–60 °C) and aggregate size. A strong dependence of thermal conductivity enhancement on temperature with higher enhancements at lower temperatures has been observed. Our results on temperature and aggregation dependence of thermal conductivity enhancement show that the thermal conductivity enhancement in ZnO–propylene glycol nanofluids is attributed to formation of solvation layers (liquid layers) of base fluid on the ZnO nanoparticle surfaces.

The rheological characteristics of ZnO–propylene glycol nanofluid have been studied over a temperature range of 10–140 °C and nanoparticle concentration range of 0–2 vol%. The addition of ZnO nanoparticles (35–40 nm) to propylene glycol (PG) weakens the inter-molecular hydrogen bonding in propylene glycol. This is reflected in the reduced values of viscosity for nanoparticle dispersions (nanofluids) compared to that of base fluid. The viscosity decrease is more pronounced at lower temperatures and at higher nanoparticle concentration. The percentage reduction in viscosity is 53 and 32 % at 10 and 28 °C, respectively, for 2 vol% ZnO–propylene glycol nanofluid compared to pure PG. This dispersion has immense potential for cooling application owing to lower viscosity. At high temperatures where the hydrogen bonds in the base fluid are substantially weaker, viscosity of ZnO–PG dispersions is higher than that of PG. An estimated 80 and 37 % enhancement in heat transfer coefficient can be achieved using 2 vol% ZnO–PG nanofluid at temperatures of 10 and 28 °C, respectively.