Voltammetric determination of melatonin in tablet dosage forms and human serum

The electrochemical oxidation of melatonin is studied in Britton-Robinson buffer in the pH range 2.2-11.8 by cyclic voltammetry at glassy carbon electrode. Three irreversible, diffusion-controlled oxidation peaks were obtained. The utility of using differential pulse and square wave techniques for determination of melatonin was examined. Different parameters affecting the peak current were analylzed and at optimum conditions, linear calibration plots from 0.02-0.5 mM and 0.04 to 0.5 mM of melatonin were obtained applying the two techniques, respectively. The differential pulse mode was successfully applied to the determination of melatonin in commercial tablets containing about three-folds of vitamin B6 without previous separation. The same technique was also used for melatonin determination in human serum with acceptable accuracy.Colegio de Farmacéuticos de la Provincia de Buenos Aire

PLGA NANOPARTICLES LOADED MUCOADHESIVE AND THERMOSENSITIVE HYDROGEL AS A POTENTIAL PLATFORM FOR THE TREATMENT OF ORAL MUCOSITIS

Objective: The objective of this study was to design an effective topical treatment for oral mucositis.Methods: Poly-(DL-lactide-co-glycolide) (PLGA) nanoparticles (NPs) and Poloxamer407 (PLX)/Hydroxy propyl methyl cellulose (HPMC) hydrogel matrix (HG) were used as combined carriers for benzydamine HCL (BNZ). BNZ loaded PLGA nanoparticles were assessed for their particle size, PDI, zeta potential and entrapment efficiency. Scanning electron microscopy, thermosensitivity study, mucoadhesion study, in vitro release and in vivo investigation were used to characterize the combined BZN loaded PLGA NPs HG.Results: Negatively charged NPs with an average diameter of 139±4.92 nm were incorporated into PLX/HPMC HG bases. The gelation temperature of BZN-PLGA-NPs-HGs ranged between 31°C and 36.5°C. When diluted with saliva simulated fluid, BZN-PLGA-NPs-HGs preserved their gelation properties. Mucoadhesion was found lower for formulations prepared with PLX without HPMC. An increase in the concentrations of PLX from 10 to 30% resulted in an increase in adhesion. Both PLGA-NPs and PLGA-NPs-HG provided a biphasic drug release profile while BZN-HG provided monophasic zero order release pattern. The in vivo study showed that animal groups treated with BZN-HG and BZN-PLGA-NPs-HG showed a significantly higher reduction percentage in ulcer surface area compared to those treated with BZN-PLGA-NPs. BZN-PLGA-NPs-HG group needed 10 d of treatment to complete healing versus 16 d, 14 d and 12 d for the complete healing of groups with no treatment, treated with BZN-PLGA-NPs and treated with BZN-HG, respectively.Conclusion: BZN-PLGA-NPs-HG could represent a promising mean for the effective treatment of oral mucositis induced by cancer therapy

Voltammetric determination of melatonin in tablet dosage forms and human serum

The electrochemical oxidation of melatonin is studied in Britton-Robinson buffer in the pH range 2.2-11.8 by cyclic voltammetry at glassy carbon electrode. Three irreversible, diffusion-controlled oxidation peaks were obtained. The utility of using differential pulse and square wave techniques for determination of melatonin was examined. Different parameters affecting the peak current were analylzed and at optimum conditions, linear calibration plots from 0.02-0.5 mM and 0.04 to 0.5 mM of melatonin were obtained applying the two techniques, respectively. The differential pulse mode was successfully applied to the determination of melatonin in commercial tablets containing about three-folds of vitamin B6 without previous separation. The same technique was also used for melatonin determination in human serum with acceptable accuracy.Colegio de Farmacéuticos de la Provincia de Buenos Aire

Stabilization of active acetylene by-product via sequestration of co\u3csub\u3e2\u3c/sub\u3e

© 2020 Taylor & Francis Group, London, UK. The rising rates of carbide lime waste (CLW), the by-product of acetylene production, cause environmental problems and need for the repurposing of the said material. The high content of calcium in such by-products (60–80%) is the main reason for its utilization in CO2 sequestration. This study focused on using of CLW to form simple, reliable, cost-efficient process, applying direct solid-liquid-gas carbonation reaction, which consists of bubbling CO2 gas through an aqueous slurry of slaked CLW with different solid /water ratios. The experimental conditions were adjusted for maximum carbonation efficiency. Experimental results indicated that CLW has the potential to store CO2 in the form of stable carbonates. Considering the total calcium content, an amount of 0.5833 kg CO2 /kg CLW was achieved. The influence of solid/water ratio on the precipitation of calcium carbonate was investigated using SEM that showed a difference in crystal carbonate sizes and morphologies

Single Photon Quantum Ranging: When Sequential Decoding Meets High Dimensional Entanglement

We consider the quantum ranging problem in the low noise level per mode and low reflectivity (high loss) regime. We focus on single photon transmission strategies and propose a novel approach that combines high dimensional time-bin entanglement at the transmitter with a carefully constructed sequential decision rule at the detector. Our analytical results establish the significant performance gains that can be leveraged from this approach in a range of operating parameters, as compared to the single photon classical approach, the two-mode squeezed vacuum ranging scheme proposed earlier, and even the block-based classical scheme. One can attribute this performance gain to 1) the ability of the high dimensional time-bin entangled signaling to offer a very fine range resolution with a single transmitted photon and 2) the ability of the sequential decision rule to minimize the average number of transmitted photon subject to a constraint on the probability of error. While our analysis is limited to the low energy/low noise regime, we conjecture that the proposed approach's superior performance extends to a wider range of scenarios which should motivate further analytical and experimental investigations.Comment: Submitted to NPJ Quantum information for peer revie

The effect of serum angiotensin II and angiotensin II type 1 receptor gene polymorphism on pediatric lupus nephritis

Background: Angiotensin II (Ang II) is found to perpetuate inflammation and visceral damage in systemic lupus erythematosus (SLE). It mediates most of its actions through Ang II receptor type I (AT1) whose gene polymorphism A1166C (CC genotype) seems to have pathogenic effects. Objective: To measure serum Ang II and the frequency of AT1 receptor CC genotype among a group of Egyptian patients with pediatric onset lupus nephritis (pLN). Methods: This is a case-control cross sectional study which included 24 patients with pLN and 24 age and sex-matched healthy subjects as controls. Clinical evaluation and routine laboratory markers for SLE patients were done. SLE disease activity index (SLEDAI) and the British Isles Lupus Assessment Group (BILAG)-2004 renal score were measured. Serum Ang II was measured by enzyme linked immunosorbent assay and detection of ATI receptor CC genotype by polymerase chain reaction were done for both patients and controls. Results: Patients had significantly higher serum Ang II than the controls (p=0.0001). The frequency of AT1 receptor CC genotype was significantly higher among patients as compared to the control group (p=0.008). Both serum Ang II and AT1 receptor CC genotype were comparable between patients with proliferative LN class III and IV and those with LN class II (p>0.05). Serum Ang II did not correlate significantly with SLEDAI or BILAG-renal score (p>0.05). Conclusion: Serum Ang II and AT1 receptor CC genotype seem to have pathogenic role in pLN but with no deleterious effects on the phenotype of LN for further assessment.Keywords: Lupus nephritis; Angiotensin II; Angiotensin II type 1 receptor; Polymorphism; Pediatrics

Residual and Past Entropies of Concomitants from Lai And Xie Extensions of Case-II of Generalized Order Statistics and its Dual

In this article, we consider a new extensions of Morgenstern family is Lai and Xie extensions and discuss their concomitants for case-II of generalized order statistics and case-II of dual generalized order statistics. Additionally, recurrence relation between moments is found for the recommended models. We have also derived the expression for the joint distribution of concomitants for case-II of generalized order statistics and its dual. The residual and past entropies are shown last

Optimiranje fizikalno-kemijskih parametara, djelomično pročišćavanje i karakterizacija izvanstanične alkalne lipaze iz novog soja plijesni Curvularia sp. DHE 5

Thirty isolated fungal strains were screened for lipase production using Phenol Red plates, containing tributyrin as lipidic substrate, and a novel fungus identified genetically as Curvularia sp. DHE 5 was found as the most prominent strain. Various agro-industrial substrates were evaluated as inert supports for lipase production in solid-state fermentation. The highest yield of lipase ((83.4±2.2) U/g on dry mass basis) was reported with wheat bran medium after seven days of fermentation at pH=7.0, temperature of 30 °C, 70 % moisture content, inoculum size of 1.27·107 spore/mL and 2 % olive oil as an inducer. Supplementation of the medium with 0.05 % KCl as an ion source further increased lipase production to (88.9±1.2) U/g on dry mass basis. The enzyme was partially purified through ammonium sulphate fractionation (40 %) followed by dialysis, and its optimum pH and temperature were reported at 8.0 and 50 °C, respectively, with remarkable pH and thermal stability.U radu je ispitana proizvodnja lipaze iz 30 izolata plijesni na podlozi s tributirinom pomoću fenolnog crvenila, pri čemu se najviše istaknuo izolat koji je genetički identificiran kao novi soj plijesni Curvularia sp. DHE 5. Ispitana je mogućnost korištenja različitog agroindustrijskog otpada kao inertnih podloga za proizvodnju lipaze fermentacijom na čvrstoj podlozi. Najveći prinos lipaze od (83,4±2,2) jedinica po gramu suhe tvari dobiven je u podlozi s pšeničnim mekinjama nakon sedam dana fermentacije pri pH-vrijednosti od 7,0; temperaturi od 30 °C, 70 %-tnom udjelu vlage, veličini inokuluma od 1,27·107 spora po mililitru i s dodatkom 2 %-tnog maslinovog ulja. Dodatak 0,05 % KCl kao izvora iona dodatno je potaknuo proizvodnju lipaze na 88,9±1,2 jedinica po gramu suhe tvari. Enzim je djelomično pročišćen (40 %) frakcioniranjem pomoću amonijeva sulfata i dijalizom, te se pokazao izuzetno stabilinim, s optimalnom pH-vrijednosti od 8,0 i optimalnom temperaturom od 50 °C