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In this study, five earth-friendly spectrophotometric methods using multivariate techniques were developed to analyze levofloxacin, linezolid, and meropenem, which are utilized in critical care units as combination therapies. These techniques were used to determine the mentioned medications in laboratory-prepared mixtures, pharmaceutical products and spiked human plasma that had not been separated before handling. These methods were named classical least squares (CLS), principal component regression (PCR), partial least squares (PLS), genetic algorithm partial least squares (GA-PLS), and artificial neural network (ANN). The methods used a five-level, three-factor experimental design to make different concentrations of the antibiotics mentioned (based on how much of them are found in the plasma of critical care patients and their linearity ranges). The approaches used for levofloxacin, linezolid, and meropenem were in the ranges of 3-15, 8-20, and 5-25 µg/mL, respectively. Several analytical tools were used to test the proposed methods' performance. These included the root mean square error of prediction, the root mean square error of cross-validation, percentage recoveries, standard deviations, and correlation coefficients. The outcome was highly satisfactory. The study found that the root mean square errors of prediction for levofloxacin were 0.090, 0.079, 0.065, 0.027, and 0.001 for the CLS, PCR, PLS, GA-PLS, and ANN models, respectively. The corresponding values for linezolid were 0.127, 0.122, 0.108, 0.05, and 0.114, respectively. For meropenem, the values were 0.230, 0.222, 0.179, 0.097, and 0.099 for the same models, respectively. These results indicate that the developed models were highly accurate and precise. This study compared the efficiency of artificial neural networks and classical chemometric models in enhancing spectral data selectivity for quickly identifying three antimicrobials. The results from these five models were subjected to statistical analysis and compared with each other and with the previously published ones. Finally, the whiteness of the methods was assessed by the recently published white analytical chemistry (WAC) RGB 12, and the greenness of the proposed methods was assessed using AGREE, GAPI, NEMI, Raynie and Driver, and eco-scale, which showed that the suggested approaches had the least negative environmental impact. Furthermore, to demonstrate solvent sustainability, a greenness index using a spider chart methodology was employed., 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 Elsevier B.V. All rights reserved.)

This study introduces a new method for analyzing rifampicin, moxifloxacin, and metronidazole using a green micellar High Performance Liquid Chromatography-Ultraviolet method in bulk drugs, different commercial formulations, and spiked human plasma. The combined therapy of these three broad-spectrum antibiotics is used to cure refractory hidradenitis suppurativa (HS), an inflammatory condition affecting the skin. The sustainable separation was attained on a reversed-phase C18 Kinetex® column maintained at ambient temperature in less than 5 min. The mobile phase comprises 0.1 M sodium dodecyl sulfate (SDS) in water, pH 3.5, adjusted using o-phosphoric acid, and 10% n-butanol. The flow rate was 1 mL/min, with 10 μL injection volume and UV detection at 230 nm. The impact of three key significant variables, SDS concentration, n-butanol percentage, and the mobile phase pH, on suitability parameters was studied. ICH and FDA guidelines were committed to when validating the technique. The results showed linear calibration graphs with high precision and accuracy, in both pure and spiked plasma. The method is efficient, easy to use, and has a high sample throughput, making it suitable for routine analysis in the quality control department and therapeutic monitoring. It is also evaluated as a green-and-white substitute for traditional reported methods., (© 2023 Deutsche Pharmazeutische Gesellschaft.)

It is crucial to have a reliable and sensitive method for separating common drugs used in SARS-CoV-2 pneumonia treatment protocols for ongoing treatment and upcoming investigations. This study presents an HPLC-FLD approach to analyze three co-administered medicines - remdesivir (RDV), hydroxychloroquine sulphate (HCQ), and levofloxacin hemihydrate (LVX) - in their pure forms, pharmaceutical preparations, and spiked human plasma. The HPLC-FLD analysis was conducted using a Symmetry® C18 column (100 mm × 4.6 mm ID, 3.5 μm particle size) at 40 °C, with (A) an aqueous mixture of 0.02 M phosphate buffer and 0.2% heptane-1-sulphonic acid sodium solutions (50 : 50) adjusted to pH 3, (B) acetonitrile, and (C) methanol as the mobile phase. The injection volume was 10 μL, and the flow rate was 1.5 mL min -1 . The detection was done using a multi-wavelength excitation and emission fluorescence detector, with individual optimization for each drug. The drug separation time was less than 10 minutes, and the method showed sensitive and wide linearity ranges for all medicines, with r 2 values of more than 0.999. The impact of the mobile phase pH and flow rate on suitability parameters (retention time and number of theoretical plates) was studied. The method was found to be environmentally friendly based on GAPI and AGREE metrics. The validity of the method was evaluated following ICH and FDA guidelines.

Testing and treating asymptomatic populations have the potential to reduce the population's parasite reservoir and reduce malaria transmission. Zanzibar's malaria case notification (MCN) platform collects detailed sociodemographic and epidemiological data from all confirmed malaria cases to inform programmatic decision-making. We describe the design and operationalization process of the platform and other malaria surveillance resources that are enabling Zanzibar's progress toward malaria elimination.The MCN platform consists of an interactive short message service (SMS) system for case notification, a software application for Android mobile devices, a visual question set and workflow manager, a back-end database server, and a web browser-based application for data analytics, configuration, and management. Malaria case data were collected from August 2012 to December 2021 and reported via SMS from all public and private health facilities to a central database and then to district malaria surveillance officers' mobile devices. Data included patient names, shehia (administrative area), and date of diagnosis, enabling officers to track patients, ideally within 24 hours of reporting. Patients' household members were tested for malaria using conventional rapid diagnostic tests (RDTs). Treatment using artemisinin-based combination therapy was provided for persons testing positive.Between 2012 and 2021, a total of 48,899 index malaria cases were confirmed at health facilities, 22,152 (45.3%) within 24 hours of reporting; 41,886 (85.7%) cases were fully investigated and followed up to the household level. A total of 111,811 additional household members were tested with RDTs, of whom 10,602 (9.5%) were malaria positive.The MCN platform reports malaria case data in near real time, enabling prompt follow-up of index cases and prompt testing and treatment of members in index case households. Along with routine testing and treatment and other preventive interventions, the MCN platform is foundational to the programmatic efforts in further reducing malaria and ultimately eliminating autochthonous malaria transmission in Zanzibar., (© Mkali et al.)

A novel, sensitive, and green micellar UPLC method was proposed and validated for the simultaneous determination of four hypoglycemic agents used in type II diabetes mellitus treatment namely, pioglitazone, alogliptin, glimepiride, and vildagliptin. The developed UPLC method was successfully applied for quantitative analysis of these drugs in bulk, in pharmaceutical formulations, and in spiked human plasma. Chromatographic separation was carried out on a Kinetex® 1.7 μm XB-C18 100 Å (50 × 2.1 mm) column, using a degassed and filtered mixture of (0.1 M SDS- 0.3% triethyl amine- 0.1% phosphoric acid (pH 6)) and n-propanol (85:15 v/v), at a flow rate of 0.2 mL/min. The experimental conditions of the suggested method were well investigated and optimized. The newly developed micellar UPLC method is capable of determining different dosage forms at the same time with the same solvents, saving time and effort. The method was found to be efficiently applicable in spiked human plasma and could be extended to study the pharmacokinetics of the cited drugs in real human plasma samples. The greenness of the developed method was evaluated by applying the Eco-scale scoring tool, which verified the excellent greenness of the analytical method., (© 2023. The Author(s).)

Background: Daclatasvir dihydrochloride has important roles not only in the management of COVID-19 pandemic symptoms but also in the treatment of chronic hepatitis C infection., Objective: The current research presents four novel and simple platforms including silver-nanoparticles spectrophotometric technique and three electrochemical conductometric ones for daclatasvir analysis in its tablet, biological fluids, and dissolution media., Methods: The spectrophotometric platform involved the synthesis of silvernanoparticles through a redox reaction between the reducing agent (daclatasvir) and the oxidizing agent (silver nitrate) in presence of polyvinylpyrrolidone as a stabilizing agent. The produced silver-nanoparticles have an intense surface plasmon resonance peak at 421 nm where the measured absorbance values were utilized for quantitative spectrophotometric determination of daclatasvir. While the electrochemical conductometric platforms involved the reaction of daclatasvir with three different precipitating reagents (silver nitrate, phosphomolybdic acid, and ammonium reineckate) to form ion associates between these reagents and daclatasvir in the aqueous system., Results: All proposed platforms were validated in line with recommendations of the international conference on harmonization producing satisfactory outcomes within the agreed boundaries., Conclusion: The proposed platforms are green alternatives for routine rapid assay of daclatasvir at the cheapest cost because their results were observed to be nearly similar to those of the reported platform. Moreover, the suggested spectrophotometric platform's sensitivity can be employed for investigating daclatasvir bioequivalence., (© 2023. The Author(s).)

Background: Oral anti-platelet agents are the cornerstone of the treatment of multiple cardiovascular diseases and in the long-term prevention of their recurrence., Objective: In the present work, we report a method based on micellar liquid chromatography coupled with ultraviolet detection (MLC/UV), for the simultaneous quantification of combined anti-platelet therapy namely, clopidogrel bisulfate (CPS), aspirin (ASP), together with salicylic acid (SA), in their pharmaceutical dosage form., Methods: The incorporation of 0.1M polyoxyethylene 23 lauryl ether (Brij-35) as a surfactant into the mobile phase improved solute-mobile phase interaction allowing for minimal organic solvent utilization, enhanced resolution, and rapid analysis (7 min). Furthermore, we performed a comprehensive evaluation of the environmental impact caused by our procedures versus previously reported analytical procedures applied in the determination of CPS and ASP. The evaluation was made using the Eco-scale tool., Results: The results of the developed method indicated the superiority of our procedures in terms of greenness without compromising the quality of performance characteristics. The method was linear in the range of 1-100 µg/mL with limits of detection of 0.28, 0.32, and 0.29 µg/mL for CPS, ASP, and SA, respectively. The developed method can also be utilized to test the purity and the stability of ASP in pharmaceutical formulations through monitoring SA as its main degradation product., Conclusion: The MLC/UV method was successfully applied to the quantitative analysis of CPS, ASP together with SA-as a main degradation product of ASP-in their pharmaceutical dosage form., Highlights: The developed method was successfully applied for the determination of clopidogrel bisulfate (CPS), aspirin (ASP), together with salicylic acid (SA), in their pharmaceutical dosage form., (© The Author(s) 2022. Published by Oxford University Press on behalf of AOAC INTERNATIONAL. All rights reserved. For permissions, please email: journals.permissions@oup.com.)

Aspirin and omeprazole combining has proven their effectiveness clinically in the treatment and prevention of cardiovascular diseases in patient with gastric diseases and gastric ulcers. Simultaneous determination of omeprazole and aspirin in their combination is a challenge due to the overlapping spectra of these drugs. Six smart and different spectrophotometric methods were developed for the analysis of omeprazole and aspirin in binary mixture and pharmaceutical dosage form. These smart methods characterized by simplicity and accuracy. The first two methods based on minimal mathematical data processing based on the zero order absorption spectra were; dual wavelength and advanced absorbance subtraction methods. The third method is first and second derivative spectrophotometric method that based on derivative spectra. The last three methods based on ratio spectra manipulation are named; ratio difference, mean centering and derivative ratio spectrophotometric methods. The linearity range of omeprazole was 2-20 μg/mL for dual wavelength method and 2-30 μg/mL for the other ones, while aspirin showed a good linearity over a range of 2.5-30 μg/mL for all methods. The correlation coefficients were greater than 0.999. The results of the developed methods are statistically compared with each other and with the results of the reported HPLC method showing no significant difference. The greenness of the developed methods was assessed using eco-scale scoring method revealing excellent greenness of the applied methods. This spectrophotometric methods is more sensitive and greener with comparing by the reported one so, these developed methods are considered eco-friendly to the environment., 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 © 2021 Elsevier B.V. All rights reserved.)

Background: A recent combination of aspirin (ASP) and omeprazole (OMP) has been presented in a fixed dosage form for the treatment of many cardiovascular diseases, particularly in patients with gastric diseases. However, ASP is very sensitive to degradation into salicylic acid (SAL) as its main degradation product. Hence, it is very important to develop methods for the determination of ASP and OMP in the presence of SAL., Objective: In this study, UV spectrophotometry assisted by different univariate/multivariate post processing algorithms is presented for quantitative determination of ASP, OMP, and SAL without any prior separation., Methods: The univariate/multivariate algorithms include double divisor ratio difference and double divisor mean centering as the univariate approaches while the multivariate methods include principal component regression (PCR) and partial least squares (PLS) models. Validation of the univariate methods was done according to International Conference on Harmonization guidelines, while the multivariate models were validated using an external validation set., Results: The univariate algorithms displayed excellent regression and validation capabilities in terms of linearity, accuracy, precision, and selectivity. Regarding PCR and PLS, the number of latent variables were carefully optimized, and the model's validation criteria displayed excellent recoveries and lower errors of prediction., Conclusion: Our findings indicate that the developed methods were comparable to the reported chromatographic methods, but are simpler and have much shorter analysis times., Highlights: Overall, this report presents the first spectrophotometric methods applied for determination of possible combinations of ASP, OMP, and SAL, and poses these methods as valuable analytical tools for in-process testing and quality control analysis., (© AOAC INTERNATIONAL 2021. All rights reserved. For permissions, please email: journals.permissions@oup.com.)

Background: Over the past two decades, Zanzibar substantially reduced malaria burden. As malaria decreases, sustainable improvements in control interventions may increasingly depend on accurate knowledge of malaria risk factors to further target interventions. This study aimed to investigate the risk factors associated with malaria infection in Zanzibar., Methods: Surveillance data from Zanzibar's Malaria Case Notification system from August 2012 and December 2019 were analyzed. This system collects data on malaria cases passively detected and reported by all health facilities (index cases), and household-based reactive case detection (RCD) activities linked to those primary cases. All members of households of the index cases were screened for malaria using a malaria rapid diagnostic test (RDT). Individuals with a positive RDT were treated with artemisinin-based combination therapy. Univariate and multivariate logistic regression analyses were done to investigate the association between RDT positivity among the household members and explanatory factors with adjustment for seasonality and clustering at Shehia level., Results: A total of 30,647 cases were reported of whom household RCD was completed for 21,443 (63%) index case households and 85,318 household members tested for malaria. The findings show that younger age (p-value for trend [Ptrend] < 0.001), history of fever in the last 2 weeks (odds ratio [OR] = 35.7; 95% CI 32.3-39.5), travel outside Zanzibar in the last 30 days (OR = 2.5; 95% CI 2.3-2.8) and living in Unguja (OR = 1.2; 95% CI 1.0-1.5) were independently associated with increased odds of RDT positivity. In contrast, male gender (OR=0.8; 95% CI 0.7-0.9), sleeping under an LLIN the previous night (OR = 0.9; 95% CI 0.7-0.9), having higher household net access (Ptrend < 0.001), and living in a household that received IRS in the last 12 months (OR = 0.8; 95% CI 0.7-0.9) were independently associated with reduced odds of RDT positivity. A significant effect modification of combining IRS and LLIN was also noted (OR = 0.7; 95% CI 0.6-0.8)., Conclusions: The findings suggest that vector control remains an important malaria prevention intervention: they underscore the need to maintain universal access to LLINs, the persistent promotion of LLIN use, and application of IRS. Additionally, enhanced behavioural change and preventive strategies targeting children aged 5-14 years and travellers are needed., (© 2021. The Author(s).)

Miconazole nitrate (MIC) and nystatin (NYS) combination has proven its effectiveness as a prodigious therapy to cure women's common infections; vaginal candidiasis and vaginal mycosis. Herein, six smart UV-spectrophotometric platforms depending on minimal mathematical manipulation steps were first introduced for the simultaneous green analysis of MIC and NYS in their pure forms and commercial vaginal suppositories without any preliminary separation steps. These platforms included dual-wavelength, ratio difference, mean centering of ratio spectra, first derivative ratio, ratio subtraction, and absorption correction methods. All of the aforementioned platforms could estimate MIC in a linear range of 90-900 µg/ml. While NYS was computed directly by zero-order spectrophotometry at its λ max (304 nm) in a linear range of 1-15 µg/ml without any interference by MIC even in low or high concentrations. Dual-wavelength and zero-order spectrophotometric platforms were successfully applied to study the dissolution profile of MIC and NYS in their combined formulation in compliance with FDA recommendations without excipients interference. According to ICH guidelines, all platforms were validated regarding the accuracy, precision, and selectivity producing satisfactory results within the accepted limits. Also, the suggested platforms' results were statistically compared with each other and with those of the reported HPLC platform revealing no significant difference concerning accuracy and precision at p  = .05. Accordingly, all proposed platforms are regarded as economic and eco-friendly alternatives to the expensive chromatographic platforms that utilize hazardous organic solvents during the analysis of cited drugs.

Competing Interests: Declaration of competing interest The authors have no conflict of interest.

A new and simple spectrophotometric method was developed for the simultaneous determination of a new antidiabetic mixture of linagliptin and empagliflozin namely fourier self deconvulated method. The developed method based on minimal mathematical data processing on the zero order spectrum for solving sever overlapping spectra of the mentioned drugs in their pure forms and pharmaceutical dosage form. The zero order spectra of linagliptin and empagliflozin were deconvulated using Fourier transforms function. The peak amplitudes at 232 nm were selected for linagliptin and at 239 nm for empagliflozin. The constructed calibration graphs were linear over the range (5-30 µg/mL) and (2-12 µg/mL) for empagliflozin and linagliptin, respectively. The adopted method was simple, accurate, precise and validated according to the ICH guidelines., 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 © 2021 Elsevier B.V. All rights reserved.)

Flumethasone pivalate (FP) and clioquinol (CL) formulation was developed as a prodigious remedy to cure the external ear inflammatory disorders. So, the current research introduces five smart and novel UV-spectrophotometric platforms relying on minimal mathematical manipulation steps for simultaneous green analysis of FP and CL with no preliminary separation in their formulation that suffered from the high difference of their ratio and severe spectral overlapping. These platforms involved dual-wavelength, first derivative ratio, Fourier self-deconvolution, area under the curve, and bivariate methods. The suggested platform' linearity was observed over the concentration range of 3-42 µg/ml for FP and 1.5-8 µg/ml for CL. All suggested platforms were validated according to ICH recommendations regarding accuracy, precision, repeatability, and selectivity producing satisfactory results within the accepted limits. These platforms were represented as rapid, green, and cheap alternatives to the reported chromatographic method due to lower solvent consumption and waste generation. Furthermore, they improved the determination sensitivity of the studied drugs and enhanced the recorded data signals or its spectral resolution by the newly introduced Fourier self-deconvoluted method. The statistical comparison between the results of the suggested platforms with each other and with those of the reported method showed no significant differences between them.

Empagliflozin and linagliptin are newly approved FDA combination that used for the treatment of type 2 diabetes mellitus (T2DM) under trade name Glxambi. Two spectroflourimetric methods were developed for simple quantitative determination of empagliflozin and linagliptin in their pharmaceutical formulation and human plasma without need any tedious processing operations. Empagliflozin has a native fluorescence nature, therefore can be directly determined by measuring emission peak at 305 nm after excitation at 234 nm. There is no any interference from linagliptin at this emission wavelength. On the other hand, linagliptin is a very weak florescent compound that needs to react with fluorogenic reagent to be quantitatively determined without any reaction of empagliflozin. So, quantitative analysis of linagliptin was achieved by coupling with NBD-Cl which is an electro active halide reagent (targeting only Linagliptin with no effect on empagliflozin). Dark yellow fluorophore with high fluorescence is a result of this reaction and can be measured at emission wavelength 538 nm after excition at wavelength 469 nm. Experimental conditions of the suggested methods were well checked and optimized. The regression plots were found to be linear over the range of 40-1200 ng/mL and 3-700 ng/mL for empagliflozin and linagliptin, respectively. The obtained results by the suggested methods were statistically compared with those obtained by the reported methods, showing no significant difference with respect to accuracy and precision at p = 0.05., 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 © 2020 Elsevier B.V. All rights reserved.)

This study is the first to develop and optimize a method for the simultaneous determination of chlorthalidone (CLT) and telmisartan (TEL) in, human plasma samples as well as in their newly released pharmaceutical tablet form, (Telmikind-CT 40®). The method is based on measuring fluorescence intensity, employing synchronous fluorescence mode coupled to third-order derivative signal processing, 0.5% w/v cetyl trimethyl ammonium bromide was used as cationic surfactant to enhance the fluorescence signal intensity and improve method sensitivity. The third-order derivative synchronous spectra of CLT and TEL are well separated with two zero-crossing points which allowed for the determination of CLT and TEL at 362 nm and 351 nm, respectively. Different experimental parameters were carefully investigated and optimized, calibration curves were constructed over concentration ranges of 20-1200 ng.mL -1 and 5-800 ng.mL -1 for CLT and TEL respectively. The developed method is simple and rapid, analytical parameters were validated according to ICH guidelines and high sensitivity was achieved as represented by limits of detection (LOD) of 4.69 and 1.58 ng.mL -1 for CLT and TEL respectively.

A suitable HPLC method has been selected and validated for rapid simultaneous separation and determination of four imidazole anti-infective drugs, secnidazole, omeprazole, albendazole, and fenbendazole, in their final dosage forms, in addition to human plasma within 5 min. The method suitability was derived from the superiority of using the environmentally benign solvent, methanol over acetonitrile as a mobile phase component in respect of safety issues and migration times. Separation of the four anti-infective drugs was performed on a Thermo Scientific ® BDS Hypersil C 8 column (5 µm, 2.50 × 4.60 mm) using a mobile phase consist of MeOH: 0.025 M KH 2 PO 4 (70:30, v/v ) adjusted to pH 3.20 with ortho-phosphoric acid at room temperature. The flow rate was 1.00 mL/min and maximum absorption was measured with UV detector set at 300 nm. Limits of detection were reported to be 0.41, 0.13, 0.18, and 0.15 µg/mL for secnidazole, omeprazole, albendazole, and fenbendazole, respectively, showing a high degree of the method sensitivity. The method of analysis was validated according to Food and Drug Administration (FDA)guidelines for the determination of the drugs, either in their dosage forms with highly precise recoveries, or clinically in human plasma, especially regarding pharmacokinetic and bioequivalence studies.

Herein, UV spectrophotometry assisted by multivariate chemometric analysis have been presented for quantitative determination of complex quinary therapy containing atenolol, ramipril, hydrochlorothiazide, simvastatin and aspirin without any prior separation. Such combination is very useful for treating various cardiovascular diseases (CVD) including high blood pressure, hypercholesterolemia in addition to its antiplatelet aggregating activity. Calibration (15 samples) and validation (10 samples) sets were prepared of different concentrations for these drugs via implementing partial factorial experimental design. The zero order UV spectra of these sets were recorded and then subjected for further chemometric analysis. Partial least square (PLS) with/without variable selection procedure i.e. genetic algorithm (GA) were employed to untangle the UV spectral overlapping of these mixtures. The performance of these chemometric techniques were compared in terms of accuracy and predictive abilities using cross-validation and external validation methods. It was found that PLS provides good recoveries with prompt predictive ability albeit GA-PLS exhibited better analytical performance owing to its capability to remove redundant variables i.e. the number of absorbance variables had been reduced to about 19-28%. The developed methods allowed reliable determination of such complex therapy in its laboratory prepared mixtures and pharmaceutical preparation within comparable results to those reported by HPLC method, posing these chemometric methods as valuable and indispensable analytical tools in in-process testing and quality control analysis of many pharmaceutical compounds targeting CVD., 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 © 2020 Elsevier B.V. All rights reserved.)

Counterfeit drugs have adverse effects on public health; chromatographic methods can be used but they are costly. In this study, we developed cost-effective and environmentally friendly methodology for the analysis of terazosin HCl (TZ) in the presence prazosin hydrochloride (PZ) using UV spectroscopy in conjunction with machine learning (ML) models. Variable selection algorithms were applied to select most informative spectral variables. Thirty-five ML models were assessed and their performances were compared. The models covered a wide range of prediction mechanisms, such as tree-based, linear, self-organizing maps, neural network, Gaussian process, boosting, bagging, Bayesian models, kernel methods, and quantile regression. The values of the root mean square error (RMSE), coefficient of determination (R 2 ), and absolute mean error (MAE) were obtained for the evaluation of the developed models. According to the results of these performance indices, linear model showed the highest prediction capacity among all other models. RMSE, R 2 and MAE values of (0.159, 0.997 and 0.131) and (0.196, 0.99 and 0.161) were obtained for train and test datasets, respectively. The predictive models in this study can be useful for the researchers who are interested to work on the determination of active ingredients in pharmaceutical dosage forms in the presence of interference using UV spectroscopy; therefore, it was used to determine TZ without interference of PZ., 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., (Crown Copyright © 2020. Published by Elsevier B.V. All rights reserved.)

Colloidal particles based on supramolecular polymers are emerging as promising functional materials because of their intrinsic dynamic features and the possibility of stimuli responsivity. In this work, ≈200 nm self-assembled redox-responsive colloidal particles made of 1D-coordination polymers were readily prepared. In these metallopolymers, organic entities made of bis(viologen) groups covalently associated with terpyridine units are spontaneously bridged by Zn 2+ cations through the formation of coordination bonds. The properties of these particles were analyzed and their redox activities investigated. Upon reduction of the viologen units, the formation of π-dimers between the reduced viologen moieties was demonstrated by spectroscopic experiments. It was shown that intermolecular π-dimers (i.e., between different polymer chains) that do not exist in homogeneous polymer solutions were, nevertheless, formed in the particle's structure because of the effects of confinement. The presence of these π-dimers allows stabilization of the charge in the colloids.

Objectives: In the present study, an eco- friendly micellar liquid chromatographic technique was validated for separation and quantification of two drugs; namely ribavirin (RIV), and sofosbuvir (SBV) in pure form, pharmaceuticals containing them, human plasma and human urine. These drugs are administered co-administered for treatment of Hepatitis C virus (HCV) that causes hepatitis C in humans., Material and Methods: These drugs were separated using Nucleosil 100-5 phenyl column. Sodium dodecyl sulphate (SDS) solution (0.05M, pH 7.0) containing triethylamine (0.3%) and n-butanol (10%) was used as a mobile phase with 1.2 mLmin -1 flow rate and 215nm detection wavelength. Nine minutes were required for resolving the two drugs from the matrix., Results: The method showed good linearity for RIV and SBV with correlation coefficients (r 2 ) more than 0.9996 within the concentration ranges of (20-400) and (40-400) ngmL -1 in pure form, (30-300) and (50-300) ngmL -1 in human plasma and (20-400) and (40-400) ngmL -1 in human urine, respectively., Conclusion: The recommended method was applied for examination of RIV and SBV in pure and pharmaceuticals. The obtained results were statistically matched with reported methods with no significant differences. Also, the recommended method was effectively applied for estimation of both drugs in spiked human urine and plasma without purification or extraction steps and real samples of plasma and urine of humans having therapy of RIV and SBV, as well as, performing tablets dissolution-rate tests with satisfactory results., (Copyright © 2020 Académie Nationale de Pharmacie. Published by Elsevier Masson SAS. All rights reserved.)

Aim: To develop simple and rapid UV-spectrophotometric platforms for the simultaneous quantification of a binary mixture containing clopidogrel bisulphate (CPS) and aspirin (ASP) in complex matrices without prior separation. Experimental: Five mathematical models namely ratio-difference method, mean centering of the ratio spectra, dual wavelength, induced dual wavelength and H-Point Standard Addition method, were utilized for resolving spectral overlap by mathematical processing of ratio and zero-order absorption spectra. Analytes were extracted from tested matrices (whole blood, pharmaceutical formulations and dissolution media buffer) and quantified using the proposed methods. The methods were validated according to ICH guidelines. Results: The developed methods demonstrated limits of detection ranging from 0.67 to 1.09 μg/ml -1 for CPS and 0.49 to 0.71 μg.ml -1 for ASP. All proposed methods allowed for reliable determination of CPS and ASP in complex matrices within reported reference ranges, indicating their potential application for therapeutic drug monitoring and quality control testing.

Lyme disease (LD) accounts for over 70% of tick-borne disease reported in the United States. The disease in humans is characterized by skin rash, arthritis, cardiac and neurological signs. Vaccination is the most efficient preventive measure that could be taken to reduce the incidence of the LD worldwide; however, at present no vaccine is available. In this study, evaluation of the Borrelia burgdorferi BB0172-derived peptide (PepB) in conjugated formulations was investigated as a vaccine candidate in murine model of LD. In brief, PepB was conjugated to the Cross-Reacting Material 197 (CRM197) and to Tetanus Toxoid heavy chain (TTHc) molecules, and subsequently used to immunize C3H/HeN mice. Following the challenge with 10 5 spirochetes/mouse via subcutaneous inoculation, TTHc:PepB construct showed protection in 66% of the immunized animals. Hence, to further evaluate the efficacy of TTHc:PepB, immunized mice were challenged with B. burgdorferi using the tick model of infection. The outcome of this experiment revealed that serum from TTHc:PepB immunized mice was borrelicidal. After tick infection, bacterial burden was significantly reduced (over 70%) in vaccinated animals when compared with the control groups regardless of whether the mice were infested 8 or 12-weeks post-priming. Therefore, we conclude that PepB conjugated antigens can serve as an alternative to prevent LD; nevertheless, further studies will be needed to dissect the mechanisms by which anti-PepB IgG antibodies are able to kill B. burgdorferi in vitro and in vivo to further advance in the development of formulations and delivery alternative to generate a safe anti-LD vaccine., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

A high performance liquid chromatography method had been developed and validated for rapid simultaneous separation and determination of three anti-helicobacter drugs, oxytetracycline (OXY), tinidazole (TIN) and esomeprazole (ESM) in human plasma within 6 minutes. Drugs extraction method from plasma was based on protein precipitation technique. Separation was carried out on a Equisil BDS C18 column (5 μm, 150 × 4.60 mm) using a mobile phase of acetonitrile: 0.025 M KH2PO4 (25: 75, v/v) adjusted to pH 3.50 with ortho-phosphoric acid at ambient temperature. The flow rate was 1 mL/min and maximum absorption was measured using Diode Array (DAD) detector at 285 nm. The retention times of OXY, TIN and ESM were recorded to be 2.68, 3.52 and 5.17 minutes, respectively, indicating a shorter analysis time. Limits of detection were also reported to be 0.10, 0.07 and 0.04 μg/mL for OXY, TIN and ESM, respectively, showing a high degree of the method sensitivity. The method was then validated according to FDA guidelines for the determination of the drugs clinically in human plasma specially regarding pharmacokinetic and bioequivalence studies., (© The Author(s) 2019. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)

Novel univariate and multivariate factor-based calibration-prediction techniques were validated for simultaneous ultraviolet spectrophotometric determination of ribavirin (RIV), daclatasvir (DAV), sofosbuvir (SOV), and sorafenib (SON) which are co-administered for treatment of hepatocellular carcinoma (HCC) that results from Hepatitis C-virus (HCV) infection in their commercial products and in biological fluids. Determination of these compounds is essential owing to their pharmacotherapeutic benefits. Due to spectral overlapping of RIV, DAV, SOV, and SON, univariate extended derivative ratio (EDR) method and multivariate partial least-squares (PLS) and principal component regression (PCR) methods were used for constructing the calibration curves. The extended derivative ratio (EDR) absorption maxima at 215 nm and minima at 310.5 nm was used for determination of RIV and DAV, respectively and absorption maxima at 240.3 nm and minima at 284.5 nm for determination of SOV and SON, respectively. The linearity was established over the range of 6-42 μg mL -1 , 4-16 μg mL -1 , 10-70 μg mL -1 , and 3-9 μg mL -1 for RIV, DAV, SOV and SON with correlation coefficient (r2) of 0.9997, 0.9997, 0.9999 and 0.9997, respectively. This method was effectively applied to pure, pharmaceutical preparations and to spiked human urine and plasma. PLS and PCR models were established for the determination of the studied drugs in the range of 6-42, 4-16, 10-70 and 3-9 μg mL -1 for RIV, DAV, SOV, and SON, respectively. Furthermore, updating the PLS model (PLS model update) were allowed for the determination of these drugs in spiked human urine, plasma and drug-dissolution test of their tablets. The obtained results were compared to official and reported method showing that there were no significant differences. The results of applying PLS and PCR models for evaluation of RIV, DAV, SOV, and SON in human urine samples as real samples were also encouraging. It is expected that the suitable features of the proposed method make it helpful for biological and clinical applications., (Copyright © 2019 Elsevier B.V. All rights reserved.)

The data presented are related to the article entitled "Six Sigma quality approach for HPLC-UV method optimization" Ibrahim et al., 2019. The raw data of HPLC analysis of ascorbic acid (AS), paracetamol (PA) and guaifenesin (GU) are presented. Calibration standards were prepared at six concentrations levels (25%, 50%, 75%, 100%, 125% and 150%) each day and measured in triplicate. Validation standards were prepared at four concentration levels (25%, 60%, 100% and 150%) each day and measured in quintet. Three different series were used for method validation and prepared at the rate of one series per day.

Two simple methods were developed for determination of butoconazole nitrate (BN). The first developed method was stability-indicating HPTLC-densitometric method (method A) which is based on the quantitative densitometric separation of butoconazole nitrate (BN) from its degradation products on silica gel 60 F 254 and measurement of the bands at 290nm. The developed stability study of BN was performed under different stress conditions including oxidative, hydrolytic, thermal and photolytic. Degradation was observed under acidic hydrolytic and oxidative conditions. Moreover, the HPTLC method was used to study the kinetics of BN acid degradation, determining as first order kinetics. The degradation rate constant of BN was found to be 0.076 hr -1 and t 1/2 value was determined at 9.12 hr in acidic medium. The second method (Method B) was conductometric method which is based on the reaction of BN with phosphotungstic acid (PTA) to form an ion associate in 50% methanol-water system. Validation of the proposed methods was carried out. All proposed methods were successfully applied for the commercial dosage form of BN. Statistical analysis of the results has been carried out revealing high accuracy and good precision., (Copyright © 2018 Académie Nationale de Pharmacie. Published by Elsevier Masson SAS. All rights reserved.)

In accordance with International Conference on Harmonisation of Technical Requirements for Registration of Pharmaceuticals for Human Use (ICH) guidelines, six novel, simple and precise sequential spectrophotometric methods were developed and validated for the simultaneous analysis of Ribavirin (RIB), Sofosbuvir (SOF), and Daclatasvir (DAC) in their mixture without prior separation steps. These drugs are described as co-administered for treatment of Hepatitis C virus (HCV). HCV is the cause of hepatitis C and some cancers such as liver cancer (hepatocellular carcinoma) and lymphomas in humans. These techniques consisted of several sequential steps using zero, ratio and/or derivative spectra. DAC was first determined through direct spectrophotometry at 313.7 nm without any interference of the other two drugs while RIB and SOF can be determined after ratio subtraction through five methods; Ratio difference spectrophotometric method, successive derivative ratio method, constant center, isoabsorptive method at 238.8 nm, and mean centering of the ratio spectra (MCR) at 224 nm and 258 nm for RIB and SOF, respectively. The calibration curve is linear over the concentration ranges of (6-42), (10-70) and (4-16) μg/mL for RIB, SOF, and DAC, respectively. This method was successfully applied to commercial pharmaceutical preparation of the drugs, spiked human urine, and spiked human plasma. The above methods are very simple methods that were developed for the simultaneous determination of binary and ternary mixtures and so enhance signal-to-noise ratio. The method has been successfully applied to the simultaneous analysis of RIB, SOF, and DAC in laboratory prepared mixtures. The obtained results are statistically compared with those obtained by the official or reported methods, showing no significant difference with respect to accuracy and precision at p = 0.05., (Copyright © 2018 Elsevier B.V. All rights reserved.)

We report the study of stimuli-responsive Zn II and Fe II coordination polymers (MC3 4+ or MC2 4+ with M=Fe 2+ or Zn 2+ ). These soluble metallopolymers were formed spontaneously by reaction of an organic ligand (C3 4+ or C2 4+ ) with one molar equivalent of metal ions. The C3 4+ and C2 4+ ligands incorporate two chelating terpyridine groups bridged by a redox responsive hinge featuring two viologen units (viologen=N,N'-dialkyl-4,4'-bipyridinium) linked either with propyl (C3 4+ ) or ethyl (C2 4+ ) chains. The viologen units in the polymer chains were reduced (1 e - per viologen group) either by bulk electrolysis or by visible-light irradiation carried out in the presence of a photosensitizer. The 1 e - reduction of the viologen units in the MC2 4+ polymers induced a slight decrease in the viscosity of the solutions due to a modification of the overall charge carried by the metallopolymers. In strong contrast, reduction of coordination polymers involving propyl linkers (MC3 4+ ) led to a remarkable increase (≈+400 %) in observed viscosity. This reversible effect was attributed to a folding of the polymer chains triggered by π-dimerization of the photo-generated viologen cation radicals., (© 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

This work reports on the synthesis and characterization of a new porphyrins complex:[Zn(TEBOP)(4,4'-bpy)](4,4'-bipyridine)(5,10,15,20-(tetraethyl-4(4-butyryl)oxyphenyl)porphyrinato)zinc(ii) (3). Single crystal X-ray diffraction, photophysical and electrochemical characteristics were studied. The prepared complex, penta-coordinated zinc(ii) porphyrin derivatives shows moderate ruffling distortion and the zinc atom is nearly planar with the porphyrin core. Tolyl and ethyl-4(4-butyryl)oxyphenyl) moieties at the meso positions present a bathochromic shift of the absorption bands, and a notable increase in the absorption coefficient of the Q(0,0) and Q(0,1) bands was observed with a higher fluorescence quantum yield and lifetime compared with the free base porphyrin. The electrochemical investigation shows a reversible reduction of the synthesized complexes. The catalytic power and the adsorption properties of the prepared complexes were studied for Calmagite degradation, an azoic organic dye. The results reveal that the studied compounds could be used as catalysts for the decolourisation of dyes in the presence of H 2 O 2 ., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Simultaneous determination of sofosbuvir (SOF), and daclatasvir (DAC) in their dosage forms, human urine and human plasma using simple and rapid micellar high performance liquid chromatographic method coupled with UV detection (HPLC-UV) had been developed and validated. These drugs are described as co-administered for treatment of Hepatitis C virus (HCV). HCV is the cause of Hepatitis C and some cancers such as liver cancer (hepatocellular carcinoma) and lymphomas in humans. Separation and quantitation were carried out on anonyx™ C 8 monolithic (100 × 4.6 mm (i.d.) analytical column maintained at 25 °C. The mobile phase consisted of 0.1 M sodium dodecyl sulfate (SDS) solution containing 20% (V/V) n-propanolol and 0.3% (V/V) triethylamine and pH was adjusted to 6.5 using 0.02 M phosphoric acid, respectively. The retention times of SOF and DAC were 4.8 min, and 6.5 min, respectively. Measurements were made at flow rate of 0.5 mL/min with injection volume of 20 μL and ultraviolet (UV) detection at 226 nm. Linearity of SOF and DAC was obtained over concentration ranges of 50-400, and 40-400 ng/mL, respectively in pure form, 60-300 and 50-300 ng/mL, respectively for human plasma and over 50-400, and 40-400 ng/mL, respectively for human urine with correlation coefficient >0.999. The proposed method demonstrated excellent intra- and inter-day precision and accuracy. The suggested method was applied for determination of the drugs in pure, dosage form, and in real human plasma, real human urine and drug-dissolution test of their tablets. The obtained results have been statistically compared to reported method to give a conclusion that there is no significant differences., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Two novel stability-indicating TLC densitometric and chemometric methods were developed for the determination of mometasone furoate (MF) in the presence of its alkaline degradation product (MF Deg). The developed TLC densitometric method (Method A) is based on the quantitative densitometric separation of MF from its alkaline degradation product on silica gel 60 F254 and measurement of the bands at 250 nm. The separation was carried out using hexane-chloroform-methanol-acetonitrile (6:6:1:0.3, by volume) as a developing system. A well-resolved and compact bands for (MF) and (MF Deg) at retention factors 0.36 and 0.66, respectively. Good resolution between (MF) and (MF Deg) assured the specificity of the proposed method. The method showed good linearity in the concentration range 0.5-5 μg/band with r2 = 0.9998. The method validation was performed according to ICH guidelines demonstrating to be accurate, precise, robust and sensitive. The LOD and LOQ were found to be 0.21 and 0.63 μg/band for MF, respectively. The developed TLC-densitometric method can be applied for identification and quantitative determination of MF in bulk drug and pharmaceutical dosage forms without any interference from excipients and degradates. Method B is a multivariate chemometric-assisted spectrophotometry, where classical least squares, principal component regression and partial least squares were applied. Statistical analysis of the results has been carried out revealing high accuracy and good precision.

An easy, quick, simple and accurate spectrofluorimetric method was recognized and validated for evaluation of sorafenib (SOR) in pure form and biologically in plasma. Cremophor RH 40 (Cr RH 40) used for enhancing the fluorescence activity of SOR in phosphate buffer (pH 7). Cr RH 40 improved the native fluorescence of SOR remarkably in water. The fluorescence spectrum of SOR was observed at 405 nm after excitation at 265 nm. The linearity appeared to be in the range of 5 to 600 ng ml -1 for pure and from 9 to 500 ng ml -1 for plasma using the protein precipitation (ppt) method while from 10 to 500 ng ml -1 for plasma using liquid-liquid extraction method. The precisions and the accuracy of the estimated method gave satisfactory results. The recommended method was effectively applied for determination of SOR in human plasma with high recovery values. The results of some compounds that are possibly found in plasma were studied. The proposed method was also focused on real volunteers and a drug dissolution test., (Copyright © 2017 John Wiley & Sons, Ltd.)

The following paper represents a simple, highly sensitive, responsive validated and developed spectrofluorimetric method for estimation of imatinib (IMB) in its pure, commercial preparation, human urine and human blood plasma. The calibration curve was in the range 4-900 ng ml -1 for pure form and urine and 8-900 ng ml -1 for plasma in a medium contains carboxymethyl cellulose (CMC) and acetate buffer (pH 5) with excitation wavelength (λ ex ) 230 nm and emission wavelength (λ em ) 307 nm. The limit of detection (LOD) was 0.37 ng ml -1 for the pure form, 0.64 ng ml -1 for human urine, and 0.70 ng ml -1 for human plasma, while the limit of quantitation (LOQ) was 1.2 for pure form, 1.91 for urine and 2.1 for plasma. The suggested method was successfully applied for evaluation of IMB in tablets within 99% mean percentage recovery. The excipients that are usually used as additives in pharmaceutical dosage form did not interfere with the suggested method. The method was efficiently used for estimation of IMB in human urine and human plasma. The effect of some cations that might be present in urine and plasma was also studied. The method was also focused on human volunteers and in vitro drug release., (Copyright © 2017 John Wiley & Sons, Ltd.)

African Swine Fever Virus (ASFV) is a high-consequence transboundary animal pathogen that often causes hemorrhagic disease in swine with a case fatality rate close to 100%. Lack of treatment or vaccine for the disease makes it imperative that safe and efficacious vaccines are developed to safeguard the swine industry. In this study, we evaluated the immunogenicity of seven adenovirus-vectored novel ASFV antigens, namely A151R, B119L, B602L, EP402RΔPRR, B438L, K205R and A104R. Immunization of commercial swine with a cocktail of the recombinant adenoviruses formulated in adjuvant primed strong ASFV antigen-specific IgG responses that underwent rapid recall upon boost. Notably, most vaccinees mounted robust IgG responses against all the antigens in the cocktail. Most importantly and relevant to vaccine development, the induced antibodies recognized viral proteins from Georgia 2007/1 ASFV-infected cells by IFA and by western blot analysis. The recombinant adenovirus cocktail also induced ASFV-specific IFN-γ-secreting cells that were recalled upon boosting. Evaluation of local and systemic effects of the recombinant adenovirus cocktail post-priming and post-boosting in the immunized animals showed that the immunogen was well tolerated and no serious negative effects were observed. Taken together, these outcomes showed that the adenovirus-vectored novel ASFV antigen cocktail was capable of safely inducing strong antibody and IFN-γ+ cell responses in commercial swine. The data will be used for selection of antigens for inclusion in a multi-antigen prototype vaccine to be evaluated for protective efficacy.

New, sensitive, and selective spectrophotometric and spectrofluorometric methods have been developed for determination of clemastine hydrogen fumarate (Clem), loratadine (Lor), losartan potassium (Los), and ramipril (Ram) in both pure form and pharmaceutical formulations using 4-chloro-7-nitrobenzofurazan (NBD-CI), which is a highly sensitive chromogenic and fluorogenic reagent. The relation between absorbance at 470, 467, 471, and 469 nm and the concentration was linear over the ranges 5-35, 10-100, 10-90, and 10-120 microg/mL for Clem, Lor, Los, and Ram, respectively. The complexation products were also measured spectrofluorometrically at the emission wavelength 535 nm for Clem, Lor, and Ram and at 538 nm for Los with excitation at 477 and 452 nm for Clem and Lor, respectively, and 460 nm for both Los and Ram. The fluorescence intensity was directly proportional to the drug concentration over the ranges 0.05-0.5, 5-20, 1-6, and 2-15 microg/mL for Clem, Lor, Los, and Ram, respectively. The methods were successfully applied for the determination of the studied drugs in pharmaceutical dosage forms with excellent recovery.

A simple, selective and sensitive luminescence method has been developed for the assay of etodolac (I), moxepril HCl (II) and fexofenadine HCl (III) in bulk drug and pharmaceutical formulations. The method is based on the luminescence sensitization of europium (Eu(3+)) by complexation with the studied drugs. The fluorescence intensities of the products were measured at 667 nm for (I) and at 615 for (II) and (III) while exciting at 276 for all the studied drugs. The fluorescence intensity was directly proportional to the concentration over the range (20-280), (40-240) and (30-80) ng/ml with limits of detection (LOD) = 0.93, 0.92 and 0.95 μg/ml for drugs I, II and III respectively. Optimum conditions for the formation of the complex in methanol were carefully studied. The proposed method was successfully applied for the assay of the studied drugs in pharmaceutical formulations with excellent recovery.

Background: Etodolac (ETD) is a non-steroidal anti-inflamatory antirheumatic drug. A survey of the literature reveals that there is no method available for the determination of ETD in pure form and pharmaceutical formulations by oxidation-reduction reactions., Results: We describe three simple, sensitive and reproducible spectrophotometric assays (A-C) for the determination of etodolac in pure form and in pharmaceutical formulations. Methods A and B are based on the oxidation of etodolac by Fe3+ in the presence of o-phenanthroline (o-phen) or bipyridyl (bipy). The formation of the tris-complex on reaction with Fe3+-o-phen and/or Fe3+-bipy mixtures in acetate buffer solution at optimum pH was demonstrated at 510 and 520 nm with o-phen and bipy. Method C is based on the oxidation of etodolac by Fe3+ in acidic medium, and the subsequent interaction of iron(II) with ferricyanide to form Prussian blue, with the product exhibiting an absorption maximum at 726 nm. The concentration ranges are 0.5-8, 1.0-10 and 2-18 microg mL(-1) respectively for methods A, B and C. For more accurate analysis, Ringbom optimum concentration ranges were calculated, in addition to molar absorptivity, Sandell sensitivity, detection and quantification limits., Conclusion: Our methods were successfully applied to the determination of etodolac in bulk and pharmaceutical formulations without any interference from common excipients. The relative standard deviations were

Two rapid, simple and sensitive extractive specrophotometric methods has been developed for the determination of three histamine H1-antagonists drugs, e.g., chlorphenoxamine hydrochloride (CPX), diphenhydramine hydrochloride (DPH) and clemastine (CMT) in bulk and in their pharmaceutical formulations. The first method depend upon the reaction of molybdenum(V) thiocyanate ions (Method A) with the cited drugs to form stable ion-pair complexes which extractable with methylene chloride, the orange red color complex was determined colorimetrically at lambda(max) 470nm. The second method is based on the formation of an ion-association complex with alizarin red S as chromogenic reagents in acidic medium (Method B), which is extracted into chloroform. The complexes have a maximum absorbance at 425 and 426nm for (DPH or CMT) and CPX, respectively. Regression analysis of Beer-Lambert plots showed a good correlation in the concentration ranges of 5.0-40 and 5-70microgmL(-1) for molybdenum(V) thiocyanate (Method A) and alizarin red S (Method B), respectively. For more accurate analysis, Ringbom optimum concentration ranges were calculated. The molar absorptivity, Sandell sensitivity, detection and quantification limits were calculated. Applications of the procedure to the analysis of various pharmaceutical preparations gave reproducible and accurate results. Further, the validity of the procedure was confirmed by applying the standard addition technique and the results obtained in good agreement well with those obtained by the official method.

Corticosteroids are used to treat many diseases and are prescribed by both specialists and general practitioners. One serious side effect of steroid use is glaucoma. This complication, which can cause blindness, is often only discovered at the end stage. Three patients, two women aged 20 and 32 and a man aged 28 developed glaucoma as a result of topical steroid use. It is advisable to examine patients annually if they have a family history of glaucoma and are using steroids regularly in or around the eye. Follow-up should also be considered for patients with a family history of glaucoma who are using systemic steroids regularly, and for all other patients using steroids regularly in or around the eye. All patients on steroids should consult their ophthalmologist speedily if visual symptoms occur.

Coronary anomalies are generally rare, but has fascinating congenital cardiac disease entities, recognized in less than 1.3% of all coronary angiograms. Left coronary artery arising from right sinus of valsalva RSOV represents an extremely uncommon subtype. Initial presentations include chest pain, myocardial infarction, arrhythmias, sudden death, and rarely exertional syncope. We report a case of exertional dizziness and syncope, diagnosed to have anomalous origin of left main coronary artery from RSOV. Surgical intervention was curative.