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Abstract Purpose In this study, first, second, third, and fourth-order derivative spectrophotometric methods utilizing the peak—zero (P—O) and peak-peak (P—P) techniques of measurement were developed for the determination of levofloxacin, norfloxacin, and moxifloxacin. These methods were applied to their combined pharmaceutical dosage form or individually for levofloxacin, norfloxacin, and moxifloxacin. Methods Linearity was established in the concentration range of 2–20 µg/mL. The procedures are simple, quick, and precise. The developed methods are sensitive, accurate, and cost-effective, demonstrating excellent correlation coefficients (R2 = 0.9998) and mean recovery values ranging from 99.20% to 100.08%, indicating a high level of precision. Results The developed approach was effectively employed to determine the levofloxacin, norfloxacin, and moxifloxacin content in commercially available pharmaceutical dosages. Conclusions Statistical analysis and recovery tests confirmed the method's linearity and accuracy. The results suggest that this method can be utilized for routine analysis in both bulk and commercial formulations. The simplicity, accuracy, and cost-effectiveness of the developed methods make them valuable for pharmaceutical analysis.

Objectives: The investigation article intends is to build and validate a more convenient scientific approach to accurately simultaneously determine famotidine and para-amino benzoic acid from their cocrystals Significance: The zero-order spectra of both drugs demonstrated significant overlap between the two spectra curves; therefore, the simultaneous estimation of two drugs by zero-order spectra method was not feasible. Therefore, to overcome this and facilitate simultaneous analysis of both the therapeutic agent derivative spectrophotometry technique was employed; The sensitivity and selectivity of both the drug mixtures were enhanced by the derivative spectrophotometry technique. Materials and Methods: First-order derivative spectra were chosen for the quantitative analysis of FMT and PABA in cocrystals. Zero-crossing measurements (both calculated and plotted) were employed to select the wavelength for each drug to carry out quality control analysis. ICH guidelines were referred to validate the technique. Results: The wavelength 275 nm for FMT was selected referring to zero-crossing points (∆A/∆γ of PABA is zero at 275 nm) and 285 nm was selected for PABA (∆A/∆γ of FMT is zero at 285 nm) and no mutual intrusion was detected and these wavelengths were designated for estimation of these therapeutic agents. The linearity, accuracy, precision, and robustness of the method were validated by satisfying the statistical parameters. Conclusion: The technique established for the simultaneous assessment of drugs (FMT and PABA) from cocrystals by first-order derivative spectrophotometric technique was validated. The development of the analytical method was reliable, economical, convenient, and environmentally friendly. [ABSTRACT FROM AUTHOR]

Purpose: In this study, first, second, third, and fourth-order derivative spectrophotometric methods utilizing the peak—zero (P—O) and peak-peak (P—P) techniques of measurement were developed for the determination of levofloxacin, norfloxacin, and moxifloxacin. These methods were applied to their combined pharmaceutical dosage form or individually for levofloxacin, norfloxacin, and moxifloxacin. Methods: Linearity was established in the concentration range of 2–20 µg/mL. The procedures are simple, quick, and precise. The developed methods are sensitive, accurate, and cost-effective, demonstrating excellent correlation coefficients (R2 = 0.9998) and mean recovery values ranging from 99.20% to 100.08%, indicating a high level of precision. Results: The developed approach was effectively employed to determine the levofloxacin, norfloxacin, and moxifloxacin content in commercially available pharmaceutical dosages. Conclusions: Statistical analysis and recovery tests confirmed the method's linearity and accuracy. The results suggest that this method can be utilized for routine analysis in both bulk and commercial formulations. The simplicity, accuracy, and cost-effectiveness of the developed methods make them valuable for pharmaceutical analysis. [ABSTRACT FROM AUTHOR]

Himalaya PartySmart capsule is a polyherbal formulation having liver-protective properties. The polyherbal capsule consists of extracts of six different herbs namely, Phoenix dactylifera, Cichorium intybus, Andrographis paniculata, Vitis vinifera, Phyllanthus amarus and Emblica officinalis. A reversed-phase high-performance liquid chromatography method with ultraviolet detection was developed to standardize commercial polyherbal capsule using andrographolide and catechin as markers. Two selected markers were separated on the C18 silica gel column by isocratic elution mode using methanol, phosphate buffer (potential of hydrogen 2.5) (70:30, v/v) as mobile phase at 27° and the detection wavelength was 259 nm. The method was validated as per the recommendations of the International Conference on Harmonization Q2 (R1) guidelines. Both the calibration curves exhibited a good linear coefficient of correlation (r2>0.995). The limit of detection and limit of quantitation values indicated that the developed method was sensitive even at low concentrations. The percent relative standard deviation of peak areas was less than 2 % for intra-day and inter-day precision. The recoveries of both markers ranged between 98 %-102 %. Two markers were quantified in polyherbal capsules containing andrographolide (0.72 %, w/w) and catechin (0.94 %, w/w). In conclusion, a specific, precise, accurate and robust reversed-phase high-performance liquid chromatography method was developed to determine andrographolide and catechin simultaneously which can be used to monitor the quality control studies. [ABSTRACT FROM AUTHOR]

Bisoprolol fumarate (BSF) is a cardioselective β-blocker, whereas telmisartan (TLM) is an angiotensin II receptor antagonist. Both drugs in combination are available as a formulation product effective in the management of hypertension. As a rapid and precise analytical method, there is still no high-performance thin-layer chromatographic (HPTLC) method reported for the simultaneous estimation of both the drugs in combination. Therefore, the aim of the present study was to develop a precise, accurate, and sensitive HPTLC method for simultaneous estimation of BSF and TLM in bulk and in formulation product. The separation was achieved by using a mobile phase mixture consisting of methanol‒ethyl acetate‒glacial acetic acid (MeOH‒EA‒GAA; 6:4:0.1, V/V). The retention factor (RF) for BSF and TLM was found to be 0.435 ± 0.04 and 0.699 ± 0.04, respectively, and the peak areas were determined at 231 nm. The method was subsequently validated as per the International Council for Harmonisation of Technical Requirements for Pharmaceuticals for Human Use (ICH) Q2 (R1) guidelines. A linear relationship was obtained between the concentration ranges and peak areas with correlation coefficient (R2) ≥ 0.999. The developed method was found to be accurate, precise, and robust. The method was then applied for analysis of three different batches of marketed product, and the percent content for BSF and TLM in the formulation was found to be > 98.0% w/w. [ABSTRACT FROM AUTHOR]

Quercetin and beta-sitosterol (β-sitosterol) are prominent phytoconstituents that are being widely used in food ingredients and medicinal applications due to their various pharmacological activities and therapeutic activities including anti-inflammatory, anti-cancer, and anti-diabetic properties. The main aim of this paper is the development and validation of a robust reverse phase high-performance liquid chromatography (RP-HPLC) method for the simultaneous estimation of quercetin and β-sitosterol. Gradient elution was performed using a mixture of water, acetonitrile and acetic acid, with varying ratios of water:acetonitrile:acetic acid (50:50:2). The flow rate was set at 0.9 mL/min, and the detection wavelength was fixed at 370 nm. The developed method was validated according to the International Conference of Harmonization (ICH) Q2 (R1) guidelines. The method was linear in the concentration range of 1–5 µg/mL quercetin and β-sitosterol. The limit of detection (LOD) and limit of quantification (LOQ) were 0.118 and 0.358 µg/mL for β-sitosterol, respectively, while LOD and LOQ for quercetin were 0.127 µg/mL and 0.387 µg/mL respectively. The percentage recovery ranged from 95 to 105% with a relative standard deviation of less than 2%, indicating the accuracy and precision of the method for both compounds. Furthermore, the validated method was found specific to detect presence of both the drugs in Nyctanthes arbortristis leaf extract. The developed method is the first of its type method that is capable of simultaneous estimation of β-sitosterol and quercetin from Nyctanthes arbortristis leaves and demonstrated with excellent specificity, linearity, accuracy and precision. Consequently, it holds great potential for the detection of β-sitosterol and quercetin in food, biological samples and various marketed formulations. [ABSTRACT FROM AUTHOR]

Apigenin and gallic acid are advantageous for people's health since they aid in the treatment of liver illness. The study mainly illustrated that a simple, rapid, accurate, economic, and precise UV–visible spectrophotometry method has been developed and validated. Methods are validated according to the ICH guidelines and can be adopted for the routine analysis of gallic acid and apigenin in hepatoprotective polyherbal formulation. Choices of a common solvent were essential so various solvent ranges including methanol, ethanol, and acetonitrile were analyzed. Hence, methanol was selected as a solvent for the proposed method. Gallic acid and apigenin showed maximum absorbance at 217 and 268 nm, respectively. Both drugs obey Beer–Lambert's law in the concentration range of 0.5 µg mL−1–3 µg mL−1 for gallic acid and apigenin, respectively. The limit of detection and limit of quantification were found to be 0.00379 µg mL−1 and 0.011 µg mL−1 for gallic acid, respectively. For apigenin, the limit of detection and limit of quantification values were found to be 0.00801 µg mL−1 and 0.024 µg mL−1, respectively. The method was validated statistically and by recovery studies for linearity, precision, repeatability, and reproducibility. The obtained results proved that the method can be employed for the routine analysis of gallic acid and apigenin in bulks as well as in the commercial herbal formulations. [ABSTRACT FROM AUTHOR]

Clinical research has affirmed that the combination of Udenafil and Dapoxetine hydrochloride yields greater improvement in erectile dysfunction compared to the use of individual medications. There is a requirement of precise quantitative method for accurate determination of Udenafil and Dapoxetine when taken together. Consequently, our interest lies in developing and validating analytical methods for the simultaneous estimation of Udenafil and Dapoxetine - Various strategies, such as UV spectrophotometric approaches and an innovative, straightforward, accurate, sensitive, and robust High-Performance Liquid Chromatography (HPLC) procedure, have been explored. An Isocratic HPLC approach was employed using reversed-phase CHEMSIL ODS C18 column (4.6 mm x 250 mm, 5 µm) as a stationary phase and detection wavelength (λ max) 230 nm for the two analytes in the chromatographic column. The mobile phase comprised of (70:30, v/v) mixture of Acetonitrile and 10 mM Ammonium formate buffer having pH 5, adjusted with formic acid. The elution was carried out at a constant flow rate of 1 mL/min. The UV simultaneous equation technique estimated the medicine's quantities and derived a simultaneous equation for DAP and UDN using 2 wavelengths, 230 nm and 298 nm. Furthermore, the two advanced methods underwent rigorous statistical validation, guided by the valuable ICH Q2R1 guidelines, affirming their effectiveness as a successful analytical tool for the concurrent analysis of both tablets in bulk and the synthetic mixture fabricated in the laboratory. To assess the environmental impact of contemporary UV spectrophotometric and HPLC techniques, the Green Analytical Greenness Metric (AGREE) software and the Green Analytical System Index (GAPI) were employed to evaluate the greenness profile. This examination confirmed the method's environmental friendliness concerning solvent usage, chemical ingredients, energy consumption, and waste production. The developed UV method is more sustainable and greener compare to HPLC method for simultaneous estimation of compound, which can be utilised by industry for quantification of each individual drug in their combination products.

Motivated by three health economics-related case studies, we propose a unifying and flexible regression modeling framework that involves regimeswitching. The proposal can handle the peculiar distributional shapes of the considered outcomes via a vast range of marginal distributions, allows for a wide variety of copula dependence structures and permits to specify all model parameters (including the dependence parameters) as flexible functions of covariate effects. The algorithm is based on a computationally efficient and stable penalized maximum likelihood estimation approach. The proposed modeling framework is employed in three applications in health economics, that use data fromtheMedical Expenditure Panel Survey, where novel patterns are uncovered. The framework has been incorporated in the R package GJRM, hence allowing users to fit the desiredmodel(s) and produce easy-to-interpret numerical and visual summaries. [ABSTRACT FROM AUTHOR]

For the simultaneous estimation of Benidipine hydrochloride (BEN) and Telmisartan (TEL) in combined pharmaceutical dosage form, a stability‐indicating high‐performance thin‐layer chromatography (HPTLC) method has been developed and validated. It involves the use of HPTLC plates pre‐coated with silica gel 60F254 and a mobile phase comprising of Methanol: Acetonitrile (1:9 v/v). The measurements of both drugs were performed at 237 nm. The drugs were subjected to acid‐alkali hydrolysis, photolytic, thermal, and oxidation degradation. The linearity of BEN was found to be between 200–1000 ng/band (R2 = 0.9917), while for TEL, linearity was found to be between 2000 and 10000 ng/band (R2 = 0.9979). The limit of detection and limit of quantitation were found to be 3.28 and 9.94 ng/spot for BEN and 158.79 and 481.17 ng/spot for TEL. The % relative standard deviation of the precision study was determined to be less than 2%. Various system suitability parameters were determined. The Rf values of BEN and TEL were found to be 0.890 ± 0.0105 and 0.173 ± 0.0151, respectively. The resolution between BEN and TEL peak were found to be 4.48 and capacity factors were found to be 0.21 and 0.74 for BEN and TEL, respectively. [ABSTRACT FROM AUTHOR]

Elemental impurities are the traces of metals that can be found in finished drug products which may enter through various sources like excipients, and active pharmaceutical ingredients etc., their toxicity is to be estimated as they may pose serious toxicological effects to patients. The aim of this work is to estimate Class-I elements (Cd, Pb, As, Hg) simultaneously in Propofol 10 mg/mL Emulsion for Injection or Infusion using modern technique Inductively coupled plasma mass spectrometry, employing microwave-assisted digestion of sample. The developed method was validated for various parameters according to ICHQ2(R1) to prove that the developed method is fit for the required purpose and can be adaptable regularly. Validation results showed that the method was linear over the range of LOQ to 250%, with a good linearity correlation factor of R=0.99, the method was found to be robust against the deliberate changes in sample preparation and uptake speed. [ABSTRACT FROM AUTHOR]

Using China's 2008 enterprise income tax (EIT) reform, this study examines the effect of EIT on corporate innovation comprehensively. Based on accurate identification of the direction of changes in the corporate tax rate, we introduce two dummy variables of tax rate decline and escalation to investigate the impact of EIT changes simultaneously. Using the firm-level dataset from China's A-share listed companies, we find that the innovation level of tax-rate-declining enterprises will increase by 0.2%, whereas the innovation level of tax-rate-increasing enterprises will decrease by 0.4%. The dynamic effect demonstrates that the aforementioned promoting and inhibitory effects are continuous. Heterogeneity analyses reveal that the changes in the EIT rates have a greater impact on the innovation level of enterprises with high innovation demand, manufacturing enterprises, enterprises in a high rule of law environment, and enterprises in the eastern region. Our study highlights the importance of the EIT reform on corporate innovation and guides how to better optimize the effectiveness of such policies. [ABSTRACT FROM AUTHOR]

The roots of Potentilla fulgengs have been utilized for a long time as an astringent and tonic for treating gum and tooth diseases, microbial contagions, inflammation, diabetes mellitus, and wounds and are rich in polyphenols and flavonoids. Authentication and constant excellence are the rudimentary limitations of herbal medicines and their complexity is a key challenge for quality control. High‐performance liquid chromatography has become an important technique for the quality control of herbal medicines because of its simplicity and uniformity. It can be applied for the identification, confirmation, and quality control of herbal medicines. So, an approach using reversed‐phase high‐performance liquid chromatography was developed and validated for the simultaneous determination of phenolic compounds in the hydroalcoholic extract (methanol:water::70:30% v/v) of Potentilla fulgens roots. The results revealed that ellagic acid was found in the highest amount (8.191 ± 0.463 mg/g) followed by rutin (5.429 ± 0.062 mg/g) and caffeic acid (3.032 ± 0.453 mg/g) among the studied phenolic compounds while quercetin was not detected. The validation parameters involved selectivity, linearity, range, limits of detection and quantitation, precision, and accuracy. All calibration curves were linear (R2 > 0.99) within the range, and good precision (relative standard deviation < 2.0%) and recovery (96.129%–117.110%) were found for all standards. [ABSTRACT FROM AUTHOR]

The present study delineates the development of a novel rugged and sensitive stability‐indicating risk‐based HPLC method for the concurrent estimation of methotrexate and mangiferin in dual drug‐loaded nanopharmaceuticals based on an analytical QbD approach. Preliminary screening trials along with systemic risk analysis were performed, endeavouring to explicate the critical method attributes, namely pH, percentage orthophosphoric acid content and percentage methanol content, that influence critical quality attributes. Box–Behnken design was utilized for the optimization of the tailing factor as response for methotrexate and mangiferin in short run time. The chromatographic conditions were optimized by performing 17 experimental runs acquired from Design‐Expert software. The chromatographic conditions after the analysis of an optimized zone within the confines of the design space were chosen as mobile phase water–methanol adjusted to pH 3.0 with 0.05% orthophosphoric acid (65:35, v/v) and flow rate 1.0 ml/min using a C18 analytical column at an isosbestic wavelength of 265 nm. Furthermore, the validation of the optimized method was done in accordance with International Conference on Harmonization guidelines and were reckoned to be in the prescribed limits. The developed RP‐HPLC method has a high degree of practical utility for synchronous detection of methotrexate and mangiferin in pharmaceutical nano‐dosage forms such as protein‐based‐nanoparticles, nanocrystals, polymeric nanoparticles and metallic nanoparticles in in vivo and in vitro studies. [ABSTRACT FROM AUTHOR]

The development and analysis of pharmaceutical formulations often involves the determination of multiple active ingredients in a dosage form. The aim of the present study is to develop a convenient method for simultaneous estimation of Exemestane (EXE) and Everolimus (EVE) in bulk and in systemically designed tablet dosage form. Methanol was used as a solvent for developing linear curves and validated in terms of various parameters, such as selectivity, sensitivity, linearity, precision, accuracy, and robustness. Method validation observed that the proposed method is reliable and reproducible, meeting the regulatory requirements for pharmaceutical analysis with a relative standard deviation of <2%. The developed method was found to be sensitive and selective in simultaneous equation method. The unknown concentrations of EVE and EXE were found to be 10.431 and 10.232, respectively. The next step is to systematically design a tablet formulation for EXE and EVE containing β-cyclodextrin as a polymer. Microcrystalline cellulose (X1), sodium starch glycolate (X2), and beta-cyclodextrin (X3) are the critical variables and hardness (Y2) and friability (Y3) were selected as prime responses. Analysis of variance provides significance of the model, and the predicted batch gives a high desirability value of 0.862. In vitro dissolution profiles of optimized batch (OB1) were signified by high drug release profile as 89.47% and 96.00% for EVE and EXE in tablet formulation, as compared with pure API, respectively. This study signifies enhancement in biopharmaceutical attributes of EXE and EVE in tablet formulation and robust simultaneous estimation by the UV method. In a nutshell, this study provides the simultaneous estimation method in tablet dosage form, and further research is crucial for the advancement of pharmaceutical analysis and the formulation of effective medicines. [ABSTRACT FROM AUTHOR]

Combinatorial treatment utilizing a nucleoside analogue gemcitabine (GEM), with a characteristic pentacyclic triterpenoid betulinic acid (BET), has exhibited empowering adequacy in the therapy of cancer. It lessens the advancement of collagen and upgrades the saturation of tumour medicines. With the advancement in nanotechnology, the co-loaded formulation urges for a validated method of estimation. The purposed work entails a robust, simple, and economical analytical method for the simultaneous estimation of GEM and BET through RP-HPLC. Orthophosphoric acid (0.1%)—acetonitrile was considered as the mobile phase for the detection of GEM and BET at 248 nm and 210 nm with retention times of 5 min and 13 min, respectively. The method was further validated as per the regulatory guidelines with all the parameters found within the limit. The developed method with adequate resolution and quantification was found to be linear, accurate, precise, robust, and stable with an intra- and inter-day variability of less than 2%. The method was found specific for GEM and BET with no matrix interference of drug-spiked FBS samples. To demonstrate the applicability of the developed method, a nano-formulation containing GEM and BET was prepared and assessed for various parameters including encapsulation efficiency, loading efficiency, drug release, and drug stability. The method developed can be a possible tool for the simultaneous quantification of GEM–BET in analytical and biological samples. [ABSTRACT FROM AUTHOR]

Objectives: Fluconazole (FCZ) and Quercetin (QCT) in pharmaceutical dosage form were simultaneously quantified using a sensitive, accurate, robust, and précised Reverse Phase-HPLC Method. Materials and Methods: RP-HPLC method was used to get the separation of FCZ and QCT using Imtakt® Unison-US-C18 column having a size of the particle, 5 µm (150 mm x 4.6 mm) operating at a 1.3 mL/min flow rate with an optimized mobile phase having Methanol-Water-Trifluoroacetic acid (TFA) in the proportion of 50:50:1%, v/v/v, respectively. The quantification of FCZ and QCT was done at 258 nm wavelength. Results and Discussions: In the developed method FCZ was retained at a retention time of 1.896 min, while QCT was retained at a retention time of 5.637 min. The proposed method separates FCZ and QCT with a resolution of 13.261. The validation of the method was done with reference to the guideline of ICH Q2(R1). FCZ and QCT showed linearity at 4-20 µg/mL, and 1-5 µg/mL, respectively. The % RSD for the precision study was less than 2 and recovery was in the range of 98.69% to 102.14% for both drugs. In the robustness study, the proposed method has less than 2 % RSD. Conclusion: The Method can be used to quantify Fluconazole and Quercetin simultaneously in a newly developed thermosensitive in-situ mucoadhesive vaginal gel formulation. [ABSTRACT FROM AUTHOR]

The current work delineates the development of a novel, rugged and sensitive stability‐indicating risk‐based HPLC method based on an analytical quality‐by‐design (QbD) approach for the concurrent estimation of naringin and pregabalin in dual‐drug‐loaded nanopharmaceuticals. Preliminary screening trials were conducted, along with systemic risk analysis, in order to identify the critical method attributes, namely injection volume, pH and acetonitrile content, that influence critical quality attributes. The Box–Behnken design was used to optimize the tailing factor as a response to pregabalin and naringin in a short run time. The chromatographic conditions were improved by running 17 experimental runs generated by design expert software. After analysing the optimized zone within the confines of the design space, the following chromatographic conditions were chosen: mobile phase water–acetonitrile adjusted to pH 6.9 with phosphate buffer (80:20, %v/v), at flow rate of 1.0 ml/min using a C18 analytical column at an isobestic wavelength of 212 nm. Furthermore, the optimized method was validated in accordance with International Conference on Harmonization guidelines and was found to be within the prescribed limits. The developed RP‐HPLC method has a high degree of practical utility in in vivo and in vitro studies for the synchronous detection of pregabalin and naringin in pharmaceutical nanodosage forms such as protein‐based nanoparticles, nanocrystals, polymeric nanoparticles and metallic nanoparticles. [ABSTRACT FROM AUTHOR]

We develop a flexible two‐equation copula model to address endogeneity of medical expenditures in a distribution regression for health. The expenditure margin uses the compound gamma distribution, a special case of the Tweedie family of distributions, to account for a spike at zero and a highly skewed continuous part. An efficient estimation algorithm offers flexible choices of copulae and link functions, including logit, probit and cloglog for the health margin. Our empirical application revisits data from the Rand Health Insurance Experiment. In the joint model, using random insurance plan assignment as instrument for spending, a $1000 increase is estimated to reduce the probability of a low post‐program mental health index by 1.9 percentage points. The effect is not statistically significant. Ignoring endogeneity leads to a spurious positive effect estimate. [ABSTRACT FROM AUTHOR]

In the present investigation, methanol is employed as the solubilizing agent to solubilize poorly watersoluble drugs such as praziquantel and abamectin. UV spectrophotometric method has been developed for simultaneous estimation of praziquantel and abamectin in bulk drug and in their combined pharmaceutical dosage form by first order derivative method. This method utilizes methanol as a common solvent and λmax of praziquantel and abamectin selected for analysis was found to be at 248 nm (at ZCP of abamectin) and 274 nm (at ZCP of praziquantel), respectively. Linearity was observed in the concentration range of 25-150 µg mL-1 for praziquantel (r² = 0.9984) and 1-11 µg mL-1 for ABAM (r² = 0.9986). The accuracy and precision were determined and found to comply with ICH guidelines. This method shows good reproducibility and recovery with % RSD in the desired range. Developed method was applied for marketed formulation. The results were found to be within acceptance criteria according to ICH guideline. [ABSTRACT FROM AUTHOR]

The present study delineates the development of a novel, rugged and sensitive stability‐indicating risk‐based HPLC method for the concurrent estimation of methotrexate (MTX) and baicalin (BCL) in dual‐drug‐loaded‐nanopharmaceuticals based on an analytical quality‐by‐design approach. Preliminary screening trials along with systemic risk analysis were performed, endeavouring to explicate the critical method attributes, namely pH, percentage of orthophosphoric acid and percentage of acetonitrile, that influence the critical quality attributes. Box–Behnken design was utilized for the optimization of the tailing factor as the response for MTX and BCL in a short run time. The chromatographic conditions were optimized by performing 17 experimental runs using design expert software. The chromatographic conditions were selected after the analysis of the optimized zone within the confines of the design space: water:acetonitrile adjusted to a pH of 3.0 with 0.05% orthophosphoric acid (60:40, %v/v) was the mobile phase, the flow rate was 1.0 ml/min and an analytical C18 column was used at an isobestic wavelength of 282 nm. Furthermore, the optimized method was validated in accordance with the International Council for Harmonisation of Technical Requirements for Registration of Pharmaceuticals for Human Use guidelines and was found to be within the prescribed limits. Therefore, the developed reversed‐phase‐high‐performance liquid chromatography method has a high degree of practical utility for synchronous detection of MTX and BCL in pharmaceutical nano‐dosage forms such as protein‐based nanoparticles, nanocrystals, polymeric nanoparticles and metallic nanoparticles in in vivo and in vitro studies. [ABSTRACT FROM AUTHOR]

For the simultaneous estimation of Bisoprolol Fumarate and Hydrochlorothiazide in combined pharmaceutical dosage form, a simple, selective, rapid, and precise stability indicating high‐performance thin‐layer chromatography method has been developed and validated. The proposed high‐performance thin‐layer chromatography technique includes the usage of high‐performance thin‐layer chromatography plates (Merck) pre‐coated with silica gel 60F254 on aluminum sheets and a cellular segment comprising of methanol:acetonitrile (8:2, v/v). The densiometric measurement of both drugs was performed in the absorbance mode at 223 nm. The method has been used to accurately estimate Bisoprolol Fumarate and Hydrochlorothiazide in a combined tablet dosage form. Both the drugs had been subjected to acid‐alkali hydrolysis, photolytic, thermal, and oxidation degradation and each of them had been discovered to be prone to acid‐alkali hydrolysis, photolytic, thermal, and oxidation degradation. The developed stability‐indicating analytical method was validated. The various validation parameters checked are linearity, inter‐day and intra‐day precision, robustness, accuracy, and so forth. The degradation products obtained were well resolved from the pure drugs with significantly different Rf values. The method can be utilized for stability‐indicating analysis since it successfully separates the drug from its degradation products. The method was successfully validated and validation results are within the acceptable range of International Council for Harmonization guidelines. [ABSTRACT FROM AUTHOR]

Introduction: Diffusion-weighted imaging (DWI) with parallel reconstruction may suffer from a mismatch between the coil calibration scan and imaging scan due to motions, especially for abdominal imaging. Methods: This study aimed to construct an iterative multichannel generative adversarial network (iMCGAN)-based framework for simultaneous sensitivity map estimation and calibration-free image reconstruction. The study included 106 healthy volunteers and 10 patients with tumors. Results: The performance of iMCGAN was evaluated in healthy participants and patients and compared with the SAKE, ALOHA-net, and DeepcomplexMRI reconstructions. The peak signal-to-noise ratio (PSNR), structural similarity index measure (SSIM), root mean squared error (RMSE), and histograms of apparent diffusion coefficient (ADC) maps were calculated for assessing image qualities. The proposed iMCGAN outperformed the other methods in terms of the PSNR (iMCGAN: 41.82 ± 2.14; SAKE: 17.38 ± 1.78; ALOHA-net: 20.43 ± 2.11 and DeepcomplexMRI: 39.78 ± 2.78) for b = 800 DWI with an acceleration factor of 4. Besides, the ghosting artifacts in the SENSE due to the mismatch between the DW image and the sensitivity maps were avoided using the iMCGAN model. Discussion: The current model iteratively refined the sensitivity maps and the reconstructed images without additional acquisitions. Thus, the quality of the reconstructed image was improved, and the aliasing artifact was alleviated when motions occurred during the imaging procedure. [ABSTRACT FROM AUTHOR]

Abstract Epilepsy is a disorder of the central nervous system, in which the nerve cell activity in the brain is disturbed causing seizures. The objective was to develop an RP-HPLC method for consistent simultaneous quantitation of four antiepileptic drugs Levetiracetam (LVT), Lamotrigine (LTG), Phenobarbital (PBT) and Phenytoin (PTY). An isocratic method was developed on C18 column in JASCO HPLC using 5 mM potassium phosphate buffer (pH 6) and acetonitrile as the mobile phase at a flow rate of 1ml/min and detected at 230 nm using UV detector. The mean retention time for LVT, LTG, PBT and PTY were found as 2.55, 3.55, 4.65 and 5.99 minutes respectively. The method was validated as per ICH guidelines and was found to be acceptable. The %RSD value was

Objectives: This study aimed to develop a micellar liquid chromatography-based simultaneous estimation method for the analysis of topotecan and capsaicin. Materials and Methods: The Liquid chromatographic system consisted of the Shimadzu Prominence HPLC model (Shimadzu Corp., Kyoto, Japan) containing an LC-20AT isocratic pump, an autosampler SIL-20AC, and a diode array detector SPD-M20 A (190-800 nm) was used. The drugs were analyzed at a wavelength of 230 nm using sodium dodecyl sulfate, buffer salt (0.01 M sodium dihydrogen phosphate), and n-butanol (7%) as mobile phase. Results: The developed Micellar liquid chromatography-Photodiode Array Detection (MLC-PDA) method successfully eluted the topotecan and capsaicin with retention times of 6.2 min and 16.3, respectively. The developed method has displayed the limits of detection i.e. 0.05 and 0.98 µg/mL and limits of quantification i.e 0.08 and 1.25 µg/mL for topotecan and capsaicin, respectively. Statistical analysis further demonstrated that the developed method is linear, exact, accurate, and specific for the analysis of topotecan and capsaicin. The method was verified as per the ICH guidelines. Conclusion: The developed MLC-PDA method was found to be precise, simple, and reproducible. The developed MLC-PDA method successfully estimated the topotecan and capsaicin from the combination of drugs. Micellar chromatography is an accurate, rapid, cost-effective, and less hazardous method as compared to HPLC. [ABSTRACT FROM AUTHOR]

Logical strategy is the heart of drug investigation. The current work endeavored to foster precise, straightforward, and delicate techniques for concurrent assessment of rabeprazole and levosulpiride. The overlay range of levosulpiride and rabeprazole display λmax of 288 nm and 282 nm for LEVO and RABE. Standard adjustment bends for levosulpiride and rabeprazole were straight with connection coefficient (r) values in the scope of 0.9998-0.9997 at all chosen frequencies. The precision of the technique was affirmed by recuperation contemplated from the tablet at three distinct degrees of 80%, 100 percent, and 120% recuperation in the scope of 99.97-100 percent legitimizes the exactness of the strategy. Intraday and Interday accuracy was checked for UV strategy, and % RSD was viewed as under 2 for UV technique. The created strategy is a fast device for routine examination of rabeprazole and levosulpiride in the mass and the drug dose structure. Considering the possible general improvement of phony medication portions, the proposed strategy could be important for the quality control research offices in developing countries. [ABSTRACT FROM AUTHOR]

A reverse phase chromatography technique to simultaneously estimate ciprofloxacin HCl and olopatadine HCl as bulk drugs and in formulation has been developed. The chromatographic separation of drugs and formulation was accomplished on C18 Agilent Zorbax column (250 x 4.6 mm, 5 µm) using acetonitrile: TFA water (40:60, V/V). A 10 µL volume was injected with flow rate 1 mL min-1, and peaks were detected. The retention periods for ciprofloxacin HCl and olopatadine HCl were 2.92 and 5.10 minutes respectively. The method was linear in the concentration ranges 24-36 µg mL-1 and 56- 84 µg mL-1 for ciprofloxacin HCl and olopatadine HCl, with regression coefficient correlation values of 0.9999 and 0.9996, respectively. Relative standard deviation of precision, accuracy, and ruggedness was below 2 %. Forced degradation studies were performed under different conditions which were in an admissible range. The established method was simple, accurate, and precise. Therefore, it can be applied for the routine quantification and degradation of these drugs and formulation. [ABSTRACT FROM AUTHOR]

In this ever-growing world, it is crucial to improve upon the formulations in terms of potency, patient acceptability, fewer side effects, and quicker relief. Due to these requirements, the market is flooded with various combination dosage forms, with a constant increase in number. Paracetamol is a commonly used non-steroidal anti-inflammatory drug (NSAID) that has antipyretic and analgesic action. This drug is available in a wide range of combinations. It acts by inhibiting the production of prostaglandins, which combat pain and inflammation. A simultaneous multicomponent analysis is used to determine the estimation of medicines that are available in combination. Different analytical techniques are available for their determination, one of which includes the use of UV spectrophotometric methods. This review focuses on a variety of paracetamol combinations with drugs like Domperidone, Aceclofenac, Diclofenac Sodium, Etodolac, Ibuprofen, Piroxicam, Caffeine, Aspirin, and their simultaneous estimation by different UV methods viz. Simultaneous equation method, Absorbance ratio (QAnalysis), Difference spectrophotometry, Derivative spectroscopy method, and a few other chemometric methods. This manuscript would provide the platform to have exhaustive literature on methods used for the estimation of paracetamol with different drugs using a spectrophotometer. It would help the researchers and scholars who are working in the area. [ABSTRACT FROM AUTHOR]

The current research work describes the development of a rapid HPLC method for the concurrent detection of pregabalin and piperine in dual drug‐loaded nanoformulations. The primary goal was to recognize the chromatographic conditions wherein propitious segregation of the integrants with quality peaks can be attained. An attempt to expound the target analytical profile was made to accomplish this goal, and critical method attributes (CMAs), viz. percentage acetonitrile content, injection volume and pH, which affect critical quality attributes (CQAs), were identified using systemic risk analysis. Box–Behnken design was employed to develop a relationship between CMAs and CQAs, which engenders an analytical design space. Efficient chromatographic separation for pregabalin and piperine was attained using an analytical C18 column and mobile phase comprising acetonitrile–water (pH 6.9; 70:30%, v/v) in an isocratic elution mode with a 1 ml/min flow rate. The elution was descried at an isosbestic wavelength of 221 nm using a photodiode array detector. The International Conference on Harmonization guidelines were adopted for the developed HPLC method. The validated HPLC method can be further utilized for the simultaneous quantification and detection of pregabalin and piperine in other lipid‐based nanopharmaceuticals such as polymeric nanoparticles, nanocrystals, solid‐lipid nanoparticles, metallic nanoparticles, etc., in in vitro and in vivo studies. [ABSTRACT FROM AUTHOR]

In this article, we consider the filtering problem of an optical parametric oscillator (OPO). The OPO pump power may fluctuate due to environmental disturbances, resulting in uncertainty in the system modeling. Thus, both the state and the unknown parameter may need to be estimated simultaneously. We formulate this problem using a state-space representation of the OPO dynamics. Under the assumption of Gaussianity and proper constraints, the dual Kalman filter method and the joint extended Kalman filter method are employed to simultaneously estimate the system state and the pump power. Numerical examples demonstrate the effectiveness of the proposed algorithms.

A simple, sensitive, and accurate chromatography (RP-HPLC) method for simultaneous estimation of Ciprofloxacin, Ofloxacin, and Marbofloxacin in their combined pharmaceutical dosage form or individually. The HPLC separation was achieved on a Hypersil (C18, 150 mm × 4.6 mm, 5 μm particle size) analytical column or equivalent. A mixture of triethanolamine (1 %), acetonitrile (80 %), and water was used as the mobile phase, with a flow rate of 1.2 mL /min and a detector wavelength of 280 nm at ambient temperature. In the HPLC method, the retention times of Ciprofloxacin, Ofloxacin, and Marbofloxacin were found to be 1.854, 2.480, and 4.688 min, respectively, and linearity was obtained in the range of 25–80 µg/mL for Ciprofloxacin, Ofloxacin, and Marbofloxacin. The correlation coefficient for the method was greater than 0.999. The RP-HPLC method validation parameter lay within its acceptance criteria as per the ICHq2 (R1) guideline. Hence, it can be successfully used for routine analysis of Ciprofloxacin, Ofloxacin, and Marbofloxacin in raw material or pharmaceutical dosage forms.

Setebid tablet is the natural antihyperglycemic agent with powerful antioxidant action. A highperformance thin layer chromatography method was developed for simultaneous estimation of mangiferin and berberine from setebid tablets. Camag Linomat 5 sample applicator was used for application of sample. Chromatographic separation of drugs was performed over thin layered chromatography plates pre-coated with silica gel 60F254 using toluene:acetone:formic acid (3.5:5.5:1 v/v/v) as the mobile phase via a linear ascending technique in twin trough chamber. Detection and quantification were carried out at an iso-absorptive wavelength of 261 nm using thin layered chromatography scanner III. This method showed good resolution for both drugs with retention factor 0.39±0.03 and 0.80±0.03 for mangiferin and berberine, respectively. The calibration curves were linear in the range of 400-800 and 100-500 ng/spot for mangiferin and berberine and correlation coefficients (r2) were 0.9995 and 0.9991, respectively. The method was validated according to the international conference on harmonisation Q2 R1 guidelines for accuracy, precision, limit of detection, linearity, limit of quantification, robustness and specificity. The limits of detection were 26.18 and 18.50 ng/spot for mangiferin and berberine, respectively. In conclusion, the developed method was rapid, simple, reliable and specific for the identification and quantification of mangiferin and berberine. [ABSTRACT FROM AUTHOR]

A method was established for simultaneous valuation of Nebivolol hydrochloride (NBH) and Hydrochlorothiazide (HYT) from the tablet dosage form by partial simultaneous equation method, the method was found to be sensitive and accurate. The maxima of both the drugs were noted in 0.1 N hydrochloric acid. The NBH has lambda maxima at 283 nm and HYT at 270 and 320 nm. As NBH shows no absorbances at 320nm. So effective wavelengths designated were 283 nm and 270 nm for Method I, 283 nm, and 320 nm for Method II. The results of analysis for the method I exhibited greater values of standard deviation (SD), standard error of the mean (SEM), coefficient of variation (COV) and percentage range of error (within 95% confidence limit) (PROE), and thus showed less precision of the method. The results of method II analysis of marketed formulations expressively indicated fewer values. To test the accuracy and reproducibility, recovery experiments were performed. The fewer SD values depicted the novelty of the method. The method can be said to be reproducible, accurate, and precise. Thus, it was established that the method-II developed was an accurate one and can efficiently be simple, accurate, sensitive, and precise. Hence, the above two equations can be efficiently applied for the simultaneous determination of NBH and HYT in marketed formulations. [ABSTRACT FROM AUTHOR]

Oxitard capsules, a polyherbal formulation, is an effective natural antioxidant that prevents oxidative stress-related tissue damage and is helpful for coronary artery disease. The aim of the present work was systematic development and validation of the high-performance thin-layer chromatographic method for simultaneous quantitative estimation of mangiferin and gallic acid from oxitard capsules. Both markers, mangiferin and gallic acid were separated on a pre-coated silica gel 60 F254 thin-layer chromatographic plate, using toluene:ethyl acetate:formic acid:methanol (4:6:0.8:2 v/v/v/v) as mobile phase. The retention factor of mangiferin and gallic acid was found to be 0.28±0.03 and 0.78±0.03, respectively. The linear regression analysis data for the calibration plots of drugs scanned at isosbestic point 299 nm showed a good linear relationship with r²=0.9931 and r²=0.9901, over the concentration range of 300 to 700 ng/spot and 500 to 900 ng/spot for mangiferin and gallic acid, respectively. The validation parameter followed for simultaneous estimation of these polyherbal drugs were linearity, precision, accuracy, robustness, ruggedness and sensitivity (limit of detection and limit of quantitation). The method was found to be precise, accurate, sensitive and robust meeting all the parameters as per International Council for Harmonisation guideline Q2 (R1). Thus, the developed high-performance thin-layer chromatography method can conveniently be employed for simultaneous detection and quantification of mangiferin and gallic acid in commercial polyherbal formulation. [ABSTRACT FROM AUTHOR]

Selective catalytic reduction (SCR) controller achieves high NO x conversion and low NH 3 slip primarily by means of controlling the rate and timing of injection of urea solution. No any low-cost commercial sensor can directly measure the actual ammonia (NH 3) injection rate currently; thus, it is necessary to propose a numerical method to estimate the actual NH 3 injection rate, which helps stabilization of emission control performances of a diesel SCR system during its service life cycle. A three-state nonlinear model was established and a method for designing high-gain observer (HGO) was studied so that those state variables such as NH 3 injection rate, NO x concentrations, NH 3 concentrations and NH 3 coverage ratio can be estimated simultaneously. Such design method only requires bounded unknown input dynamics rather than any assumption of the fact how the unknown input changes. The simulation verification was performed by the ETC test cycles and qualitative and quantitative analysis of estimation errors were carried out. Compared with the extended Kalman filter (EKF) observer, the proposed high-gain observer has a higher estimation accuracy and better target traceability. • A three-state nonlinear model was established to describe the dynamics of SCR system. • NH 3 injection rate and states of a SCR system were estimated by HGO simultaneously. • The design method only requires the limited input ammonia concentration dynamics. • Both qualitative and quantitative analysis of estimation errors were carried out. • The HGO has higher estimation accuracy and better traceability compared with the EKF. [ABSTRACT FROM AUTHOR]

The greenness indices of literature analytical procedures for the simultaneous measurement of rhein and aloe-emodin have not been determined. As a consequence, the first goal of this study was to design and validate a sensitive and sustainable reverse-phase high-performance thin-layer chromatography (HPTLC) method for the simultaneous estimation of rhein and aloe-emodin in a traditional extract (TE) and ultrasound-based extract (UBE) of commercial Rhubarb and Rhubarb plant extracts in comparison to the conventional normal-phase HPTLC method. The second goal was to determine the greenness indices for both methods using the AGREE approach. For the sustainable reverse-phase HPTLC approach, the method was linear in the 50–1000 ng/spot range for rhein and 25–1000 ng/spot range for aloe-emodin. However, for the conventional normal-phase HPTLC approach, the method was linear in the 50–600 ng/spot range for rhein and 100–600 ng/spot range for aloe-emodin. The limit of detection (LOD) for rhein and aloe-emodin was 16.81 ng/spot and 8.49 ng/spot, respectively, using the sustainable analytical method. However, the LOD for rhein and aloe-emodin was 18.53 ng/spot and 39.42 ng/spot, respectively, using the conventional analytical method. For the simultaneous determination of rhein and aloe-emodin, the sustainable analytical method was more sensitive, accurate, precise, and robust than the conventional analytical method. The amount of rhein and aloe-emodin was higher in the UBE of commercial Rhubarb and Rhubarb plant extract over their TE. For the simultaneous quantification of rhein and aloe-emodin in the TE and UBE of marketed Rhubarb and Rhubarb plant extract, the sustainable analytical method was superior to the conventional analytical method. The AGREE index for the sustainable reverse-phase and conventional normal-phase HPTLC methods was determined to be 0.78 and 0.49, respectively, indicating an excellent greenness profile of the sustainable reverse-phase HPTLC method over the conventional normal-phase HPTLC approach. The sustainable analytical method was found to be superior to the conventional analytical method based on these results. [ABSTRACT FROM AUTHOR]

Human has excellent motor capability and performance in conducting various manipulation tasks. During some tasks such as tightening/loosening a screw with a screwdriver, the motion is accompanied by force exertion to the environment (that is, constrained motion). To obtain natural human-robot interaction (HRI) as human interacts/collaborates with the environment, decoding the human's movement intention in a way of motion and interaction force is meaningful for robots to carry out such constrained tasks. This paper proposes a long shortterm memory (LSTM) -based decoding method for the simultaneous estimation of human motion and interactive force from muscle activities represented by surface electromyography (sEMG) signals. The sEMG recorded from the muscles of forearm is used to decode human's movement intention. In order to extract smooth features from non-stationary sEMG signals, Bayesian filter is applied instead of traditional time-domain feature extraction method. From the real-time experiments on eight subjects, the LSTM-based decoding method represents high accuracy of motion estimation (91.7%) and force estimation (96.1%) despite of the existence of muscle coupling and non-stationary mapping between muscle activities and motion/interaction force during such constrained tasks. It indicates that the estimated motion and interaction force can be further applied for HRI in accomplishing constrained tasks. [ABSTRACT FROM AUTHOR]