Reveal the pharmacodynamic substances and mechanism of an edible medicinal plant Rhodiola crenulate in DSS-induced colitis through plasma pharmacochemistry and metabolomics

Rhodiola crenulate is the edible medicinal herbal medicine widely used for altitude sickness in China.Interestingly,our previous work has found that R.crenulate extract(RCE)could significantly improve the pathology associated with dextran sulfate sodium-induced colitis.Thus,the current research aims to reveal the pharmacodynamic material basis of RCE,as well as its mechanism against colitis.The chemical characterization of RCE was performed by UHPLC-HR-MS,through which a total of 88 constituents were identified.Meanwhile,our results also found 29 constituents absorbed into blood and 8 metabolized absorbable compounds.The decreased flavonoids prototype and the elevated sulfated products of phenols were observed under pathophysiological conditions of colitis.The metabolomics study revealed that colitis caused the alternation of fatty acid metabolism,steroid hormone biosynthesis and bile acid metabolism.Correspondingly,RCE could prevent colitis by improving fatty acid metabolism and secondary bile acid metabolism.

Reversed-Phase-HPLC Assay Method for Simultaneous Estimation of Sorbitol, Sodium Lactate, and Sodium Chlorides in Pharmaceutical Formulations and Drug Solution for Infusion

A rapid, straightforward, sensitive, efficient, and cost-effective reverse-phase high-performance liquid chromatographic method was employed for the simultaneous determination of Sorbitol, Sodium Lactate, and Chlorides in a drug solution for infusion. Sorbitol, Sodium lactate, and Chloride are all officially recognized in the USP monograph. Assay methods are provided through various techniques, with titrations being ineffective for trace-level quantification. Alternatively, IC, AAS, and ICP-MS, though highly accurate, are costly and often unavailable to most testing facilities. When considering methods, it’s important to prioritize both quality control requirements and user-friendly techniques. A simple HPLC simultaneous method was developed for the quantification of Chlorides, Sorbitol, and Sodium Lactate with a shorter run time. The separation utilized a Shimpack SCR-102(H) ion exclusion analytical column (7.9 mm × 300 mm, 7 μm), with a flow rate of 0.6 mL per min. The column compartment temperature was maintained at 40°C, and the injection volume was set at 10 μL, with detection at 200 nm. All measurements were conducted in a 0.1% solution of phosphoric acid. The analytical curves demonstrated linearity (r > 0.9999) in the concentration range of 0.79 to 3.8 mg per mL for Sodium Lactate (SL), 0.16 to 0.79 mg per mL for Sodium Chloride (SC), and 1.5 to 7.2 mg per mL for Sorbitol. Validation of the developed method followed the guidelines of the International Conference on Harmonization (ICH Q2B) and USP. The method exhibited precision, robustness, accuracy, and selectivity. In accelerated stability testing over 6 months, no significant variations were observed in organoleptic analysis and pH. Consequently, the developed method is deemed suitable for routine quality control analyses, enabling the simultaneous determination of Sodium Lactate, Sodium Chloride, and Sorbitol in pharmaceutical formulations and infusions.

Use of subcutaneous tocilizumab to prepare intravenous solutions for COVID-19 emergency shortage:Comparative analytical study of physicochemical quality attributes

COVID-19,a disease caused by the novel coronavirus SARS-Co V-2,has produced a serious emergency for global public health,placing enormous stress on national health systems in many countries.Several studies suggest that cytokine storms(interleukins)may play an important role in severe cases of COVID-19.Neutralizing key inflammatory factors in cytokine release syndrome(CRS)could therefore be of great value in reducing the mortality rate.Tocilizumab(TCZ)in its intravenous(IV)form of administration-Ro Actemra?20 mg/m L(Roche)-is indicated for treatment of severe CRS patients.Preliminary investigations have concluded that inhibition of IL-6 with TCZ appears to be efficacious and safe,with several ongoing clinical trials.This has led to a huge increase in demand for IV TCZ for treating severe COVID-19 patients in hospitals,which has resulted in drug shortages.Here,we present a comparability study assessing the main critical physicochemical attributes of TCZ solutions used for infusion,at 6 mg/m L and 4 mg/m L,prepared from Ro Actemra?20 mg/m L(IV form)and from Ro Actemra?162 mg(0.9 m L solution pre-filled syringe,subcutaneous(SC)form),to evaluate the use of the latter for preparing clinical solutions required for IV administration,so that in a situation of shortage of the IV medicine,the SC form could be used to prepare the solutions for IV delivery of TCZ.It is important to remember that during the current pandemic all the medicines are used off-label,since none of them has yet been approved for the treatment of COVID-19.

Numerical Modeling of Three-Phase Mass Transition with an Application in Atmospheric Chemistry

This work presents a software tool for modeling of mass transfer physicochemical processes occurring in the atmosphere. The implemented algorithms provide an efficient theoretical frame for the interpretation of the results obtained from Coated Wall Flow Tube (CWFT) reactor experiments, which is one of the most adequate techniques to study heterogeneous kinetics. The numerical simulations are based on the fundamental Langmuir adsorption theory by ordinary differential equations and the second Fick’s law described by partial differential equations. The main application of the system is to estimate the basic parameters that characterize the processes. The best parameter estimation is found by minimizing the difference between experimental signals from the CWFT reactors and the obtained numerical simulations. A numerical example for an experimental data fit is given.

SPME as a green sample-preparation technique for the monitoring of phytocannabinoids and endocannabinoids in complex matrices

The endocannabinoid system(ECS),particularly its signaling pathways and ligands,has garnered considerable interest in recent years.Along with clinical work investigating the ECS’functions,including its role in the development of neurological and inflammatory conditions,much research has focused on developing analytical protocols enabling the precise monitoring of the levels and metabolism of the most potent ECS ligands:exogenous phytocannabinoids(PCs)and endogenous cannabinoids(endocannabinoids,ECs).Solid-phase microextraction(SPME)is an advanced,non-exhaustive sample-preparation technique that facilitates the precise and efficient isolation of trace amounts of analytes,thus making it appealing for the analysis of PCs and ECs in complex matrices of plant and animal/human origin.In this paper,we review recent forensic medicine and toxicological studies wherein SPME has been applied to monitor levels of PCs and ECs in complex matrices,determine their effects on organism physiology,and assess their role in the development of several diseases.

Effects of combined cannabidiol(CBD)and hops(Humulus lupulus)terpene extract treatment on RAW 264.7 macrophage viability and inflammatory markers

This study investigates the potential of cannabidiol(CBD),one major cannabinoid of the plant Cannabis sativa,alone and in combination with a terpene-enriched extract from Humulus lupulus(“Hops 1”),on the LPS-response of RAW 264.7 macrophages as an established in vitro model of inflammation.With the present study,we could support earlier findings of the anti-inflammatory potential of CBD,which showed a dose-dependent[0-5μM]reduction in nitric oxide and tumor necrosis factor-alpha(TNF-α)released by LPS-stimulated RAW 264.7 macrophages.Moreover,we observed an additive anti-inflammatory effect after combined CBD[5μM]and hops extract[40μg/mL]treatment.The combination of CBD and Hops 1 showed effects in LPS-stimulated RAW 264.7 cells superior to the single sub-stance treatments and akin to the control hydrocortisone.Furthermore,cellular CBD uptake increased dose-depend-ently in the presence of terpenes from Hops 1 extract.The anti-inflammatory effect of CBD and its cellular uptake positively correlated with terpene concentration,as indicated by comparison with a hemp extract containing both CBD and terpenes.These findings may contribute to the postulations for the so-called“entourage effect”between cannabinoids and terpenes and support the potential of CBD combined with phytomolecules from a non-cannabi-noid source,such as hops,for the treatment of inflammatory diseases.

Anti-diabetic potential of apigenin,luteolin,and baicalein via partially activating PI3K/Akt/GLUT-4 signaling pathways in insulin-resistant HepG2 cells

Dietary flavonoids are abundant in natural plants and possess multiple pharmacological and nutritional activities.In this study,apigenin,luteolin,and baicalein were chosen to evaluate their anti-diabetic effect in high-glucose and dexamethasone induced insulin-resistant(IR)HepG2 cells.All flavonoids improves the glucose consumption and glycogen synthesis abilities in IR-HepG2 cells via activating glucose transporter protein 4(GLUT4)and phosphor-glycogen synthase kinase(GSK-3β).These fl avonoids signifi cantly inhibited the production of reactive oxygen species(ROS)and advanced glycation end-products(AGEs),which were closely related to the suppression of the phosphorylation form of NF-κB and P65.The expression levels of insulin receptor substrate-1(IRS-1),insulin receptor substrate-2(IRS-2)and phosphatidylinositol 3-kinase(PI3K)/protein kinase B(Akt)pathway in IR-HepG2 cells were all partially activated by the fl avonoids,with variable effects.Furthermore,the intracellular metabolic conditions of the fl avonoids were also evaluated.

Phytochemical composition and toxicity assessment of Ammi majus L.

Objective:To assess the acute and subacute toxicity as well as the phytochemical composition of two extracts and three fractions of Ammi majus L.Methods:The aqueous extracts were prepared separately by maceration for 48 h and by infusion for 1 h,while the fractions were prepared by the Soxhlet extractor,successively employing cyclohexane,ethyl acetate,and ethanol.The acute toxicity study was carried out in accordance with the OECD N°423 guideline at a single dose(2000 mg/kg)in mice for 14 days.The subacute toxicity study was performed by a daily oral administration of 250 mg/kg 2 for 10 d and 100 mg/kg doses for 28 d.Phytochemical screening was performed using staining and precipitation reactions,while the chemical characterization of some analytes was detected by HPLC-MS/MS analysis.Results:In the acute toxicity study,no signs of toxicity such as convulsion,salivation,diarrhea,sleep and coma were observed during 30 minutes and 14 days,so the lethal dose was higher than 2000 mg/kg for each extract and fraction.The subacute toxicity results showed that at a dose of 250 mg/kg,61.10%of the animals died and the rest developed morbidity.On the other hand,at a dose of 100 mg/kg,all the animals were still alive after 28 days,with no morbidity and the biochemical parameters were normal with no abnormalities in the liver,kidneys and pancreas.Phytochemical screening indicated the presence of flavonoids,tannins,coumarins,and free quinones and the absence of alkaloids and anthocyanins.Conclusions:The extracts and fractions of Ammi majus L.are not toxic in the short and long term with a varied chemical composition.Toxicological tests on animals other than rodents and in the long term(more than 28 days)are needed to further confirm the safety of Ammi majus extracts.

Evaluation of serum catnepsin B and D in relation to diniGopatnological staging of colorectal cancer

AIM: Proteolytic degradation of the extracellular matrix facilitates cancer invasion and promotes metastasis. The study aims at evaluation of preoperative and postoperative serum cathepsins B and D levels in correlation with selected anatomoclinical features of colorectal cancer.METHODS: Blood samples were collected from 63colorectal cancer patients before curative operation of the tumor 10 d later. Blood that was obtained from 20healthy volunteers, served as a control. The activity of cathepsin B was measured with Bz-DL-arginine-pNA as a substrate at pH 6.0, while cathepsin D activity was determined with urea-denatured hemoglobin (pH 4.0).RESULTS: The preoperative and postoperative activities of cathepsin B were significantly (P＜0.00001) lower in serum of colorectal cancer patients than in control group.However, postoperative values of this protease were significantly increased in comparison with preoperative ones (P = 0.031). Activity of cathepsin D appeared to be significantly higher in colorectal cancer sera (P＜0.00001)compared with controls. No statistically significant differences between preoperative and postoperative activity of cathepsin D were noted (P = 0.09). We revealed a strong linkage of cathepsins' levels with lymph node status and pT stage of colorectal cancer.CONCLUSION: Blood serum activities of cathepsin B and D depend on the time of sampling, tumor size and lymph node involvement. Significantly, increased activity of cathepsin D could indicate a malignant condition of the large intestine. In our work, the serum postoperative decrease of cathepsin B activity appears as an obvious concomitant of local lymph node metastasis-the wellknown clinicopathological feature of poor prognosis.

Sensitive Voltammetric Determination of Captopril Using a Carbon Paste Electrode Modified with Nano-TiO_2/Ferrocene Carboxylic Acid

A carbon paste electrode (CPE) modified with ferrocene carboxylic acid (FcCA) and TiO2 nanoparticles was constructed by incorporating TiO2 nanoparticles and ferrocene carboxylic acid into the carbon paste matrix. The electrochemical behavior of captopril (CAP) at the surface of the modified electrode was investigated using electroanalytical methods. The modified electrode showed excellent electrocatalytic activity for the oxidation of CAP in aqueous solutions at physiological pH values. Cyclic voltammetric curves showed that the oxidation of CAP at the surface of the modified electrode reduced its overpotential by more than 290 mV. The modified electrode was used for detecting captopril using cyclic voltammetry and square wave voltammetry techniques. A calibration curve in the range of 0.03 to 2400 μmol/L was obtained that had a detection limit of 0.0096 μmol/L (3?) under the optimized conditions. The modified electrode was successfully used for the determination of captopril in pharmaceutical and biological samples.

Extracellular synthesis of silver nanoparticles using dried leaves of pongamia pinnata(L) pierre

Extract of oven dried leaves of Pongamia pinnata(L) Pierre was used for the synthesis of silver nanoparticles. Stable and crystalline silver nanoparticles were formed by the treatment of aqueous solution of AgNO_3(1m M) with dried leaf extract of Pongamia pinnata(L) Pierre. UV-visible spectroscopy studies were carried out to quantify the formation of silver nanoparticles. Transmission electron microscopy, X-ray diffraction and Fourier transform infrared spectroscopy were used to characterize the silver nanoparticles. TEM image divulges that silver nanoparticles are quite polydispersed, the size ranging from 20 nm to 50 nm with an average of 38 nm. Water soluble heterocyclic compounds such as flavones were mainly responsible for the reduction and stabilization of the nanoparticles. Silver nanoparticles were effective against Escherichia coli(ATCC 8739), Staphylococcus aureus(ATCC 6538p), Pseudomonas aeruginosa(ATCC 9027) and Klebsiella pneumoniae(clinical isolate). The move towards extracellular synthesis using dried biomass appears to be cost effective, eco-friendly to the conventional methods of nanoparticles synthesis.

S-Nitroso-N-acetyl-L-cysteine ethyl ester(SNACET) and N-acetyl-L-cysteine ethyl ester(NACET)–Cysteine-based drug candidates with unique pharmacological profiles for oral use as NO, H_2S and GSH suppliers and as antioxidants: Results and overview

S-Nitrosothiols or thionitrites with the general formula RSNO are formally composed of the nitrosyl cation(NOt) and a thiolate(RSà), the base of the corresponding acids RSH. The smallest S-nitrosothiol is HSNO and derives from hydrogen sulfide(HSH, H_2S). The most common physiological S-nitrosothiols are derived from the amino acid L-cysteine(Cys SH). Thus, the simplest S-nitrosothiol is S-nitroso-L-cysteine(Cys SNO). Cys SNO is a spontaneous potent donor of nitric oxide(NO) which activates soluble guanylyl cyclase to form cyclic guanosine monophosphate(c GMP). This activation is associated with multiple biological actions that include relaxation of smooth muscle cells and inhibition of platelet aggregation.Like NO, Cys SNO is a short-lived species and occurs physiologically at concentrations around 1 n M in human blood. Cys SNO can be formed from Cys SH and higher oxides of NO including nitrous acid(HONO)and its anhydride(N_2O_3). The most characteristic feature of RSNO is the S-transnitrosation reaction by which the NOtgroup is reversibly transferred to another thiolate. By this way numerous RSNO can be formed such as the low-molecular-mass S-nitroso-N-acetyl-L-cysteine(SNAC) and S-nitroso-glutathione(GSNO), and the high-molecular-mass S-nitrosol-L-cysteine hemoglobin(Hb Cys SNO) present in erythrocytes and S-nitrosol-L-cysteine albumin(Alb Cys SNO) present in plasma at concentrations of the order of 200 n M. All above mentioned RSNO exert NO-related biological activity, but they must be administered intravenously. This important drawback can be overcome by lipophilic charge-free RSNO.Thus, we prepared the ethyl ester of SNAC, the S-nitroso-N-acetyl-L-cysteine ethyl ester(SNACET), from synthetic N-acetyl-L-cysteine ethyl ester(NACET). Both NACET and SNACET have improved pharmacological features over N-acetyl-L-cysteine(NAC) and S-nitroso-N-acetyl-L-cysteine(SNAC), respectively,including higher oral bioavailability. SNACET exerts NO-related activities which can be utilized in the urogenital tract and in the cardiovascular system. NACET, with high oral bioavailability, is a strong antioxidant and abundant precursor of GSH, unlike its free acid N-acetyl-L-cysteine(NAC). Here, we review the chemical and pharmacological properties of SNACET and NACET as well as their analytical chemistry.We also report new results from the ingestion of S-[^(15) N]nitroso-N-acetyl-L-cysteine ethyl ester(S^(15) NACET) demonstrating the favorable pharmacological profile of SNACET.

Comparing different domains of analysis for the characterisation of N-glycans on monoclonal antibodies

With the size of the biopharmaceutical market exponentially increasing,there is an aligned growth in the importance of data-rich analyses,not only to assess drug product safety but also to assist drug development driven by the deeper understanding of structure/function relationships.In monoclonal antibodies,many functions are regulated by N-glycans present in the constant region of the heavy chains and their mechanisms of action are not completely known.The importance of their function focuses analytical research efforts on the development of robust,accurate and fast methods to support drug development and quality control.Released N-glycan analysis is considered as the gold standard for glycosylation characterisation;however,it is not the only method for quantitative analysis of glycoform heterogeneity.In this study,ten different analytical workflows for N-glycan analysis were compared using four monoclonal antibodies.While observing good comparability between the quantitative results generated,it was possible to appreciate the advantages and disadvantages of each technique and to summarise all the observations to guide the choice of the most appropriate analytical workflow according to application and the desired depth of data generated.

Validated spectrofluorimetric method for the determination of atorvastatin in pharmaceutical preparations

A rapid,sensitive and simple spectrofluorimetric method was developed for the estimation of atorvastatin.In this method,the native fluorescence characteristics of atorvastatin have been studied in both acidic and basic media.High sensitivity was obtained with 5% acetic acid at 389 nm using 276 nm for excitation.Regression analysis showed a good correlation coefficient(r=0.9995) between fluorescence intensity and concentration over the range of 1.5-4 mg/mL with detection limit of 0.012 mg/mL.The proposed method was successfully applied to the analysis of atorvastatin in pure and pharmaceutical dosage forms with average recovery of 100.2970.47%.The results were compared favorably with those of the reported method.

A rapid synthesis of high surface area PdRu nanosponges:Composition-dependent electrocatalytic activity for formic acid oxidation

Here, Pd Ru nanoparticle networks（NPNs） with various compositions were synthesized through an inexpensive method in water as a green solvent, at different ratios of the H;PdCl;and RuCl;precursors. This is a fast, room temperature and surfactant free strategy which is able to form high surface area metal nanosponges with a three-dimensional（3D） porous structure. The structure of as-prepared nanosponges was characterized using the techniques of field emission scanning electron microscopy（FESEM）, energy dispersive spectroscopy（EDS） and cyclic voltammetry（CV）. Then, the electrocatalytic activities of Pd Ru NPNs towards formic acid oxidation were examined by electrochemical measurements including CV,chronoamperometry, and electrochemical impedance spectroscopy（EIS）. Based on studies, it was found that the current density of formic acid oxidation（FAO） is strongly dependent on the composition of Pd Ru NPNs. The best performance was realized for Pd;Ru;NPNs compared to monometallic Pd counterpart and other bimetallic NPNs which might be ascribed to the role of Ru in the decrease of CO adsorption strength on the catalyst and consequently the priority of formic acid oxidation through the direct pathway. The Pd;Ru;NPNs also showed the maximum current density and stability in chronoamperometric measurements. In addition, comparative studies were performed between as-prepared NPNs and CNTs-supported Pd nanoparticles（Pd NPs/CNTs）. The present results demonstrated the unique structural advantages of NPNs compared to individual Pd NPs supported on the CNT which leads to the promising performance of NPNs as supportless catalysts for the oxidation of formic acid.

Controlling the rate of degradation of Mg using magnesium fluoride and magnesium fluoride-magnesium phosphate duplex coatings

The thin and porous Fluoride Conversion Coating FCC with many cracks could not offer a significant improvement in corrosion resistance for Mg. Magnesium phosphate coating improves the corrosion resistance of Mg, good bioactivity, promotes cell viability and cyto-compatibility and exhibits antibacterial activity. However, rapid dissolution in Mg in acidic magnesium phosphate containing solutions leads to the development of an inhomogeneous coating. The present study attempts to prevent the excessive dissolution of Mg by forming a fluoride conversion coating as a pre-treatment in the first stage followed by deposition of magnesium phosphate coating in the second stage to develop magnesium fluoride-magnesium phosphate duplex coatings. The morphological features, structural characteristics, nature of functional groups, corrosion behavior in Hanks’ balanced salt solution and bioactivity in simulated body fluid are assessed to ascertain the suitability of the magnesium fluoride-magnesium phosphate duplex coating in controlling the rate of degradation of Mg and improving its bioactivity using uncoated Mg and fluoride conversion coated Mg as reference. The findings of the study reveal that the magnesium fluoride-magnesium phosphate duplex coating could offer an excellent corrosion resistance and improve the bioactivity of Mg.

Nanobiocomposite Electrochemical Biosensor Utilizing Synergic Action of Neutral Red Functionalized Carbon Nanotubes

An amperometric hydrogen peroxide biosensor using a nanobiocomposite based on neutral red modified carbon nanotubes and co-immobilized glucose oxidase and horseradish peroxidase is reported. Modification of the nanobiocomposite electrode with neutral red resulted in a sensitive, low-cost and reliable H_2O_2 sensor. The use of carbon nanotubes, as the conductive part of the composite, facilitated fast electron transfer rates. The biosensor was characterized for the influence of p H, potential and temperature. A remarkable feature of the biosensor is the detection of H_2O_2 at low applied potentials where the noise level and interferences are minimal. The sensor has a fast steady-state measuring time of 10 s with a quick response(2 s). The biosensor showed a linear range from 15 n M to 45 m M of H_2O_2 and a detection limit of 5 n M. Nafion, which is used as a binder, makes the determination free from other electroactive substances. The repeatability, reproducibility,stability and analytical performance of the sensor are very good.

Concentration, Distribution and Comparison of Total and Bioavailable Heavy Metals in Top Soils of Bonab District in Zanjan Province

Heavy metal contamination of soils is a widespread problem in Zanjan province located in North West Iran due to natural pedo geochemical background and anthropogenic sources. The province is highly polluted by some heavy metals due to the presence of mineral resources notably Lead and Zinc, their improper utilization, and also the development of a number of related industries. Bonab district was selected for detail study and the objectives of the study were set to evaluate the total as well as bioavailable fraction of heavy metals in surficial soils within the studied area. 72 soil samples were collected and analyzed for heavy metal contamination by Atomic Absorption Spectrometry (AAS). The obtained results when compared with WHO and USEPA standards show a very high concentration of some toxic metals. Soils were basically polluted by Pb, Zn, Cu, and Cd. Bioavailable fraction of studied metals were also measured with formation of metal complex with Diethylene tri amine penta acetic acid (DTPA) agent. To find the share of the anthropogenic sources in the contamination of soils, the Enrichment factor (EF) and Geological Accumulation Index were measured and the distribution maps were drawn using Arc GIS (9.3). Highest concentrations of some toxic metals were found as isolated patches around the Bonab Industrial Town as well as within and around the most populated areas of the district notably Zanjan city indicating its anthropogenic origin.

Sugar Cane （Saccharum officinarum L.） Analysis through Biospeckle and Spectroscopy （NIR）

The objective of this paper was to evaluate the sugar and water content in sugar cane samples by means of twonon-destructive techniques in comparison with conventional methods. One non-destructive technique is the Biospeckle, aninteraction between the laser and the biological material which provides information about the material. The other technique is thenear infrared spectroscopy （NIR）. The Biospeckle technique has been constantly used in agricultural engineering. In this paper, therelation between the water and the sugar contents were obtained. The results for the Biospeckle were acquired through the moment ofinertia （MI）. The data acquired through already consolidated methodologies were used to quantify the samples＇ water and sugarcontents, correlating to the spectroscopy results and also to the Biospeckle. It was obtained a high determination coefficient （R^2 =0.9287） between the predicted Brix by the model generated by NIR spectroscopy and Brix measured by refractometer. It was alsopossible to differentiate the water contents of the sugar cane samples both externally lit （husk） and internally lit （cut） by Biospeckleanalysis through the calculation of MI. It is possible to evaluate the water content and the sugar content in samples combiningBiospeckle and NIR spectroscopy, which are non-invasive and non-destructive methods.

Two spectrophotometric methods for simultaneous determination of some antihyperlipidemic drugs

Two simple, accurate, precise and economic spectrophotometric methods have been developed for simultaneous determination of Atorvastatin calcium (ATR) and Ezetimibe (EZ) in their bulk powder and pharmaceutical dosage form. Method (I) is based on dual wavelength analysis while method (II) is the mean centering of ratio spectra spectrophotometric (MCR) method. In method (I), two wavelengths were selected for each drug in such a way that the difference in absorbance was zero for the second drug. At wavelengths 226.6 and 244 nm EZ had equal absorbance values; therefore, these two wavelengths have been used to determine ATR; on a similar basis 228.6 and 262.8 nm were selected to determine EZ in their binary mixtures. In method II, the absorption spectra of both ATR and EZ with different concentrations were recorded over the range 200-350, divided by the spectrum of suitable divisor of both ATR and EZ and then the obtained ratio spectra were mean centered. The concentrations of active components were then determined from the calibration graphs obtained by measuring the amplitudes at 215-260 nm (peak to peak) for both ATR and EZ. Accuracy and precision of the developed methods have been tested; in addition recovery studies have been carried out in order to confirm their accuracy. On the other hand, selectivities of the methods were tested by application for determination of different synthetic mixtures containing different ratios of the studied drugs. The developed methods have been successfully used for determination of ATR and EZ in their combined dosage form and statistical comparison of the developed methods with the reported spectrophotometric one using F and Student’s t-tests showed no significant difference regarding both accuracy and precision.