Drug analysis

s The goal of this study was to develop and validate a liquid chromatography (LC) method for the rapid determination of dipyrone (metamizole sodium) in solid and liquid formulations. Samples were extracted with water and filtered prior to LC analysis. The analytical procedure involved reversed phase LC with a Zorbax SB C 18 column (5 m particle size, 4.6 mm × 250 mm i.d.), isoctratic methanol/water (80/20, v/v) mobile phase with UV detection at 254 nm. The flow rate was 1 mL min −1 , injection volume was 100 L and retention time of dipyrone was 3.3 min. The method was validated with respect to linearity, precision and accuracy. Calibration curves were linear in the range 0.5–100 g mL −1 for analyte and the recoveries at three levels (10, 15 and 25 g mL −1) ranged from 93 to 100%. All results for dipyrone were confirmed by liquid chromatography–mass spectrometry (LC–MS) and 1 H nuclear magnetic resonance (NMR) spectroscopy. Due to its simplicity and accuracy, the assay method is suitable for routine analysis of both solid and liquid formulations and seven retail samples were analyzed using the validated method.

Laboratory activity is an important part of chemistry learning, but cookbook instructions is still commonly used. However, the activity with that way do not improve students thinking skill, especially students creativity. This study aims to improve high school students creativity through inquiry-based laboratory on drugs analysis activity. Acid-base titration is used to be method for drugs analysis involving a color changing indicator. The following tools were used to assess the activity achievement: creative thinking test on acid base titration, creative attitude and action observation sheets , questionnaire of inquiry-based lab activities, and interviews. The results showed that the inquiry-based laboratory activity improving students creative thinking, creative attitude and creative action. The students reacted positively to this teaching strategy as demonstrated by results from questionnaire responses and interviews. This result is expected to help teachers to overcome the shortcomings in other laboratory learning.

Methocarbamol is formulated with Ibuprofen for treatment of alleviated pain associated with muscle spasm. This manuscript describes a sensitive and selective first derivative synchronous spectrofluorimetric method for simultaneous determination of both drugs. Factors affecting method selectivity were studied where best results were obtained upon using Δ λ = 20 and water as a solvent. Methocartbamol was determined at 283 nm while Ibuprofen at 285.5 nm in the concentration ranges of 0.4-5 and 0.2-4.8 μg/mL, respectively. The applicability of the proposed method was ascertained by application to different laboratory prepared mixtures and marketed formulation. The high sensitivity achieved by the proposed method permitted its application for determination of the drugs in human plasma spiked with pure drugs and their combined tablets. The proposed method showed no significant difference when compared with the reported HPLC method using student's t-test and F-ratio test.

A simple precise specific sensitive and accurate stability indicating RP-HPLC method for determination of cefuroxime Axetil and its degradation products in tablets. The separation was performed on Teknokroma, tracer excel C8 column (15cm x 0.46cm.5μm) using mobile phase consisting of 0.02M potassium dihydrogen phosphate: methanol: Acetonitrile (60: 35: 5 v/v). The flow rate was 1mL/min and detection was monitored at 278nm. The column temperature was set at 35℃. The retention times were 2.4, 11.09, 12.6, 12.6, 14.13, 20.76 and 24.24 minutes for cefuroxime Axetil B, cefuroximeA A, Δ^3-isomers, E-isomer 1 and E-isomer 2, respectively. The calibration curves were found to be linear in the concentration range of 120-312 μg/mL (r2 =0.99964) and 0.24-7.2 μg/mL (r2 =0.9997) at assay level and low-level of cefuroxime Axetil. The percentage recoveries of cefuroxime Axetil at assay level were found to be in the range of 98.54-99.35% and 101.4-103.69% at low-level at 95% confidence limit. The intraday precision was 0.517% and 2.019% at to assay level and low-level of CFA, respectively. The intermediate precisions were 1.102% and 2.273% at assay level and low-level of CFA, respectively.

Simple, sensitive and accurate UV and two visible spectrophotometric methods were developed for the analysis of Empagliflozin in pharmaceutical formulations. Method M1 based on the UV absorption of drug in UV region that shows absorption maxima at 247nm. Method M2 and M3 based on the oxidative coupling reaction of drug with 1 10 phenanthroline and Potassium ferricyanide that shows maximum absorbance at 438nm and 782nm for method M2 and M3 respectively. Linearity range was found to be 2-12µg/ml for UV method [M1], 5-30µg/ml for 1 10 phenanthroline method [M2] and 10-60µg/ml for Potassium ferricyanide method [M3]. The methods were validated as per ICH guidelines. The proposed methods have been applied for the estimation of Empagliflozin in tablets. The developed method was simple, accurate, reliable and economical. The proposed method is specific without and interference of excepients and hence can be used for the routine analysis of Empagliflozin in bulk and in pharmaceutical formulation.

Three novel and distinct agricultural waste materials, viz., Casuarinas fruit powder (CFP), sorghum stem powder (SSP) and banana stem powder (BSP) were used as low cost adsorbents for the removal of toxic copper(II) from aqueous solutions. Acid treated adsorbents were characterized by SEM, EDX and FTIR. Different factors effecting adsorption capacity were analyzed and the effi ciency order was BSP>SSP>CFP. Based on the extent of compatibility to Freundlich/Langmuir/D-R/Temkin adsorption isotherm and different models (pseudo-fi rst and second order, Boyd, Weber's and Elovich), chemisorption primarily involved in the case of CFP and SSP, whereas, simultaneous occurrence of chemisorption and physisorption was proposed in the case of BSP. Based on the observations, it was proposed that three kinetic stages involve in adsorption process viz., diffusion of sorbate to sorbent, intra particle diffusion and then establishment of equilibrium. These adsorbents have promising role towards removal of Cu(II) from industrial wastewater to contribute environmental protection.

A rapid, selective and stability-indicating high performance
thin layer chromatographic method was developed and validated
for the simultaneous estimation of risperidone and trihexyphenidyl
hydrochloride in combined tablet dosage form. Risperidone and
trihexyphenidyl hydrochloride were chromatographed on silica gel
60 F254 TLC plate using toluene: methanol: acetone: triethylamine
(5:3:1:0.2, v/v/v/v) as the mobile phase and spectro densitometric
scanning was performed at a wavelength of 230 nm using a Camag
TLC Scanner III. This system was found to give compact spots for
both risperidone (Rf 0.42 ± 0.02) and trihexyphenidyl
hydrochloride (Rf 0.68 ± 0.01). The polynomial regression data for
the calibration plots showed good linear relationship with
r2=0.9995± 0.0051 in the concentration range of 50-1000 ng/spot
for risperidone and 100-1200 ng/spot for trihexyphenidyl
hydrochloride with r2=0.9991± 0.0031. The method was validated
in terms of linearity, accuracy, precision, recovery and specificity.
The LOD and LOD for the risperidone were found to be 10± 0.51
and 50±1.05 ng/spot, respectively and for trihexyphenidyl
hydrochloride 35 ± 0.63 and 100±1.12 ng/spot, respectively. Both
the drugs were subjected to acid, alkali, hydrolysis, oxidation, dry
heat and photolytic degradation. The degradation studies indicated,
risperidone showed degradation in acid, alkali, oxidative and dry
heat while trihexyphenidyl hydrochloride showed degradation in
acid and H2O2. The degradation products were well resolved from
the pure drug with significant differences in their retention time
values. This method can be successfully employed for simultaneous
quantitative analysis of risperidone and trihexyphenidyl
hydrochloride in bulk drugs and formulations.

Accurate, selective and sensitive spectrophotometric methods have been developed and validated for simultaneous determination of Cinnarizine and Domperidone, a binary mixture with overlapping spectra, without preliminary separation. These methods include area under the curve (AUC) and dual wavelength spectrophotometry. For the AUC method, the area under curve of mixture solutions in the wavelength ranges 241–258 nm and 280–292 nm were selected for determination of Cinnarizine and Domperidone and by applying Cramer’s rule, concentration of each drug was obtained. In dual wavelength method, two wavelengths were selected for each drug in a way so that the difference in absorbance is zero for another drug. Domperidone shows equal absorbance at 240.2 nm and 273.2 nm, where the differences in absorbance were measured for the determination of Cinnarizine. Similarly, differences in absorbance at 230.8 nm and 259.2 nm were measured for determination of Domperidone. The proposed methods were applied for determination of Cinnarizine and Domperidone over the concentration ranges of 2–20 and 2–22 μg mL−1, respectively. The suggested methods were validated as per USP guidelines and the results revealed that they are reliable, reproducible and precise for routine use with short analysis time. The results obtained by the proposed methods were statistically compared to the reported method, and there was no significant difference between them regarding both accuracy and precision.

The study evaluated the quality control parameters of
different brands of griseofulvin tablets sold in Nigerian to
determine compliance with the official standards and control
distribution of fake and counterfeit drugs. The five brands:
Unicin®, Grufin®, Fesovin®, Griseomed®, and Grenin®
(designated as brands A1-A5) were evaluated for hardness,
friability, disintegration time, weight uniformity, dissolution
rate and assay of active ingredient by standard assay
methods. The dissolution rate and disintegration time were
determined in simulated gastric fluid (SGF) and simulated
intestinal fluid (SIF) without enzymes. All brands complied
with the official requirements for uniformity of weight (≤ 5 %
deviation) and assay of active ingredients (95-105 %), and
some non-official requirement for hardness (≤ 5 kgF),
however, brand A4 failed in the hardness test (hardness 5.10
kgF). The disintegration times were higher in SIF for brands
A3 to A5 than in SGF; all brands except A3 disintegrated with
15 minutes which also affected the dissolution and release of
griseofulvin from the tablets. The dissolution profile of the
different brands showed more than 50 % release within 20-30
minutes and 30-40 minutes in SIF and SGF respectively. The
results showed that the tablets were of good quality relatively
and the methods used in the evaluation was simple, effective
and serves as good tools to ensure quality in the production,
distribution, storage, prescription, dispensing as well as
consumption of griseofulvin tablets in Nigeria

Accurate, selective and sensitive stability indicating high performance thin layer chromatographic (HPTLC) method was developed and validated for determination of Metopimazine (MPZ) in presence of its degradation products; including the oxidative degradation product (Deg I) and the alkaline hydrolysis degradation product (Deg II; formerly reported as acid metabolite). The proposed method was applied for analysis of MPZ in pure form, pharmaceutical formulation (tablets) and human plasma over the concentration range of 0.4–1.4 μg band−1 with accuracy of mean percentage recovery 100.10 ± 0.941. The method depends on separation of MPZ from its degradation products on HPTLC silica gel 60 F254 plates using chloroform–methanol–ammonia (12:2:0.1, by volume) as developing system followed by densitometric measurement of bands at 254 nm. The method was validated according to ICH guidelines. The degradation products were well resolved from the pure drug with significantly different Rf values (MPZ, Rf = 0.58, Deg I, Rf = 0.35 and Deg II, Rf = 0.03). The results obtained by the proposed method were statistically compared to the reported HPTLC method, and there was no significant difference between them regarding both accuracy and precision; indicating the ability of the proposed method to be used for routine analysis of drug product.

A simple, precise, specific, sensitive and accurate stability indicating RP-HPLC method for determination of prednisolone and its degradation products in tablets. The separation was performed on teknokroma, tracer excel C18 column (15cmx 0.46 cm. 5μm) using mobile phase consisting ofwater: tetrahydrofuran: acetonitrile in ratio (75: 15: 10). The flow rate was 1mL/min and detection was set at 254 nm. The column temperature was set at 450. The retention times were 7.5, 9.98 and 10.7 for prednisone, prednisolone and hydrocortisone respectively. The calibration curves were found to be linear in the concentration range of 25-75 μg/mL (r2 =0.9998) and 0.25-7.2 μg/mL (r2 =0.9999) at assay level and low-level of prednisolone.
The percentage recoveries of prednisolone found to be in the range of 99.3-99.99% at assay level and 98.77-99.75%at low-level respectively at 95% confidence limit. The intraday precision was 0.424% and 0.501% at assay level and low-level, respectively. The intermediate precision was 0.44% and 0.634% at assay level and low-level, respectively.
Introduction
Prednisolone is chemically designated as 11β, 17α, 21-trihydroxypregna-1, 4-diene-3, 20-dione.
Prednisolone is a glucocorticoid and widely used as a potent anti-inflammatory, anti-allergic and immunosuppressive drug.
Estimations of prednisolone have been described by spectrophotometry [1-9]. A HPLC method have been developed for the assay of prednisolone [7,10,17]. The pharmacopeial methods for the determination of prednisolone and its degradation products in tablets are available. In the B.P pharmacopoeia, the mobile phase consisted of methanol: water (58: 42) for the assay. For related substances, the mobile phase composed of the mixture of water and tetrahydrofuran (780: 220) [18].
In USP pharmacopoeia, the mobile phase composed of a mixture of butyl chloride, water-saturated butylchloride, tetrahydrofuran, methanol, glacial acetic acid for assay. For related substances, the mobile phase composed of mixture of water: ACN and the elution are gradient. In the proposed method, the analysis for assay and degradation product was carried out on single method.
Experimental
Instrumentation
An HPLC system from shimadzu corporation consisting of an LC-20 AT pump, SPD-20 A UV/vis-detector, DGU 20A3, a reodyne injector with 20μL loop. Teknokroma, tracer excel. C18 column (15cm x 0.46cm, 5μm) and C18 column (25cm x 0.46cm, 5μm).
Keywords: Prednisolone; HPLC method; repeatability; precision; Hydrogen peroxide

Sensitive and validated UV-spectrophotometric, chemometric and TLC-densitometric methods were developed for determination of triamterene (TRM) and xipamide (XIP) in their binary mixture, formulated for use as a diuretic, without previous separation. Method A is the isoabsorptive point spectrophotometry, in which TRM concentration alone can be determined at its λ(max) while XIP concentration can be determined by measuring total concentration of TRM and XIP at their isoabsorptive point followed by subtraction. Method B is the ratio subtraction spectrophotometry, where XIP can be determined by dividing the spectrum of the mixture by the spectrum of TRM (as a divisor) followed by subtracting the constant absorbance value of the plateau region, then finally multiplying the produced spectrum by the spectrum of the divisor, while TRM concentration can be determined at its λ(max). Method C is a chemometric-assisted spectrophotometry where classical least squares, principal component regression, and partial least squares were applied. Method D is a TLC-densitometry; this method depends on quantitative densitometric separation of thin layer chromatogram of TRM and XIP using silica gel plates at 254 nm. The proposed methods were successfully applied for the analysis of TRM and XIP in their pharmaceutical formulation and the results were statistically compared with the established HPLC method.

This study compares between unmodified carbon paste (CPE; the paste has no ion pair) and polyvinyl chloride (PVC) membrane selective electrodes that were used in potentiometric determination of ketotifen fumarate (KTF), where sodium tetraphenylborate (NaTPB) was used as titrant. The performance characteristics of these sensors were evaluated according to IUPAC recommendations which reveal a fast, stable, and linear response for KTF over the concentration range of 10 −7 to 10 −2 mol L −1. The electrodes show Nernstian slope value of 52.51±0.20 and 51.51±0.25 mV decade −1 for CPE and PVC membrane electrodes at 30 • C, respectively. The potential is nearly stable over the pH range 3.0–6.0 and 2.0–7.0 for CPE and PVC membrane electrodes, respectively. Selectivity coefficient values towards different inorganic cations, sugars, and amino acids reflect high selectivity of the prepared electrodes. The electrodes responses at different temperatures were also studied, and long operational lifetime of 12 and 5 weeks for CPE and PVC membrane electrodes, respectively, were found. These are used for determination of ketotifen fumarate using potentiometric titration, calibration, and standard addition methods in pure samples, its pharmaceutical preparations (Zaditen tablets), and biological fluid (urine). The direct potentiometric determination of KTF using the proposed sensors gave recoveries % of 98.97 ± 0.53 and 98.62 ± 0.74 with RSD 1.42 and 0.63% for CPE and PVC membrane selective electrodes, respectively. Validation of the method shows suitability of the proposed sensors for use in quality control assessment of KTF. The obtained results were in a good agreement with those obtained using the reported spectrophotometric method.

Petroleum hydrocarbon profiles of water and sediment samples of Algoa Bay in the Eastern Cape Province of South Africa were assessed using standard analytical procedures. Water (from surface and bottom levels) and sediment samples were collected from five locations in the bay from February to June 2016. Extraction of the petroleum hydrocarbons from the water and sediment samples collected was achieved using liquid-liquid and Soxhlet extraction techniques, respectively, followed by column clean up. Target compounds were analytically determined with gas chromatography-flame ionization detector (GC-FID) and quantified by integrating the areas of both the resolved and unresolved components. Physicochemical properties of the water samples were also determined on site using a SeaBird 19plusV2 CTD SBE 55 device. Estimated limit of detection, limit of quantitation and relative standard deviation for the 35 n-alkane standards ranged from 0.06 to 0.13 μg/L, 0.30 to 0.69 μg/L and 3.61 to 8.32%...

A simple, precise, specific, sensitive and accurate stability indicating RP-HPLC method for determination of secnidazole and its degradation products in tablets. The separation was performed on teknokroma, tracer excel C18 column (25cm x 0.46cm.5μm) using mobile phase consisting of water: methanol: acetonitrile in ratio (73: 17: 10). A flow rate was set at 1mL/min; the detection wavelength was set at 228nm. The calibration curves were found to be linear in the concentration range of 50-150/mL (r2 =0.9997) and 0.25-7.5μg/mL (r2 =0.998) at assay level and low-level of secnidazole. The percentage recoveries of secnidazole were 100.76-101.66% and 97.87-102% at assay and low-level, respectively at 95% confidence limit. The intraday precision was 0.553% and 1.35% at assay level and low-level, respectively. The intermediate precision was 0.56% and 3.10% at assay level and low-level, respectively.

Solubilization of poorly water-soluble drugs has been a very important issue in screening studies of new chemical entities as well as in formulation research. A novel, safe and sensitive method of titrimetric estimation has been developed using 2 M sodium saccharin solution (an economic drug) as a hydrotropic solubilizing agent for the quantitative determination of salicylic acid in bulk, a sparingly water-soluble keratolytic drug. There was more than a 15-fold enhancement in aqueous solubility of salicylic acid in 2 M sodium saccharin solution as compared with the solubility in distilled water. The hydrotrope used in this work is freely soluble in water, non toxic and does not interfere in analysis. The results of analysis obtained by the proposed method are comparable with the results of analysis obtained by the Indian Pharmacopoeial method. The proposed method is new, simple, accurate and reproducible. Results of the analysis were validated statistically. Statistical data proved the accuracy, reproducibility and precision of the proposed method.

General information, structure, mechanism of action and metabolites, analysis of the active ingredient of a CNS stimulant drug; Methylphenidate (Ritalin). It was a presentation for our Analytical Toxicology and Chemical Applications in the Spring semester of the 2020-2021 academic year, Ege University

Background : Traditionally Nigella sativa (black seed) has been widely used as a medicinal plant in Unani, Ayurveda and Siddha system of
medicine. Extensive studies have been carried out by various researchers to explore the pharmacological action of black seed oil. The purpose
of this preliminary research work is to establish anti bacterial properties of black seed oil in order to develop a model for curing diabetic ulcers.
Method: This preliminary research work was carried out to find the antibacterial effect of black seed oil against selected human bacterial
strains such as Staphylococcus aureus, Streptococcus pyogenes, Bacillus subtilis, Proteus vulgaris, Escherichia coli and Klebsiella
planticola. Results: The maximum activity was measured for Escherichia coli followed by Streptococcus pyogenes, Staphylococcus aureus
and Proteus vulgaris. However, Bacillus subtilis and Klebsiella planticola have shown resistance against the black seed oil. Conclusion:
The black seed oil has excellent anti bacterial action on par with standard ciprofloxacin drug.

An Acad Bras Cienc (2016) 88 (1) Anais da Academia Brasileira de Ciências (2016) 88(1): 1-15 (Annals of the Brazilian Academy of Sciences) Printed version ABSTRACT An alternative method for the quantifi cation of sulphametoxazole (SMZ) and trimethoprim (TMP) using diffuse refl ectance infrared Fourier-transform spectroscopy (DRIFTS) and partial least square regression (PLS) was developed. Interval Partial Least Square (iPLS) and Synergy Partial Least Square (siPLS) were applied to select a spectral range that provided the lowest prediction error in comparison to the full-spectrum model. Fifteen commercial tablet formulations and forty-nine synthetic samples were used. The ranges of concentration considered were 400 to 900 mg g-1 SMZ and 80 to 240 mg g-1 TMP. Spectral data were recorded between 600 and 4000 cm-1 with a 4 cm-1 resolution by Diffuse Refl ectance Infrared Fourier Transform Spectroscopy (DRIFTS). The proposed procedure was compared to high performance liquid chromatography (HPLC). The results obtained from the root mean square error of prediction (RMSEP), during the validation of the models for samples of sulphamethoxazole (SMZ) and trimethoprim (TMP) using siPLS, demonstrate that this approach is a valid technique for use in quantitative analysis of pharmaceutical formulations. The selected interval algorithm allowed building regression models with minor errors when compared to the full spectrum PLS model. A RMSEP of 13.03 mg g-1 for SMZ and 4.88 mg g-1 for TMP was obtained after the selection the best spectral regions by siPLS., diffuse reflectance infrared Fourier transform spectroscopy, green analytical method, high performance liquid chromatography, interval partial least squares (iPLS), synergy partial least squares (siPLS).

A spectrophotometric kinetic study of Niclosamide alkaline degradation as a function of drug concentration, alkaline concentration and temperature has been established utilizing double divisor-ratio spectra spectrophotometric method. The developed method allowed determination of Niclosamide in presence of its alkaline degradation products; namely; 2-chloro-4-nitro aniline (DEG I) and 5-chloro salicylic acid (DEG II) with characterization of its degradation mechanism. It was found that degradation kinetic of Niclosamide followed pseudo-first order under the established experimental conditions with a degradation rate constant (k) of 0.0829mol/h and half life (t1/2) of 8.35h. The overall degradation rate constant as a function of the temperature under the given conditions obeyed Arrhenius equation where the activation energy was calculated to be 3.41kcal/mol.

Petroleum hydrocarbon profiles of water and sediment samples of Algoa Bay in the Eastern Cape Province of South Africa were assessed using standard analytical procedures. Water (from surface and bottom levels) and sediment samples were collected from five locations in the bay from February to June 2016. Extraction of the petroleum hydrocarbons from the water and sediment samples collected was achieved using liquid-liquid and Soxhlet extraction techniques, respectively, followed by column clean up. Target compounds were analytically determined with gas chromatography-flame ionization detector (GC-FID) and quantified by integrating the areas of both the resolved and unresolved components. Physicochemical properties of the water samples were also determined on site using a SeaBird 19plusV2 CTD SBE 55 device. Estimated limit of detection, limit of quantitation and relative standard deviation for the 35 n-alkane standards ranged from 0.06 to 0.13 μg/L, 0.30 to 0.69 μg/L and 3.61 to 8.32%...

A new, rapid, sensitive and selective method for the spectrophotometric determination of xipamide in pure and dosage forms is proposed. The method is based on the reaction ofxipamide with Fe(III), Cu(II), La(III), UO2(II), Th(IV) and ZrO(II) ions to form stable coloredcomplexes. The formed complexes have maximum absorbance at 500, 390, 335, 445, 325 and 333 nm for Fe(III), Cu(II), La(III), UO2(II), Th(IV) and ZrO(II), respectively. Optimumconditions for determination, stoichometry and stability of the formed complexes have beendetermined. Beer's law is obeyed up to concentration range 54.64-1995.75 mg ml-1 of xipamide with apparent molar absorptivities ranging from 0.43 x 103-7.20 x 103 l mol-1 cm-1. The proposed method has been applied successfully for the determination of xipamide in pure form and representative pharmaceutical formulations with high precession and good accuracy.

The objectives of the present work are to design, syhthesize and introduce novel urea/thiourea derivatives of 2-(piperazine-1-yl)-pyrimidine and 1-(4-Fluoro/4-Chloro phenyl)-piperazine molecules as tobacco mosaic virus (TMV) inhibitors. A series of urea/thiourea derivatives containing pyrimidine and piperazine moieties were synthesized, characterized using Fourier-transform infrared (FTIR) mass spectra, nuclear magnetic resonance (NMR) spectroscopy, elemental analysis and evaluated their sustainability using biological experiments. The anti-viral bioassay of the title compounds showed an antiviral activity against TMV. The compounds synthesized, 9j, 6g and 3d, showed highly-potential curative, protective, and inhibitory activities against TMV at 500 mg/mL formulation. All these compounds were allowed to quantum-polarized-ligand (quantum mechanical and molecular mechanical (QM/MM)) docking experiments. The compounds 9j, 6g and 3d structurally exhibited identical higher affinity towards TMV-Helicase and TMV-Coat proteins. The docking interactions proposed had two stage inhibition of TMV virus by binding to coat protein and helicase for inhibition of RNA replication. The long-range molecular dynamics (150 ns) simulations has revealed more consistency by 9j, 6g and 3d. The present study outcomes good binding propensity for active-tunnel of TMV-Hel enzyme, by these thiourea, urea derivatives, 9j, 6g and 3d, to suggest that the designed and synthesized were ideal for proposing as selective novel inhibitors to target for TMV.

A stability indicating high performance thin layer chromatography (HPTLC) method was developed and validated for determination of two anti-diabetic drugs, nateglinide and metformin hydrochloride in co-formulations. Study was performed on pre-coated silica gel HPTLC plates using chloroform:ethyl acetate:acetic acid (4:6:0.1 v/v/v) as the mobile phase. A TLC scanner set at 216nm was used for direct evaluation of the chromatograms in

A stability indicating high performance thin layer chromatography (HPTLC) method was developed and validated for determination of two anti-diabetic drugs, nateglinide and metformin hydrochloride in co-formulations. Study was performed on pre-coated silica gel HPTLC plates using chloroform:ethyl acetate:acetic acid (4:6:0.1 v/v/v) as the mobile phase. A TLC scanner set at 216nm was used for direct evaluation of the chromatograms in

A stability indicating high performance thin layer chromatography (HPTLC) method was developed and validated for determination of two anti-diabetic drugs, nateglinide and metformin hydrochloride in co-formulations. Study was performed on pre-coated silica gel HPTLC plates using chloroform:ethyl acetate:acetic acid (4:6:0.1 v/v/v) as the mobile phase. A TLC scanner set at 216nm was used for direct evaluation of the chromatograms in