Two Simple, accurate, precise, and rapid spectrophotometric and conductometric methods were developed for the estimation of erythromycin thiocyanate (I), clarithromycin (II), and azithromycin dihydrate (III) in both pure and pharmaceutical dosage forms. e spectrophotometric procedure depends on the reaction of rose bengal and copper with the cited drugs to form stable ternary complexes which are extractable with methylene chloride, and the absorbances were measured at 558, 557, and 560 nm for (I), (II), and (III), respectively. e conductometric method depends on the formation of an ion-pair complex between the studied drug and rose bengal. For the spectrophotometric method, Beer's law was obeyed. e correlation coefficient ( 2 ) for the studied drugs was found to be 0.9999. e molar absorptivity ( ), Sandell's sensitivity, limit of detection (L�D), and limit of quanti�cation (L��) were also calculated. e proposed methods were successfully applied for the determination of certain pharmaceutical dosage forms containing the studied drugs Submit your manuscripts at

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A simple, rapid and sensitive spectrophotometric method for the determination of micro amounts of cefepime hydrochloride and cefuroxime sodium is described. The method is based on reduction of 2,3,5-triphenyltetrazolium chloride (TTC) by the cited drugs in slightly alkaline medium leading to formation of a highly colored formazan derivative. Different variables affecting the color development were investigated and optimized. Absorbance measurements were made at 483 nm. Under the proposed conditions, this method is applicable over concentration range of 4–50 µg ml-1with molar absorpitivities ranging from 5.208 x 103–1.217 x 104 L.mol-1.cm-1and Sandell's sensitivities ranging from 1.007 x 10-3–2.727 x10-3µg cm-2. The proposed method was successfully applied for analysis of the cited drugs in formulations and the recovery percentages ranged from 99.47 to 99.8%. The results obtained demonstrated that the proposed method is equally accurate, precise and reproducible as the reported methods thus it is recommended for quality control and routine analysis where time, cost effectiveness and high specificity of analytical techniques are of great importance.

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

A novel potentiometric method for in-situ testing of terbinafine HCl dissolution behavior using novel liquid inner contact ionselective electrode membrane was developed. Terbinafine HCl is slightly soluble in water so, the use of ion-selective electrode for its determination is challenge. The sensor was polyvinyl chloride matrix membrane electrode in which sodium tetraphenylborate was used as cation exchanger and bis (2-ethyl hexyl) sebacate as plasticizer. The ion pair was formed by soaking membrane in drug solution. Linear response of terbinafine HCl was found in the dynamic range of 10 −6 to 10 −2 mol L −1 . Dissolution test was performed according to FDA regulations using paddle-(USP type 2). So, the proposed ion selective electrode membrane was successfully used as a benchtop in-situ monitor to study the dissolution behavior of terbinafine HCl tablets without need of sample pretreatment or complicated withdrawal steps. Also, the proposed sensor was successfully used for terbinafine HCl determination in dosage forms including spray formulation which contains alcohol percentage as solvent and urine with good recovery.