T.K. Ravi

Cefixime, cefpodoxime and cefepime are cephalosphrin antibiotics used widely in the different infectious diseases. Newer HPTLC methods were developed for their estimation from individual dosage forms due to versatile applications and advantages. The HPTLC chromatogram of cefixime was developed by using a mobile phase ethylene acetate: methanol: water (4.5:5:0.5%v/v) and scanning wavelength was 292nm. The Rf value was 0.58±0.02. The mobile phase optimized for cepodoxime was methanol: ethyl acetate: toluene (1.5:3:5.5% v/v), with the Rf value 0.53±0.02. The cefixime was retained using methanol :water : chloroform (6:3:1%v/v), on a  silica gel G60 F254 aluminium sheet and  scanning wavelength kept at 285nm. The Rf value was 0.44. The methods were optimized validated as per guidelines and successfully applied for individual dosage form containing  of each of cephalosporin.

Euphorbia Hirta belonging to the Euphorbiaceae family contains more amounts of phenolic compounds and flavonoids which are responsible for the main pharmacological actions like anti-oxidant, anti-inflammatory, anti-dengue and anti-cancer. Considering the current importance of these ingredients, an attempt has been made for the simultaneous estimation of gallic acid, rutin and quercetin from euphorbia hirta by successive extraction involves the use of solvents in an order of increasing polarity in soxhlet extractor at 30-45 °C using 800 ml solvents for 5 hours in increasing polarity to isolate the active constituents without other interferences. Hence we proposed to develop easy, rapid, accurate, precise and reliable analytical HPTLC method for the standardization of Euphorbia hirta(L) using gallic acid, rutin and quercetin as phytochemical markers from its methanolic extract and herbal capsule formulation. The separation was performed on TLC aluminum Plates precoated with silica gel 60F254, good separation was achieved in the mobile phase of butyl acetate: 1,4-dioxane (5:5% v/v) and densitometric determination of gallic acid, rutin and quercetin was carried out at 266nm.The linear regression data showed a good linearity in the concentration range of 136-748ng/spot of gallic acid, rutin and quercetin with a good correlation coefficient of 0.9989. Limit of detection was found to be 102 ng/spot of gallic acid,17ng/spot of rutin and 68ng/spot of quercetin. The limit of quantification for the estimation of gallic acid, rutin and quercetin was found to be 136ng/spot.

Two simple, sensitive and precise HPTLC and RP-HPLC methods were developed for the estimation of berberine from Coscinium fenestratum, and its formulation. For the determination of berberine by HPTLC method, precoated silicagel 60F254 on aluminium sheets and a mobile phase system comprising of n-butanol: glacial acetic acid : water (8:1:1 % v/v/v ) was selected. After development the plate was scanned and quantified at 350 nm. Linearity was found in the concentration range of 10 to 50 ng/spot (r=0.9992). Limit of detection was found to be 5 ng/spot and limit of quantification was found to be 10 ng/spot. In RP-HPLC method, separation was achieved on a Phenomenex, Luna, C18 column (150 x 4.6mm internal diameter, 5µ particle size) using a mobile phase consisting of potassium dihydrogen phosphate (pH - 2.5) (A)  : acetonitrile (B), where B was run in gradient programme (20% for 0.01-20min, 50% for 20-25min, 50% for 25-26min, 20% for 26-30min), at a flow rate of 1ml/min and the elute was monitored at 220nm. The calibration curve was obtained in the range of 100 - 500 µg/mL. The slope, intercept and correlation coefficient values were found to be 57588, 6041and 0.9959, respectively. The method was validated in compliance with ICH guidelines. Low relative standard deviation and good % recovery values of both the methods showed that the developed methods were highly precise, accurate and can be employed for the routine analysis of formulations containing berberine.

A simple validated high performance thin layer chromatographic method was developed for the determination of Aceclofenac in presence of its degradant. Separation of Aceclofenac from the degradant could be achieved using aluminium backed silica gel 60 F254 plate with toluene: ethyl acetate: glacial acetic acid, (6:4:0.02v/v) as mobile phase. Densitometry analysis was carried out at 282 nm. The method showed high sensitivity with good linearity over the concentration range of 0.5 – 4 µg/spot. The method was successfully applied to the analysis of pharmaceutical formulation containing Aceclofenac with excellent recovery. The LOD and LOQ were found to be 0.1 and 0.5 µg/spot. Aceclofenac was subjected to hydrolytic, oxidative, thermal and photolytic degradation. It was found that the drug was highly susceptible to acid hydrolysis. Kinetic investigation of the drug followed pseudo-first order reaction. From the Arrhenius plot the activation energy was found to be 13.19 kcal/mole. Statistical analysis revealed that the developed method is accurate and reliable. Hence it can be used for routine quality control analysis of Aceclofenac in tablet formulation.