ABSTRACT
A simple, rapid, precise, accurate, sensitive and stability indicating high performance liquid chromatographic method has been developed for simultaneous determination of losartan potassium and hydrochlorothiazide in pharmaceutical formulations. Method development and optimization was carried out using Design of Experiments' [DoE]. Optimized mobile phase [v/v/v] was water [containing 0.25 ml/L triethylamine], methanol and acetonitrile [60:38:30, pH adjusted to 2.7+/-0.1]. Chromatographic separation was achieved on Hypersil[registered sign]-Gold C18 [150 x 4.6 mm, 5 micro m, Thermo Fisher Scientific, USA], column at 25 +/- 2[degree sign] C. The mobile phase flow rate was 1.0 m/min. The analysis was carried out at 271 nm using 10 micro l samples. The method was validated as per the International Conference on Harmonization [ICH] guidelines. This method had a chromatographic run time of 10.0 min and a linear calibration curves ranged from 2.0 to 48.0 micro g/mL for losartan potassium, and 0.512.0 micro g/mL for hydrochlorothiazide. The limits of detection for hydrochlorothiazide and losartan potassium were 0.013 and 0.138 micro g/ml while the limits of quantitations were 0.039 and 0.418 micro g/ml, respectively. Stability studies indicate that the degradation of drugs was higher during oxidative stress than other stress. No photolytic degradation was observed
ABSTRACT
The present study reports the chemical composition, antioxidant, antibacterial, antidiarrheal as well as the spasmolytic activity of Zanthoxylum rhetsa [DC] essential oil, fractionated oil and its principal constituent [Terpinen-4-ol]. The constituents of essential oil were characterized by GC-FID and GC-MS. The pharmacological and biological activities of oil, its fraction and principal constituent were carried out in-vivo and in-vitro. The oil was rich in a group of monoterpene family, constituted mainly of terpinen-4-ol [25.43%], sabinene [16.50%], beta-pinene [10.4%], alpha-Terpineol [7.63%], gamma-Terpinene [5.64%], alpha-pinene [4.33%], and linalool [3.25%]. The antioxidant capacities of the oil, fractions and terpinen-4-ol were assessed by using spectrophotometry to measure free radical scavenger 2,2-diphenyl-1-picrylhydrazyl [DPPH]. Furthermore, the oil, its fractions and terpinen-4-ol exhibited appreciable antioxidant, antibacterial, antidiarrheal and non-selective spasmolytic activity. The study suggests that the oil and its main active constituent [terpinen-4-ol] of the studied plant would have high potential in the treatment of stress and gastrointestinal diseases
ABSTRACT
The rheological properties of oily vehicles based on patents of non-aqueous vehicles for pharmaceutical suspensions were studied. The effects of different concentrations of suspending agents and different excipients on the flow curves were also investigated. A Rotovisko viscometer [Haake] fitted with concentric cylinder sensors, NV measuring head- 500 and a temperature controlled water jacket at 37°C was used. The results showed that Fractionated Coconut Oil [FCO] alone and with 0.7% w/v lecithin exhibited Newtonian behavior. Dispersions of aluminium stearate, hydrogenated castor oil, Cab-o-sil and sucrose in FCO exhibited pseudoplastic behavior. Aluminium stearate 1% w/v and above and the oily vehicle containing aluminium stearate, hydrogenated castor oil, lecithin and sucrose exhibited thixotropic pseudoplastic properties. The omission of lecithin from the later vehicle resulted in a decrease in the apparent viscosity and the loss of thixotropy. The thixotropic pseudoplastic behavior of oily vehicles is a desirable property in liquid pharmaceutical systems that ideally should have a high consistency in the container, yet pour or spread easily after they had been stirred vigorously. Possible reasoning and suggestions were discussed
ABSTRACT
A simple, sensitive, and inexpensive high performance liquid chromatographic method has been developed for simultaneous determination of ofloxacin and ornidazole in pharmaceutical formulations. Chromatographic separation was achieved on a BDS-C[18]-Hypersil column [250 mm x 4.6 mm i.d., 10 microm]. Mobile phase was 80% water [containing 0.55 ml/L of triethylamine as peak modifier] and 20% acetonitrile; final pH was adjusted to 3.0 with orthophosphoric acid. Detection was done at 284 nm. Response was a linear function of concentration in the range 1-20 micro g/ml for ofloxacin and 2.5-50 microg/ml for ornidazole; the correlation coefficients were 0.9998 and 0.9995, respectively. The limit of detection were 0.01 and 0.02 microg/ml for ofloxacin and ornidazole respectively, where as limit of quantitation were 0.05 and 0.1 micro g/ml. The accuracy result for ofloxacin and ornidazole at eighty percent drug [80%], hundred percent [100%], and one hundred and twenty percent [120%] were ranged from 99.6-100.9%. The inter- and intra-day precision was less than 1%. Total elution time for the two components was less than 9 min
Subject(s)
Ofloxacin/chemistry , Ornidazole/chemistry , Spectrophotometry, Ultraviolet , Validation Studies as Topic , Chemistry, Pharmaceutical , Indicators and ReagentsABSTRACT
A simple, sensitive and precise HPLC method for the quantitation of alfuzosin in human plasma has been developed and validated. Commercially available atenolol was used as an internal standard. After liquid-liquid extraction, alfuzosin and atenolol [I.S.] in human plasma were analyzed using mobile phase containing25% v/v acetonitrile and 75% v/v water [containing Iml/L triethylamine as peak modifier, pH adjusted to 2.5 with orthophosphoric acid]. Chromatographic separation was achieved on a BDS Hypersil-C18 column [50mm x 4.6 mm i.d., particle size 5 micro m] using isocratic elution at [flow rate 0.5 mL/min.] The peak was detected using a fluorescence detector programmed for 0.2 min at Ex 222 mm and Em 300 nm for atenolol and 2-4 min at Ex 265 nm and Em 380 nm for alfuzosin, and the total time for a chromatographic separation was 4 min. The validated quantitation ranges of this method were 0.1-25 ng/ml with coefficients of variation between 1.6 - 4.8%. Mean recoveries were 98.0 +/- 0.9%. The within and between batch precision was 2.74 - 3.28% and 2.65 - 2.77%, respectively. The within and between batch relative error [bias] were -7.1 - [-0.3]% and -1.60 - 2.46%, respectively. Stability of alfuzosin in plasma was >/= 94.9%, with no evidence of degradation during sample processing and 30 days storage in a deep freezer at -70 +/- 5°C. The absolutes extraction recoveries of drug from plasma was >/= 98%. This validated method is sensitive and simple with between-batch precision of