Quantitation of Acyclovir in Pharmaceutical Dosage forms using High-Performance Liquid Chromatography

Abstract

A stability-indicating high performance liquid chromatography method for the quantitation of acyclovir in pharmaceutical dosage forms (capsules, ointment and injection) has been developed. The method is accurate and precise with a percent relative standard deviation of 1.2 based on 5 readings. The excipients present in the dosage forms did not interfere with the assay method. The recovery from the synthetic mixtures was quantitative. The samples decomposed under drastic conditions showed a new peak in the chromatogram. Acyclovir appears to be more stable in the alkaline than in the acidic solution. There appears to be a distribution/decomposition problem with the ointment sample being marketed in certain types of tubes used previously and still on the market.     

Quantitation of Cephalexin in Pharmaceutical Dosage Forms Using High-Performance Liquid Chromatography

A high-performance liquid chromatography method has been developed to quantify cephalexin in pharmaceutical dosage forms, capsules, pediatric drops and suspensions. The method is accurate and precise with a percent relative standard deviation of 0.8 based on 6 readings. There is no interference from a variety of excipients present in the dosage forms. The procedure for the extraction of cephalexin from the dosage forms is very simple. The method is stability indicating since a sample decomposed using sodium hydroxide showed very little potency and new peaks in the chromatogram. In the powder form cephalexin appears to be very stable.     

Quantitation of Cephalexin in Pharmaceutical Dosage Forms Using High-Performance Liquid Chromatography

Abstract

A high-performance liquid chromatography method has been developed to quantify cephalexin in pharmaceutical dosage forms, capsules, pediatric drops and suspensions. The method is accurate and precise with a percent relative standard deviation of 0.8 based on 6 readings. There is no interference from a variety of excipients present in the dosage forms. The procedure for the extraction of cephalexin from the dosage forms is very simple. The method is stability indicating since a sample decomposed using sodium hydroxide showed very little potency and new peaks in the chromatogram. In the powder form cephalexin appears to be very stable.     

Stability-Indicating HPLC Method for Betaxolol HCl and Its Pharmaceutical Dosage Forms

Abstract

The present work describes a specific, stability-indicating high-performance liquid chromatographic method for determination of betaxolol HCl and its pharmaceutical dosage forms. Betaxolol HCl was chromatographed on a microbondapak C18 column utilizing a simple mixture of methanol: acetonitrile:0.1% diethylamine (pH 3.0 adjusted using orthophosphoric acid). It was detected at 222 nm. The method is accurate and precise with a percent relative standard deviation of 0.11 based on 6 readings. A number of inactive ingredients present in the dosage forms (eye drop, tablet, gel) did not interfere in the assay procedure. The recovery from synthetic mixtures was quantitative. The extraction procedure from the dosage forms is very simple. The drug appears to be very sensitive to acids (such as sulfuric acid) since 100% of the drug decomposed on boiling for 5 min.     

Quantitation of Cefaclor in Pharmaceutical Dosage Forms Using High Performance Liquid Chromatography

A stability-indicating high-performance liquid chromatography for the quantitation of cefaclor in pharmaceutical dosage forms has been developed. The method is accurate and precise with a percent relative standard deviation of 1.2 based on 5 readings. A number of inactive ingredients present in the capsules and suspensions did not interfere with the assay procedure. The extraction procedure from the dosage forms is very simple. The recovery from the synthetic mixtures was quantitative. The capsules which had expired 3 years ago lost only 3% of the potency. The drug appears to be very sensitive to strong acids or bases since a 5 minute boiling caused 100% degradation of drug in both the solutions.     

Quantitation of Cefaclor in Pharmaceutical Dosage Forms Using High Performance Liquid Chromatography

Abstract

A stability-indicating high-performance liquid chromatography for the quantitation of cefaclor in pharmaceutical dosage forms has been developed. The method is accurate and precise with a percent relative standard deviation of 1.2 based on 5 readings. A number of inactive ingredients present in the capsules and suspensions did not interfere with the assay procedure. The extraction procedure from the dosage forms is very simple. The recovery from the synthetic mixtures was quantitative. The capsules which had expired 3 years ago lost only 3% of the potency. The drug appears to be very sensitive to strong acids or bases since a 5 minute boiling caused 100% degradation of drug in both the solutions.     

Quantitation and Stability of Verapamil Hydrochloride using High-Performance Liquid Chromatography

A high-performance liquid chromatography method for the quantitation of verapamil hydrochloride in pharmaceutical dosage forms has been developed. The method is precise and accurate with a relative standard deviation of 0.63% based on six injections. No preliminary extraction procedure is required to assay injections and a very simple extraction procedure is needed for tablets. There is no interference from the excipients and the method appears to be stability-indicating. The optimum pH range of stability is about 3.2 to 5.6 and the phosphate buffer and ionic strength have very little effect on the stability. Verapamil hydrochloride appears to be a very stable compound since in 105 days at 50°, the aqueous solutions (0.5 mg/ml) did not decompose.     

Quantitation and Stability of Verapamil Hydrochloride using High-Performance Liquid Chromatography

Abstract

A high-performance liquid chromatography method for the quantitation of verapamil hydrochloride in pharmaceutical dosage forms has been developed. The method is precise and accurate with a relative standard deviation of 0.63% based on six injections. No preliminary extraction procedure is required to assay injections and a very simple extraction procedure is needed for tablets. There is no interference from the excipients and the method appears to be stability-indicating. The optimum pH range of stability is about 3.2 to 5.6 and the phosphate buffer and ionic strength have very little effect on the stability. Verapamil hydrochloride appears to be a very stable compound since in 105 days at 50°, the aqueous solutions (0.5 mg/ml) did not decompose.     

Thermal Methods of Analysis in Solid Dosage Technology

A survey is given on some aspects of the application of thermoanalytical methods, viz. differential thermal analysis /DTA/, differential scanning calorimetry /DSC/, thermogravimetry /TG/ and derivative TG /DTG/, in solid dosage technology. The review has been preceded by a short characterization of these methods. Further, the usefulness of the thermal methods of analysis in the purity determination, analysis of reaction kinetics of drugs and characterization of suppository and ointment bases has been discussed. The presented studies include also the qualitative and quantitative analysis of solid dosage forms and studies on tablet disintegration. Particular attention has been paid to papers dealing with the possibility of replacing of some expensive and time-consuming methods of classical analysis by rapid and fully automated methods of thermal analysis in control industrial laboratories.     

Comparative Evaluation of Four Dissolution Apparatus

Four dissolution methods, the rotating basket, the rotating paddle, the rotating basket with paddle and the stationary basket-rotating paddle, were evaluated using capsules and non-disintegrating pellets of salicylic acid. The agitation intensity produced by the rotating basket method was very low and differed significantly throughout the vessel. However, it did not differ significantly at different positions in the stationary basket-rotating paddle method. This method offered considerable advantages and hence appears to be a suitable alternative to the existing compendial methods which have limitations for evaluation of dosage forms which tend to float on the dissolution medium.     

Thermal Methods of Analysis in Solid Dosage Technology

Abstract

A survey is given on some aspects of the application of thermoanalytical methods, viz. differential thermal analysis /DTA/, differential scanning calorimetry /DSC/, thermogravimetry /TG/ and derivative TG /DTG/, in solid dosage technology. The review has been preceded by a short characterization of these methods. Further, the usefulness of the thermal methods of analysis in the purity determination, analysis of reaction kinetics of drugs and characterization of suppository and ointment bases has been discussed. The presented studies include also the qualitative and quantitative analysis of solid dosage forms and studies on tablet disintegration. Particular attention has been paid to papers dealing with the possibility of replacing of some expensive and time-consuming methods of classical analysis by rapid and fully automated methods of thermal analysis in control industrial laboratories.     

Comparative Evaluation of Four Dissolution Apparatus

Abstract

Four dissolution methods, the rotating basket, the rotating paddle, the rotating basket with paddle and the stationary basket-rotating paddle, were evaluated using capsules and non-disintegrating pellets of salicylic acid. The agitation intensity produced by the rotating basket method was very low and differed significantly throughout the vessel. However, it did not differ significantly at different positions in the stationary basket-rotating paddle method. This method offered considerable advantages and hence appears to be a suitable alternative to the existing compendial methods which have limitations for evaluation of dosage forms which tend to float on the dissolution medium.     

Quantitation of Ranitidine Hydrochloride in Tablets and Injections Using High-Performance Liquid Chromatography

Abstract

A stability-indicating reverse-phase high-performance liquid chromatography method without the use of a counterion has been developed to quantify ranitidine hydrochloride in pharmaceutical dosage forms. The method is accurate and precise with a percent relative standard deviation of 1.5 based on 5 injections. The extraction procedure for ranitidine from tablets is very simple and there was no interference from the excipients present. Ranitidine appears to be stable to heat on the acidic side and very susceptible to decomposition on the basic side. It lost 84.4% of potency on 20 minute boiling with sodium hydroxide with a new peak in the chromatogram. It lost 37.8% of the potency on treatment with hydrogen peroxide solution for 20 minutes at room temperature with 2 new peaks in the chromatogram.     

Optimization of Slow-Release Tablet Formulations Containing Montmorillonite III. Mechanism of Release

The release of sodium sulfathiazole from slow-release tablet dosage forms containing 30% colloidal aluminum silicate and 20% drug, appears to follow first-order kinetics. Analysis of the data however, suggests that several mechanisms including hydration of the clay, diffusion of drug through a hydrated gelatinous barrier and attrition of the gel layer may contribute to the dissolution of sodium sulfathiazole from the tablet matrix. The influence of tablet shape and size on the dissolution properties of drug from the dosage forms was also examined.     

Quantitation of Cefadroxil in Pharmaceutical Dosage Forms Using High-Performance Liquid Chromatography

A high-performance liquid chromatography method for the quantitation of cefadroxil has been developed. The method has been applied to quantify cefadroxil in pharmaceutical dosage forms (capsules, suspensions and tablets) of 2 different manufacturers. A simple extraction procedure to extract cefadroxil from the dosage forms has been developed. The results were excellent with percent relative standard deviation of 1.2 based on 5 readings. A variety of inactive ingredients present in the dosage forms did not interfere with the assay procedure. After formulating, the suspensions were stable for longer periods at 5^o than recommended on the label.     

A Mathematical Model for Disintegration of Solid Dosage Forms Using a Cascading Disintegration Apparatus

A modification in basket-rack assembly is proposed that enables one to develop the mathematical model for disintegration of solid dosage form. Once the parameters of the model is known, the true disintegration rate constant can be determined. The method is based on the assumption of deaggregation of solid dosage forms in a cascading system     

Quantitation of Promethazine Hydrochloride in Pharmaceutical Dosage Forms Using High Performance Liquid Chromatography

A stability-indicating HPLC assay method has been developed to quantify promethazine hydrochloride in pharmaceutical dosage forms, injection, oral liquids, suppositories and tablets. The method is accurate and precise with a percent relative standard deviation of 0.4 based on 6 readings. The recoveries from the synthetic mixtures were quantitative. Three new peaks in the chromatogram were detected from a decomposed sample. A number of active and inactive ingredients, colors, preservatives, flavors, antioxidants, phenylephrine and codeine present in the dosage forms did not interfere with the assay procedure.     

Evaluation of Oil/Water-Type Cyclosporine Gel Ointment with Commercially Available Oral Solution

Oil/water-type cyclosporine (CyA) hydrogel ointment was evaluated as a candidate for the percutaneous application of CyA. The physical properties and the permeation profiles of 2% w/w CyA gel ointment were compared with other CyA ointments. All ointments used in this study were prepared with commercially available CyA (Sandimmune) oral solution, unlike the ointment reported in the publication of by Mizoguchi et al. The gel ointment required a surfactant corresponding to 5-7% w/w to obtain fine uniform particles. Mean diameter of oily particles in the gel ointment was 8.75 μm. The permeation of CyA from the ointments was investigated by using the abdominal skin of hairless rats in vitro. The percutaneous permeation of CyA was observed to be influenced by a variety of ointment bases used and by the presence of a stratum corneum which plays a role as the main barrier. In intact skin, the extent of permeation from the gel ointment was almost equivalent to that from Mizoguchi's ointment, which used the raw CyA. No permeation was observed in ointment bases with either white petrolatum or hydrophilic petrolatum, indicating values under the limit of detection (78 ng/ml) of the high-performance liquid chromatographic method used in this study. On the other hand, in stripped skin, differences in flux value of each ointment were shown. Those values increased in the following order: Mizoguchi's ointment, white petrolatum, hydrogel, hydrophilic petrolatum. From these results, hydrogel ointment seemed to be applicable for various skin diseases which respond to CyA. Of the physical properties, spreadability and consistency showed that gel ointment was superior to Mizoguchi's ointment. In stability tests, the gel ointment was stable with regard to particle size and residual CyA for 4 weeks. These results suggested that the oil/water-type CyA hydrogel ointment prepared in a combination with hydrogel and commercially available oral solution was useful for practical hospital preparations, with good physical properties, permeability, and stability.     

In vitro release and diffusion studies of promethazine hydrochloride from polymeric dermatological bases using cellulose membrane and hairless mouse skin

The study was designed to investigate the feasibility of developing a transdermal drug dosage form of promethazine hydrochloride (PMH). The in vitro release and diffusion characteristics of PMH from various dermatological polymeric bases were studied using cellulose membrane and hairless mouse skin as the diffusion barriers. These included polyethylene glycol (PEG), hydroxypropyl methylcellulose (HPMC), cross-linked microcrystalline cellulose, and carboxyl methyl cellulose sodium (Avicel CL-611), and a modified hydrophilic ointment USP. In addition, the effects of several additive ingredients known to enhance the drug release from topical formulations were evaluated. The general rank order for the drug release from these formulations using cellulose membrane was observed to be PEG > HMPC > Avicel CL-611 > hydrophilic ointment base. The inclusion of the additives had little or no effect on the drug diffusion from these bases, except for the hydrophilic ointment formulation containing 15% ethanol, which provided a significant increase in the drug release. However, when these formulations were studied for drug diffusion through the hairless mouse skin, the Avicel CL-611 base containing 15% ethanol exhibited the optimum drug release. The data also revealed that this formulation gave the highest steady-state flux, diffusion, and permeability coefficient values and correlated well with the amount of drug release.     

In Vitro Release and Diffusion Studies of Promethazine Hydrochloride from Polymeric Dermatological Bases Using Cellulose Membrane and Hairless Mouse Skin

The study was designed to investigate the feasibility of developing a transdermal drug dosage form of promethazine hydrochloride (PMH). The in vitro release and diffusion characteristics of PMH from various dermatological polymeric bases were studied using cellulose membrane and hairless mouse skin as the diffusion barriers. These included polyethylene glycol (PEG), hydroxypropyl methylcellulose (HPMC), cross-linked microcrystalline cellulose, and carboxyl methyl cellulose sodium (Avicel® CL-611), and a modified hydrophilic ointment USP. In addition, the effects of several additive ingredients known to enhance the drug release from topical formulations were evaluated. The general rank order for the drug release from these formulations using cellulose membrane was observed to be PEG > HMPC > Avicel CL-611 > hydrophilic ointment base. The inclusion of the additives had little or no effect on the drug diffusion from these bases, except for the hydrophilic ointment formulation containing 15% ethanol, which provided a significant increase in the drug release. However, when these formulations were studied for drug diffusion through the hairless mouse skin, the Avicel CL-611 base containing 15% ethanol exhibited the optimum drug release. The data also revealed that this formulation gave the highest steady-state flux, diffusion, and permeability coefficient values and correlated well with the amount of drug release.