Simultaneous determination of methylparaben, propylparaben, hydrocortisone acetate and its degradation products in a topical cream by RP-HPLC

Mathematical filtration of quaternary mixture to the zero order spectra of its individual components

Simple accurate and precise validated UV spectrophotometric methods have been described here for the simultaneous determination of Tretinoin (TN) Eusolex (EX) Hydroquinone (HQ) & Hydrocortisone acetate (HC) in their dosage form. Simultaneous determination of these four drugs was a major challenge till now. Each spectrum was filtered alone to its zero-order absorption spectrum (D⁰) form getting spectra typical to each pure component separately. Four methods were applied depending upon constants obtained from extended regions of partially overlapped spectra in the zero or first derivative forms. The methods applied are constant multiplication coupled with spectrum subtraction method (CM-SS) derivative transformation coupled with spectrum subtraction method (DT-SS) constant value method (CV) and concentration value (conc.value) method. The partially overlapped spectra of TN and EX in the mixture were obtained by CM-SS in their zero-order form allowing direct measurement at their λ_max while the resolved binary mixture of HQ and HC obtained by SS; was determined by derivatization and transformed to their zero order by DT-SS. Also Ex and HQ concentrations were determined by the graphical representation of data only without regression equation by concentration value method and the results were compared to the conventional constant value method using a regression equation. The methods applied to the quaternary mixture under study were successfully applied for the simultaneous determination of the four drugs in synthetic mixtures and in their combined dosage form Tritospot® cream. Comparing the acquired results statistically together and to official methods demonstrated no significant difference.

Formulation, optimization, qualitative and quantitative analysis of new dosage form of corticosteroid

Background

The objective of the present research work is to develop the entirely new drug product formulation (Ophthalmic Suspension) which belongs to the therapeutic class of steroids drugs (Corticosteroid). There are different dosage forms of Triamcinolone acetonide to treat different systemic as well as topical diseases as per patient symptomatic conditions. Due to non-availability of this active drug (Triamcinolone acetonide) ophthalmic dosage form in the national and international market research work is carried out to enter in this dosage form.

Results

In the formulation design and development, different inactive like polysorbate 30 mg/mL, PEG-12 glyceryl dimyristate 70 mg/mL, ethyl alcohol 10 µL/mL, citric acid 1 mg/mL, sodium citrate 3.5–4.0 mg/mL, BKC 0.15 mg/mL and water for injection have been used at different stages in different proportions during the manufacturing procedure. Gradient HPLC, C18 column, 5 µm, 100 A, 3.9 mm × 300 mm, detector UV/Vis @ 254 nm, column oven, auto-sampler, degasser, is used and this analytical testing method is validated to obtain the accurate results. The excipients play different roles including solvent, antioxidant, solubilizer, emulsifier, antibacterial, preservative, anticoagulant, antimicrobial agent, surfactant and buffers in the stability of active drug for its excellent therapeutic output results. Correlation coefficient factor is greater than 0.999 which indicates that the method has good linearity at proposed concentration against triamcinolone acetonide.

Conclusions

Excellent physical and chemical properties like physical appearance, pH, specific gravity, viscosity, re-suspendability, sedimentation volume is accomplished to meet the requirements of the eye treatment products. On the basis of experimental results achieved during validation process, it can be assumed that the current analysis method is more accurate, precise, specific, linear and consistency indicating in the range of 70 to 130% of the analyte concentration. From the physical, chemical behaviors and chemical assay of the newly developed drug formulation of corticosteroid (triamcinolone acetonide) it is concluded that it can be probably put for further clinical trial in different phases for human use.

A simple and rapid HPLC method for determination of parabens and their degradation products in pharmaceutical dosage forms

A stability-indicating HPLC method was developed for the simultaneous determination of paraben mixture and its degradation products in effervescent potassium chloride tablets. The chromatographic separation was achieved on a Waters Cortecs C18 column (2.7 μm, 4.6 × 150 mm) using gradient elution. The optimized mobile phase consisted of 0.1% orthophosphoric acid in purified water as solvent A and purified water, acetonitrile, and orthophosphoric acid (100:900:1, v/v) as solvent B. The flow rate was 0.8 mL/min, and column temperature was maintained at 35°C. The injection volume was 10 μL, and UV detection was carried out at 254 nm. The selectively developed method has optimal separation among p-hydroxybenzoic acid, methylparaben, ethylparaben, propylparaben, and butylparaben peaks in the presence of specified and unspecified degradation products in the determination of drug product. The mass balance obtained from forced degradation studies was ≥95% and thus proves the stability-indicating property of the developed method. The developed reversed-phase HPLC method has been validated according to the International Conference on Harmonization guidelines. The correlation coefficients for all the peaks were >0.9999. The results of the other validation parameters were found within the limits. Finally, the optimized method was used in the quality control lab for stability analysis.

A Critical Review of Analytical Methods in Pharmaceutical Matrices for Determination of Corticosteroids

Corticosteroids are a class of hormones released by the adrenal cortex, which includes glucocorticoids and mineralocorticoids. Glucocorticoids have an important role in the metabolism of carbohydrates, proteins and calcium and effective anti-inflammatory and immunosuppressive activity. Due to their intense immunomodulatory and anti-inflammatory activity, glucocorticoids are used in the treatment of various inflammatory, malignant, allergic conditions such as rhinitis, asthma, dermatological, rheumatic, ophthalmic and neurological diseases, as well as after organ transplants. They are the most widely prescribed drugs in the world. The objective of this review is to provide an overview of the analytical methods in pharmaceutical matrices for determination of corticosteroids. In this study, the predominance of liquid chromatography methods for the analysis of corticosteroids from pharmaceutical products is evident for both liquid and semisolid dosage forms as well as for solids. The same can be said for topical, oral and parenteral formulations. Methods such as spectrophotometry are also used, but given the advantages of chromatographic methods such as better selectivity and sensitivity, they have become the choice for analysis of these drugs, however, most methods still do not meet the credentials of "green chemistry."

Comparative study of two different chromatographic approaches for quantitation of hydrocortisone acetate and pramoxine hydrochloride in presence of their impurities

In the present study, we compare the performance of two reversed-phase liquid chromatographic approaches using different eluents either conventional hydro-organic eluent or micellar one for simultaneous estimation of hydrocortisone acetate and pramoxine hydrochloride in presence of their degradants and process-related impurities; hydrocor-tisone and 4-butoxyphenol, respectively. For conventional reversed-phase liquid chromatography (RPLC), separation of the studied compounds was completed on an Inertsil ODS 3-C18 column (150 mm × 4.6 mm, 5 μm particle size) with a mobile phase consists of 50 mM phosphate buffer (pH 5.0): acetonitrile (50: 50, v/v). For micellar liquid chromatography (MLC), an Eclipse XDB-C8 column (150 mm × 4.6 mm, 5 μm particle size) was chosen for the separation with a green mobile phase consists of 0.15 M sodium dodecyl sulfate, 0.3% triethylamine and 10% n-butanol in 20 mM orthophosphoric acid (pH 5.0). Both methods were extended to analyze hydrocortisone acetate and pramoxine hydrochloride in their co-formulated cream. RPLC was superior to MLC with regard to sensitivity for the estimation of impurities. While, MLC represents an eco-friendly, less hazardous and biodegradable approach. Furthermore, the direct injection of the cream to the system without the need to laborious samples pretreatment, excessive amount of analysis time and/or use of large amount of toxic organic solvents is one of the outstanding advantages of MLC.

Formulation of Carbopol®/Poly(2-ethyl-2-oxazoline)s Mucoadhesive Tablets for Buccal Delivery of Hydrocortisone

Poly(2-ethyl-2-oxazoline) has become an excellent alternative to the use of poly(ethylene glycol) in pharmaceutical formulations due to its valuable physicochemical and biological properties. This work presents a formulation of poorly-water soluble drug, hydrocortisone, using interpolymer complexes and physical blends of poly(2-ethyl-2-oxazoline)s and two Carbopols^® (Carbopol 974 and Carbopol 971) for oromucosal administration. The swelling, hydrocortisone release and mucoadhesive properties of a series of tablet formulations obtained by combination of different Carbopols with poly(2-ethyl-2-oxazoline)s of different molecular weights have been evaluated in vitro.

Novel HPLC Analysis of Hydrocortisone in Conventional and Controlled-Release Pharmaceutical Preparations

An isocratic sensitive and precise reverse phase high-performance liquid chromatography (RP-HPLC) method was developed and validated for the determination and quantification of hydrocortisone in controlled-release and conventional (tablets and injections) pharmaceutical preparations. Chromatographic separation was achieved on an ODS (C18), 5 μm, 4.6 × 150 mm, with an isocratic elution using a freshly prepared mobile phase of composition methanol : water : acetic acid (60 : 30 : 10, v/v/v) at a flow rate of 1.0 ml/min. The detection of the drug was successfully achieved at a wavelength of 254 nm. The retention time obtained for the drug was 2.26 min. The proposed method produced linear detectable responses in the concentration range of 0.02 to 0.4 mg/ml of hydrocortisone. High recoveries of 98–101% were attained at concentration levels of 80%, 100%, and 120%. The intraday and interday precision (RSD) were 0.19–0.55% and 0.33–0.71%, respectively. A comparison of hydrocortisone analyses data from the developed method and the official USP method showed no significant difference (p > 0.05) at a 95% confidence interval. The method was successfully applied to the determination and quantification of hydrocortisone in six controlled-release and fifteen conventional release pharmaceutical preparations.

Methylparaben removal using heterogeneous photocatalysis: effect of operational parameters and mineralization/biodegradability studies

Methylparaben (MePB) is an organic compound employed mainly in the manufacture of different personal care products. However, it has been recently listed as a potential endocrine disrupter chemical. Therefore, the main objective of this work was to evaluate the degradation of MePB in aqueous solutions using heterogeneous photocatalysis with TiO₂ and hydrogen peroxide. In this way, effects of pH and the initial concentrations of catalyst, H₂O₂, and pollutant on treatment were analyzed. A face centered, central composite design was used for determination of the influence of each parameter in the process and the conditions under which the pollutant suffers the highest rates of degradation were selected. In general, results indicate that combination TiO₂/H₂O₂/light irradiation leads to ∼90 % of substrate removal after 30 min of reaction and that hydroxyl free radicals are the main specie responsible for organic matter elimination. Finally, in terms of mineralization and biodegradability, experimental results indicated that part of the organic matter was transformed into CO₂ and water and the photo-treatment promoted an increase in samples biodegradability.

Novel two wavelength spectrophotometric methods for simultaneous determination of binary mixtures with severely overlapping spectra

This work presents the application of different spectrophotometric techniques based on two wavelengths for the determination of severely overlapped spectral components in a binary mixture without prior separation. Four novel spectrophotometric methods were developed namely: induced dual wavelength method (IDW), dual wavelength resolution technique (DWRT), advanced amplitude modulation method (AAM) and induced amplitude modulation method (IAM). The results of the novel methods were compared to that of three well-established methods which were: dual wavelength method (DW), Vierordt's method (VD) and bivariate method (BV). The developed methods were applied for the analysis of the binary mixture of hydrocortisone acetate (HCA) and fusidic acid (FSA) formulated as topical cream accompanied by the determination of methyl paraben and propyl paraben present as preservatives. The specificity of the novel methods was investigated by analyzing laboratory prepared mixtures and the combined dosage form. The methods were validated as per ICH guidelines where accuracy, repeatability, inter-day precision and robustness were found to be within the acceptable limits. The results obtained from the proposed methods were statistically compared with official ones where no significant difference was observed. No difference was observed between the obtained results when compared to the reported HPLC method, which proved that the developed methods could be alternative to HPLC techniques in quality control laboratories.

A New Validated HPLC Method for the Simultaneous Determination of 2-phenoxyethanol, Methylparaben, Ethylparaben and Propylparaben in a Pharmaceutical Gel

A novel reversed-phase HPLC method has been developed and validated for the simultaneous determination of 2-phenoxyethanol, methylparaben, ethylparaben and propylparaben preservatives. The method uses a Lichrosorb C8 (150×4.6 mm, 5 µm) column and isocratic elution. The mobile phase consisted of a mixture of acetonitrile, tetrahydrofuran and water (21:13:66, v/v/v), pumped at a flow rate of 1 ml/min. The UV detection was set at 258 nm. The method was validated with respect to accuracy, precision (repeatability and intermediate precision), specificity, linearity and range. All the parameters examined met the current recommendations for bioanalytical method validation. The developed method was successfully applied to the determination of commercially available pharmaceutical gel products for these preservatives. The procedure describes here is simple, selective and reliable for routine quality control analysis and stability tests.

A Rapid, Stability Indicating RP-UPLC Method for Simultaneous Determination of Ambroxol Hydrochloride, Cetirizine Hydrochloride and Antimicrobial Preservatives in Liquid Pharmaceutical Formulation

A stability indicating reversed phase ultra performance liquid chromatography (RP-UPLC) method was developed for simultaneous determination of ambroxol hydrochloride (AMB), cetirizine hydrochloride (CTZ), methylparaben (MP) and propylparaben (PP) in liquid pharmaceutical formulation. The desired chromatographic separation was achieved on an Agilent Eclipse plus C18, 1.8 μm (50 × 2.1 mm) column using gradient elution at 237 nm detector wavelength. The optimized mobile phase consists of a mixture of 0.01 M phosphate buffer and 0.1 % triethylamine as a solvent-A and acetonitrile as a solvent-B. The developed method separates AMB, CTZ, MP and PP in presence of twelve known impurities/degradation products and one unknown degradation product within 3.5 min. Stability indicating capability was established by forced degradation experiments and seperation of known and unknown degradation products. The lower limit of quantification was established for AMB, CTZ, MP and PP. The developed RP-UPLC method was validated according to the International Conference on Harmonization (ICH) guidelines. This validated method is applied for simultaneous estimation of AMB, CTZ, MP and PP in commercially available syrup samples. Further, the method can be extended for estimation of AMB, CTZ, MP, PP and levo-cetirizine (LCTZ) in various commercially available dosage forms.

Stationary cuvette: a new approach to obtaining analytical curves by UV-VIS spectrophotometry

BACKGROUND

Investigations in the field of pharmaceutical analysis and quality control of medicines require analytical procedures that achieve suitable performance. An analytical curve is one of the most important steps in the chemical analysis presenting a direct relationship to features such as linearity.

OBJECTIVE

This study has the aim of developing a new methodology, the stationary cuvette, to derive analytical curves by spectroscopy for drug analysis.

METHODOLOGY

The method consists basically of the use of a cuvette with a path length of 10 cm, containing a constant volume of solvent in which increasing amounts of a stock solution of the sample are added, droplet by droplet. After each addition, the cuvette is stirred and the absorbance is measured. This procedure was compared with the currently used methodology, which requires a labour-intensive dilution process, and possible sources of variation between them were evaluated.

RESULTS

The results demonstrated that the proposed technique presented high sensitivity and similar reproducibility compared with the conventional methodology. In addition, a number of advantages were observed, such as user-friendliness, cost-effectiveness, accuracy, precision and robustness.

CONCLUSION

The stationary cuvette approach may be considered to be an appropriate alternative to derive analytical curves for analysing drug content in raw materials and medicines through UV-VIS spectrophotometry.

Control of transdermal permeation of hydrocortisone acetate from hydrophilic and lipophilic formulations

The purpose of this research was the preparation of four formulations containing hydrocortisone acetate (HCA) for topical application, including two aqueous systems (hydrophilic microemulsion and aqueous gel) and two systems with dominant hydrophobicity (hydrophobic microemulsion and ointment). The formulations were tested for the release and permeation of HCA across an animal membrane. The release of HCA was found comparable for the four systems. The two microemulsions promote permeation across an ex-vivo membrane, examined by means of a Franz cell. Hydrophobic microemulsion guarantees the highest solubility (2,370 microg/ml) and flux (133 microg/cm(2).h) of the drug, since it contains almost 40% Transcutol, a permeation enhancer. Gel and ointment provide lower solubility and flux, being the values, related to the ointment, the lowest ones (562 microg/ml and 0.4 microg/cm(2).h). Experimental results allow the conclusion that gel and ointment can be suitable when it is desirable to minimize absorption of topically applied HCA as to keep the drug restricted to the diseased area and prevent side effects of the systemic presence of HCA.

Dose-response of the cultured bovine lens to butyl, methyl and propyl parabens

Pre-screening of cosmetic ingredients is vital for consumer safety. Previous in vivo techniques, such as the Draize test, have proved to be unreliable in predicting ocular irritancy and therefore there is a need for alternate testing methodologies. One such test is the scanning laser in vitro assay system which quantifies irritancy based on the focusing ability of the cultured bovine lens. In combination with confocal microscopy, a more thorough documentation of ocular irritancy can be achieved. This study investigates the response of cultured bovine lenses over time to butyl, methyl and propyl parabens, which are common antimicrobial agents found in cosmetic and ophthalmic products. The focusing ability of the lens was measured with an automated laser scanner over a period of 96 h. At 120 h post-treatment, the lenses were analysed by using a confocal laser scanning microscope to determine the characteristics of nuclei, and the morphology and distribution of mitochondria within the lenses. Irritancy to the three parabens was investigated at both an optical and cellular level. Each of the parabens was tested at 0.002% and 0.2%, where the 0.2% butyl paraben was found to be the most irritating.

Counterfeit homeopathic medicinal products: syrups. A simple and rapid LC-ESI-MS method to detect preservatives not declared in label

A rapid and simple LC-ESI-MS method for the simultaneous detection and quantitation of six preservatives in homeopathic syrups has been developed. Counterfeit homeopathic syrups are suspected to contain preservatives that are not declared in label. For this reason a method to ascertain the absence of sorbic and benzoic acids, methyl-, ethyl-, propyl- and butyl-parabens, as the most frequently utilised preservatives, has been developed. Analytes were eluted with a linear gradient of acetonitrile-5mM ammonium acetate in 12 min using 2,4-dichlorobenzylalchol as Internal Standard. The HPLC separation was performed on an Eclipse XDB-C18 (2.1 mm x 50 mm-5 microm) column and the ESI-MS detection was performed in negative ion mode. Linearity of the method was studied in the range of 2 pg to 10 ng injected and correlation coefficients r2 > or =0.9992 were obtained. LOD ranged from 0.04 to 0.4 ng mL(-1).

Stability indicating simultaneous determination of domperidone (DP), methylparaben (MP) and propylparaben by high performance liquid chromatography (HPLC)

A simple, specific and precise high performance liquid chromatographic method has been developed and validated for the simultaneous determination of methylparaben (MP), propylparaben (PP), and domperidone (DP) in oral suspension. Isocratic mobile phase consists of 0.5% w/v aqueous ammonium acetate buffer:methanol, 40:60 (v/v). Column containing octylsilyl chemically bonded to porous silica particles (Optimapak, OP C8, 150 mmx4.6 mm, 5 microm, stainless steel analytical column from RS tech) is used as stationary phase. The detection is carried out using variable wavelength UV-vis detector set at 280 nm. The solutions are chromatographed at constant flow rate of 1.0 mL/min. The method separates MP, PP, DP and droperidol (DR) impurity in less than 12 min with good resolution, peak shapes and minimal tailing. Retention times (RT) for MP, PP, DP and DR are about 3.4, 7.0, 9.0 and 10.9 min, respectively. Linearity range and percent recoveries for MP, PP and DP are 90-270, 10-30, 50-1500 microg/mL and 100.30%, 100.78% and 100.48%, respectively. Method was validated according to ICH guidelines and proved to be suitable for stability testing, homogeneity testing and quality control of these compounds in pharmaceutical preparations.

Development of an HPLC method for the analysis of Apomine in a topical cream formulation

A stability indicating, reversed-phase high performance liquid chromatographic method was developed for the quantification of Apomine, tetraisopropyl 2-(3,5-di-tert-butyl-4-hydroxyphenyl)-ethyl-1, 1-bisphosphonate, in a topical cream formulation. Analysis of Apomine in the cream formulation was performed through a dilution of the cream base with tetrahydrofuran. This allowed the current method to bypass extraction and/or centrifugation for direct injection and analysis. Separation was achieved using an Alltima C18 5 microm, 150 mm x 2.1 mm column and employed a gradient procedure, beginning with acetonitrile-water (65:35, v/v), at 0.6 mL/min for 9 min, followed by a rinse with isopropyl alcohol for 9 min. The complete gradient method has been optimized to separate Apomine from the nonpolar cream components, wash and equilibrate the column in a 30-min assay. This report demonstrates that this method is effective for quantification of Apomine in a cream formulation.

A novel gradient HPLC method for simultaneous determination of ranitidine, methylparaben and propylparaben in oral liquid pharmaceutical formulation

A selective and accurate high-performance liquid chromatographic method has been developed and validated for the simultaneous determination of ranitidine, methylparaben (MP) and propylparaben (PP) in oral liquids. Samples were purified by solid-phase extraction (SPE) using a copolymeric [poly(divinylbenzene-co-N-vinylpyrrolidone)] sorbent. The chromatographic separation was achieved by HPLC using a mixture of ammonium acetate solution (0.5 M), acetonitrile and methanol as the mobile phase with gradient elution, a Nucleosil C18 column and UV detection at 254 nm. The method was validated with respect to linearity, precision, accuracy, selectivity, and robustness. All the parameters examined met the current recommendations for bioanalytical method validation. The method was found to be applicable to routine analysis (assays and stability tests) of active compound (ranitidine) and preservatives (MP and PP).

Application of a capillary electrophoresis method for simultaneous determination of preservatives in pharmaceutical formulations

Preservatives are used to protect pharmaceutical formulations from microbial attack during the period of administration to the patient. Because of their biological activity, preservatives have to be identified and assayed according to the same rules as apply to active components. A number of methods for separation of preservatives are reported, to account for the heterogeneity of their chemical structures. A capillary electrophoretic method was devised for simple and simultaneous qualification and quantification of the preservatives most often included in pharmaceuticals, such as benzyl alcohol, parabens, phenol, m-cresol, chlorobutanol, thimerosal. After systematic method development, the electrophoretic conditions were defined as: 50 mM borate buffer pH 9.0 containing 20 mM SDS. Separations were performed at a temperature of 20 degrees C and with detection at 214 nm. Preservatives under examination can be analyzed within a 10 min run. The method was successfully validated and applied to the determination of preservatives in a number of pharmaceuticals. Results from the CE method were compared with those from reference methods.

Recent Advances in the Analysis of Steroid Hormones and Related Drugs

The development during the last 15 years and the state-of-the-art in the analysis of bulk steroid hormone drugs and hormone-like structures and pharmaceutical formulations made thereof are summarized. Other steroids (sterols, bile acids, cardiac glycosides, vitamins D) as well as biological-clinical aspects and pharmacokinetic and metabolic studies are excluded from this review. The state-of-the-art is summarized based on comparisons of monographs in the latest editions of the European Pharmacopoeia, United States Pharmacopoeia and the Japanese Pharmacopoeia. This is followed by sections dealing with new developments in the methodology for the fields of spectroscopic and spectrophotometric, chromatographic, electrophoretic and hyphenated techniques as well electroanalytical methods. The review is terminated by two problem-oriented sections: examples on impurity and degradation profiling as well as enantiomeric analysis.