Development and validation of RP-HPLC method for quantification of trace levels of topical corticosteroids in ambiphilic cream

Corticosteroids are anti-inflammatory and immunosuppressant drugs. Topical corticosteroids formulations (ointments, creams, gels) are used in the treatment of different types of dermatitis and urticaria. Considering their therapeutic and whitening effects, they are frequently used for counterfeiting of cosmetic products. Corticosteroids can cause different local and systemic side effects. HPLC method is often chosen for their analysis, because it is selective, sensitive, precise, simple and fast.

The aim of this study was optimization and validation of RP-HPLC method with UV detection for determination of trace levels of corticosteroids in ambiphilic creams. This method is used for qualitative and quantitative analysis of evaluated corticosteroids.

Mometasone furoate, hydrocortisone acetate, fluocinonide, fluocinolone acetonide, betamethasone, betamethasone dipropionate and triamcinolone acetonide were evaluated. Separation was performed on Inertsil® ODS-3V 250 × 4.6 mm, 5 μm chromatographic column. Mobile phase was mixture of acetonitrile and water 50:50 (v/v) with gradient elution and flow rate 1 mL min−1. Column temperature was held on 40 °C and UV detection was performed at 240 nm.

Selectivity, linearity, accuracy, precision and limit of quantification (LOQ) were evaluated. Method is selective because ambiphilic cream base peaks and corticosteroids peaks were not overlapping. Linearity was confirmed since correlation coefficient was 1 for all compounds. Accuracy and precision were evaluated for hydrocortisone acetate and betamethasone dipropionate. Determined Recovery values were in range of 70–130%. Both RSD values (21.46% and 9.59%) were lower than 30%. Method is highly sensitive since LOQ concentrations were in ng mL−1 range.

All evaluated parameters of validation were in accordance with regulatory requirements. Validated RP-HPLC method can be used for qualitative and quantitative analysis of selected corticosteroids in ambiphilic creams.

Detection of 28 Corticosteroids in Pharmaceutical and Proprietary Chinese Medicinal Products Using Liquid Chromatography-Tandem Mass Spectrometry

With their potent anti-inflammatory effects, corticosteroids are popular adulterants in illicit health products for allergies, dermatitis and pain control. Their illegal supply over the counter is also a common practice for similar conditions. Prolonged, unsupervised usage of corticosteroids often leads to severe adverse effects including Cushing syndrome, adrenal insufficiency and immunosuppression. Confirming clinical suspicion of unsupervised corticosteroid usage is challenging. Apart from evaluating the adrenal function, identifying the concerned drug is the most direct proof of its consumption. While detecting corticosteroids or their metabolites in biological specimens is convincing evidence of their usage, such approach is analytically difficult. More importantly, this approach would not be useful if the patient has stopped taking the drug for some time-a situation that is often encountered clinically. We advocate a more direct approach by measuring corticosteroids in suspicious medicinal products. In the current study, a liquid chromatography-tandem mass spectrometry method for simultaneous detection of 28 corticosteroids in pharmaceutical and proprietary Chinese medicine products was developed and validated for the purpose. The method was applied to 388 cases of suspected unsupervised corticosteroids usage. Among 1,000 products tested, corticosteroids were found in 276 of them and confirmed the clinical suspicion.

Identification and characterization of unknown degradation impurities in beclomethasone dipropionate cream formulation using HPLC, ESI-MS and NMR

The present study focuses on identifying the degradation profile and pathways of unknown impurities from beclomethasone dipropionate (BDP) topical cream formulation reported under accelerated stability conditions. Six degradation impurities were observed during the accelerated stability testing of BDP topical cream formulation, and these thermally labile degradation impurities were primarily identified using a simple, effective and mass compatible isocratic reversed-phase high-performance liquid chromatography with ultraviolet detection method. The degradation impurities found in this sample were of very low concentration levels, thus the concentration of these impurities in the sample was enriched by mimicking the thermal degradation conditions to structurally elucidate the unknown impurities. These BDP thermal degradation impurities were isolated using preparative liquid chromatography and followed by pre-concentration using rota-vapour. Further, the collected thermal degradation impurities were characterized using ESI-MS, and the major impurity was identified using ¹H and C¹³ NMR spectroscopy, and DEPT technique. Plausible degradation pathway and mechanism of each impurity from BDP has been proposed based on the obtained mass and NMR spectral data. Thus, the present method is simple and suitable to be applied towards BDP assay in various formulations, and also to investigate the thermal stability and degradation kinetics of the final drug product.

Screening of counterfeit corticosteroid in creams and ointments by NMR spectroscopy

It has been shown that NMR spectroscopy is an effective analytical method to rapidly screen creams and ointments for counterfeit corticosteroids. Extraction and NMR procedures have been developed. Ten over the counter creams and ointments sold in health care shops were screened and two creams were found to contain counterfeited corticosteroids.

Ultra-Sensitive Quantification of Corticosteroids in Plasma Samples Using Selective Solid-Phase Extraction and Reversed-Phase Capillary High-Performance Liquid Chromatography/Tandem Mass Spectrometry

Low-dose corticosteroids may provide a favorable benefit/risk ratio for many therapeutic applications. However, the extremely low plasma drug concentrations achieved, in conjunction with the insufficient sensitivity/ selectivity of current analytical methods, renders the evaluation of corticosteroid pharmacokinetics (PK) a significant challenge under such conditions. Furthermore, targeted therapeutic strategies involving administration by inhalation or intraocular injection could result in very low but sustained systemic corticosteroid concentrations, which must be quantified to determine potential side effects. Here we describe a robust method for the ultrasensitive quantification of corticosteroids in plasma samples. This was achieved by the combination of a selective solid-phase extraction (SPE) with a highly sensitive capillary LC (microLC)-MS/MS analysis. SPE washing and elution conditions were optimized so that target drugs are selectively extracted from plasma. By eliminating most undesirable compounds from the sample matrix, this selective SPE procedure enabled a high sample loading volume on the microLC column without compromising chromatographic performance and operational robustness and helped to achieve ultralow detection limits for the corticosteroids in plasma. The effect of microLC separation on the signal-to-noise ratio of corticosteroid peaks in plasma samples was investigated. It was found that with sufficient microLC separation, sensitivity was improved because of a decrease in matrix effects and the removal of endogenous interferences. Detection limits of four clinically important corticosteroids (budesonide, dexamethasone, triamcinolone acetonide, and dexamethasone acetate) ranged from 0.2 to 1 pg/mL in plasma, and linearity was good for all drugs in the range of 5-5000 pg/mL. Accuracy was 88-107% and the variation (CV%) was 2.3-11.1%. A limit of quantification (LOQ) of 5 pg/mL was validated for all four compounds. We applied this method to quantify the low levels of triamcinolone acetonide (TACA) in porcine plasma following suprachoroidal administration, which is necessary to estimate systemic drug exposure resulting from this novel clinical approach for treating inflammatory diseases of the eye. TACA in plasma could be quantified at low pg/mL levels for up to 90 days posttreatment. To our knowledge, this is the first practical analytical approach that can monitor plasma corticosteroids after intraocular administration, given the ultralow plasma concentrations achieved. In summary, this strategy enables PK analysis of corticosteroids in treatment regimens that result in extremely low systemic concentrations, and the approach can be extended for the sensitive quantification of other drugs.

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.

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

A novel reversed-phase high-performance liquid chromatographic method with UV spectrophotometric detection was developed and validated for the determination of compounds in topical cream. The method describes determination of active component hydrocortisone acetate (HCA), its degradation products hydrocortisone (HC) and cortisone acetate (occurring in formulation after long-term stability tests) and two preservatives presented in the cream-methylparaben and propylparaben, using dexamethasone as an internal standard. The chromatographic separation was performed on a 5 microm SUPELCO Discovery C18 125 x 4-mm ID column. The optimised mobile phase for separation of all the compounds consists of methanol, acetonitrile and water (15:27:58, v/v/v), with the analysis time less than 13 min. The method was applicable for routine analysis (assays and stability tests) of active compound HCA, preservatives and degradation products in pharmaceutical product--topical cream Hydrocortizone cream 1%.