Chromatographic method for clobetasol propionate determination in hair follicles and in different skin layers

Abstract

Clobetasol propionate (CLO) is a potent steroid used for the treatment of several dermatological diseases. Recent studies suggest its additional use in alopecia topical treatment, generating a demand for novel formulations with specific delivery into hair follicles. Hence, a selective analytical method for drug quantification in follicular structures and skin layers is required. For this, a simple HPLC-UV method was developed. Quantification was performed using a RP-C column (4.6 mm × 15 cm, 5 μm), with a mixture of methanol-acetonitrile-water (50:15:35 v/v) as mobile phase, a flow rate of 1.2 mL/min, oven temperature of 30°C, injection volume of 50 μL and detection at 240 nm. The optimized conditions enabled a 12 min running with CLO elution at 10.1 min and resolution of 2.424 from skin matrix interferences. Validation was performed in accordance with International Conference on Harmonization guidelines and fulfilled the criteria of selectivity, linearity (0.5-15.0 μg/mL), robustness, precision, accuracy and limits of detection and quantification (0.02 and 0.07 μg/mL, respectively). The validated method was successfully applied for CLO quantification following in vitro skin permeation experiments and differential tape-stripping for hair follicle deposition determination, demonstrating its suitability.

Simple and Selective HPLC-UV/Vis Bioanalytical Method to Determine Aluminum Phthalocyanine Chloride in Skin Permeation Studies

“…Interassay precision presented consistent responses for variation of the analyst, equipment, and day of analysis, with CV up to 7.8% for the lower concentration and less than 2% for the other concentrations ( Table 3 ). This result is in accordance with recommended limits of 15% established for bioanalytical methods [ 17 ].…”

“…In response surface graph shown in Figure 2 , peak area variation up to 8% is observed according to the flow rate. Similar effect is commonly described in the literature for other chromatographic methods [ 14 , 16 , 17 ], evidencing the importance of maintaining this parameter controlled and to perform periodical maintenance in the pumps. The predictive equation fitted a linear model and showed a high extrapolative capacity ( r 2 = 0.902).…”

Versatile chromatographic method for catechin determination in development of topical formulations containing natural extracts

“…Moreover, intermediate precision presented consistent responses for variation of analyst and day of analysis, with an overall CV of 5.5%. The result for these parameters is far below the limit of 15% established for bioanalytical methods (Angelo et al, ).…”

“…A negative interaction between FR and Temp was noticed (Figure B). The observed changes in retention time were expected since alterations in the polarity of the mobile phase necessarily modify the interaction of the analytes with the stationary phase (Angelo et al, ). Regarding this response, it is important to consider that, even when variations in retention time occur, the performance of the chromatographic method (tailing factor, theoretical plates and resolution) was preserved, guaranteeing the analysis.…”

“…Such experiment is imperative as a first screening tool to determine which formulations provide better skin bioavailability. The challenge is obviously to extract the marker from this complex biological matrix and selectively quantify it (Angelo, Cunha‐Filho, Gelfuso, & Gratieri, ). Second, along the industrial production of topical formulations, analytical methods to be used in stability assays are required to ensure product safety.…”