Simple Analytical Method on the Determination of Dexamethasone in Herbal Medicine

Abstract

Chemical drugs have been added to some of the traditional herbal medicine to enhance the therapeutic effect. One of them is dexamethasone which is added in herbal pain relief. To determine the content of dexamethasone in herbal medicine, a quantitative analytical method was developed with the reaction of the formation of a dexamethasone-hydroxylamine complex with fluoranil which was measured by UV-Vis spectrophotometry. Under optimized conditions, the performance of this system to analyze dexamethasone exhibited a good analytical response. The correlation coefficient was (R2) of 0.9965 from a concentration of 1–40 g/mL, LOD, and LOQ of 0.21 μg/mL and 0.64 μg/mL, % recovery for concentrations of 80%,100%, and 120%, are 100.14% ± 0.58; 98.35% ± 1.19; and 99.00% ± 1.18, respectively; and %RSD is 0.75%. The sixteen herbal medicine samples were analyzed to confirm the application of this method. The result showed six samples confirmed containing dexamethasone with levels ranging from 7.44 to 21.61 μg/mL and confirmed with HPLC data. The UV-Vis spectrophotometry method is simple and effective for dexamethasone analysis in herbal medicine.

A Polymer-Based Indicator for Detecting Dexamethasone in Herbal Medicine Using Polymethylmethacrylate (PMMA)

“…Then, they were stirred with a shaker at 90 rpm for 30 min. This solvent combination was used in previous studies to detect dexamethasone and showed good results, so the same combination was also used to extract dexamethasone in the herbal samples here [12]. The stirring process also served to ensure that the dexamethasone in the herbal samples could be optimally extracted.…”

“…These conditions indicated that there was a peak of dexamethasone at a retention time of 3.501 min with the UV detector at a wavelength of 240 nm, as shown in Figure S1. The conditions were optimized by fulfilling the parameters of the validation method, so the results of analyses using these conditions would show a proper detection of dexamethasone [12]. To be able to determine the level of dexamethasone in the sample, it was necessary to prepare a standard curve by using the dexamethasone standard in various concentrations.…”

“…Dexamethasone can be detected in herbal medicine by using standardized methods of high-performance liquid chromatography (HPLC) with the procedures listed in the pharmacopeia [11]. Another method that has been developed to detect dexamethasone in herbal medicine is using UV-Vis spectrophotometry by firstly forming a dexamethasonehydroxylamine complex so that it can be detected with a UV-Vis spectrophotometer, but the formation of this complex requires a quite complicated procedure before dexamethasone can be detected via UV-Vis spectrophotometry [12]. Dexamethasone can also be detected by using a simpler method-thin-layer chromatography (TLC)-densitometry-as described by Permatasari et al Asra et al conducted research by using the high-performance thinlayer chromatography (HPTLC)-densitometry method as an advanced form of TLC, which offered better resolution and faster detection than TLC due to the use of silica gel with a very small size compared to that used in TLC [13,14].…”