A sensitive, simple, accurate, and economic thin-layer chromatographic method has been established for analysis of negundoside in leaf powder of
Linn. A methanol extract of the leaf powder was used for the experimental work. Separation was performed on aluminum-backed silica gel 60 F
HPTLC plates with ethyl acetate-methanol-water-glacial acetic acid 7.8:1.2:0.7:0.3 as mobile phase. After development, quantification was performed by densitometry at 267 nm. The limits of detection and quantitation were 0.4 and 1.2 μg mL
, respectively. The response was linearly dependent on the amount of negundoside in the range 1.2 to 22.5 μg mL
. The regression coefficient for negundoside was 0.9998. The validated TLC densitometric method can be used for routine quality-control analysis of
leaf powder and for quantitative analysis of negundoside.
A simple, precise, rapid, selective, and cost-effective high-performance thin-layer chromatographic (HPTLC) method has been established for simultaneous estimation of curcumin, piperine, and thymol in an ayurvedic formulation. Chromatography was performed on silica gel 60 F
plates with toluene-ethyl acetate-methanol, 9 + 1 + 0.5 (
), as mobile phase. Plates were developed to a distance of 8 cm at room temperature, without chamber saturation. The plates were scanned and the compounds were quantified at their wavelengths of maximum absorption, 420, 333, and 277 nm for curcumin, piperine, and thymol, respectively. The respective
values of curcumin, piperine, and thymol were 0.23, 0.30, and 0.64. Response was a linear function of the amount applied to the plate in the ranges 50–250 ng, 10–60 ng, and 100–700 ng for curcumin, piperine, and thymol, respectively. LOD for curcumin, piperine, and thymol were 25, 5, and 50 ng, respectively. The mean results from assay of curcumin, piperine, and thymol in the ayurvedic formulation were found to be 0.85, 12.93, and 3.29 mg g
, respectively. The respective covariance for curcumin, piperine, and thymol was 0.78, 0.51, and 0.69%, respectively. Recovery was 100.41, 99.52, and 101.21% for curcumin, piperine and thymol, respectively. Rapid identification of curcumin, piperine, and thymol is also possible by spraying the plate with anisaldehyde in sulfuric acid reagent.