COMPARISON OF THE DETECTION AND QUANTITATIVE LIMITS OF HYDROCORTISONE ACETATE IN DIFFERENT CHROMATOGRAPHIC CONDITIONS IN TLC

Abstract

The detection (LOD), and quantification limits (LOQ) of hydrocortisone acetate in different conditions in TLC have been compared. Analysis has been performed using adsorption thin layer chromatography (NP-TLC) on chromatographic plates precoated with aluminum oxide 60 F₂₅₄, aluminum oxide 150 F₂₅₄, silica gel 60, silica gel 60 F₂₅₄, a mixture of silica gel, and kieselguhr 60 F₂₅₄ using chloroform + acetone + ammonia (25%) (8:2:0.1, v/v/v), and toluene + ethyl acetate (15:35, v/v) as well as reversed phase thin layer chromatography (RP-TLC) on the plates precoated with silica gel RP18 F₂₅₄, silica gel RP8 F₂₅₄ using the mixture of methanol + water in volume compositions 6:4 and 7:3. It has been proved that the stationary and mobile phase have a significant influence on the values of the detection limit (LOD), and quantification (LOQ) of hydrocortisone acetate in adsorption and partition thin layer chromatography. Using NP-TLC technique, the least amount of hydrocortisone acetate was detected and determined on plates precoated with aluminum oxide 150 F₂₅₄, and silica gel 60 using chloroform + acetone + ammonia (25%) in volume compositions 8:2:0.1 as a mobile phase. By means of RP-TLC technique, the least amount of hydrocortisone acetate was detected and determined on plates precoated with silica gel RP8 F₂₅₄. The detection limit (LOD) of hydrocortisone acetate determined by both TLC methods in nanogram range (51 ÷ 137 ng · spot⁻¹) indicates that thin layer chromatography combined with densitometry may be an alternative method to the modern chromatographic techniques for hydrocortisone acetate detection.

Keywords:

• densitometry
• detection limit
• hydrocortisone acetate
• NP-TLC
• quantification limit
• RP-TLC

Notes

^a Mobile phase: A) chloroform + acetone + ammonia (25%) (8:2:0.1, v/v/v); and B) toluene + ethyl acetate (15:35, v/v).

^a Mobile phase: C) methanol + water (6:4, v/v); and D) methanol + water (7:3, v/v).

^a Mobile phase: A) chloroform + acetone + ammonia (25%) (8:2:0.1, v/v/v); B) toluene + ethyl acetate (15:35, v/v); C) methanol + water (6:4, v/v); D) methanol + water (7:3, v/v).

S_a, standard deviation of the intercept of a calibration curve; S_xy, residual standard deviation of a calibration curve.