Eco-Friendly Chromatographic Methods for Determination of Acemetacin and Indomethacin; Greenness Profile Assessment

Background: The green chemistry approach was developed for the purpose of saving the environment by using green solvents. Applying green analytical chemistry principles to traditional methods is considered a challenge. Acemetacin is a commonly used analgesic prodrug that bioactivates to indomethacin. Objective: Developing two simple, eco-friendly chromatographic methods for simultaneous determination of acemetacin and indomethacin. Method: The first method is HPLC-DAD. Separation was performed on a Waters XBridge((R)) Shield RP18 (250x4.6mm, 5 mu m) analytical column with ethanol-ammonium acetate buffer (50mM, pH 3.50.1; 60:40, v/v) as a mobile phase at a flow rate of 1mL/min at 250.5 degrees C and UV detection at 254nm. The other method is TLC coupled with densitometric quantification using pre-coated silica TLC plates and butanol-ethyl acetate (70:30, v/v) elution system. The plates were scanned at 254nm. Results: Both methods were validated according to International Conference on Harmonization guidelines. Linearity was confirmed for both over a concentration range of 1-100 mu g/mL for the HPLC method and 0.2-7 mu g/band for TLC-densitometric method. The methods' greenness was evaluated by the National Environmental Methods Index, Eco-Scale, Green Analytical Procedure Index metrics and Analytical GREEnness Metric Approach. Conclusions: The proposed methods were found to be suitable for determination of studied drugs in their marketed formulations and is suggested for routine analysis in quality control laboratories. Highlights: The developed HPLC method shortened the elution time of the analyzed drugs saving more time and money and the TLC method lowered the drugs' detection limit. HPLC and TLC methods were validated for the assay of acemetacin and indomethacin. The methods' greenness was evaluated and compared to published methods. The developed HPLC method shortened the elution time of the analyzed drugs, saving time and money and the TLC method lowered the drugs' detection limit.