Implementation Of Hydrotropic Solvents for Uv Spectrophotometric Assessment of Telmisartan and Indomethacin: A Green Analytical Approach

UV-visible spectrophotometry is a widely used analytical technique in pharmaceutical analysis due to its simplicity, accuracy, rapidity, and cost-effectiveness.[1] However, the estimation of poorly water-soluble drugs often requires organic solvents such as methanol and ethanol, which are associated with toxicity, environmental hazards, and disposal challenges.[2]Hydrotropy is an effective solubilization technique that enhances the aqueous solubility of poorly soluble drugs through the use of hydrotropic agents such as urea, sodium benzoate, and nicotinamide. These agents provide a safer, economical, and environmentally friendly alternative to conventional organic solvents.[3]

Telmisartan, an angiotensin II receptor blocker, and Indomethacin, a non-steroidal anti-inflammatory drug, are both poorly water-soluble drugs that present difficulties in routine spectrophotometric analysis.[4] The present study explores the use of 2 M urea as a hydrotropic solvent for the UV spectrophotometric estimation of Telmisartan and Indomethacin.[5] The method aims to reduce the use of hazardous organic solvents while maintaining analytical accuracy, precision, and reliability. Additionally, the greenness of the developed analytical procedure was evaluated in accordance with Green Analytical Chemistry principles, highlighting its suitability for sustainable pharmaceutical analysis.[6]

 

 

Figure 1. Chemical Structures of Telmisartan and Indomethacin

 

 

Figure 2. UV Absorption Spectra of Telmisartan and Indomethacin in 2 M Urea Solution Showing λmax at 240 nm and 320 nm, Respectively.

Table 1. Calibration Data of Telmisartan in 2 M Urea Solution at 240 nm

Concentration (μg/mL)	Absorbance
10	0.103
20	0.197
30	0.303
40	0.410
50	0.523
60	0.632
70	0.709
80	0.805
90	0.886
100	0.987

Regression coefficient (R²) = 0.9978

 

 

Figure 3. Calibration Curve of Telmisartan in 2 M Urea Solution

Table 2.Calibration Data of Indomethacin in 2 M Urea Solution at 320 nm

Concentration (μg/mL)	Absorbance
10	0.110
20	0.251
30	0.405
40	0.552
50	0.692
60	0.820
70	0.990
80	1.200
90	1.300
100	1.400

Regression coefficient (R²) = 0.9968

 

 

Figure 4. Calibration

Curve of Indomethacin in 2 M Urea Solution

The calibration curves followed Beer-Lambert’s law over the selected concentration range, indicating excellent linearity and suitability for quantitative estimation.

CONCLUSION

The study successfully demonstrated the application of hydrotropic solubilization for UV spectrophotometric determination of Telmisartan and Indomethacin. A 2 M urea solution effectively enhanced the aqueous solubility of both drugs without affecting their spectral characteristics. The developed methods exhibited excellent linearity, simplicity, accuracy, and reproducibility. Furthermore, the replacement of conventional organic solvents with urea represents a greener and safer analytical alternative. The proposed approach is suitable for routine pharmaceutical quality control and supports sustainable analytical chemistry practices.

REFERENCES

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