[Study on extractive spectrophotometry for determination of amoxicillin with ionic associate]

Area of Science:

• Analytical Chemistry
• Spectroscopy

Context:

• Accurate quantification of amoxicillin (AMO) is crucial for pharmaceutical quality control and clinical monitoring.
• Existing methods may require complex procedures or lack sensitivity for certain applications.

Purpose:

• To develop and validate a simple, sensitive, and reliable extractive spectrophotometric method for amoxicillin determination.
• To establish the optimal conditions for the formation and extraction of the amoxicillin-methylene blue ion pair complex.

Summary:

• A novel extractive spectrophotometry method utilizes the ion pair complex formed between amoxicillin (AMO) and methylene blue (MB).
• The complex is extracted into 1,2-dichloroethane at pH 3.3, exhibiting maximum absorption at 657 nm.
• The method demonstrates a 1:1 molar ratio, high apparent molar absorptivity (5.0 x 10^4 L mol⁻¹ cm⁻¹), linearity (0.4–6.8 mg L⁻¹), a low detection limit (0.01 mg L⁻¹), and excellent recovery rates (97.5%–101.3%).

Impact:

• Provides a validated analytical tool for the accurate determination of amoxicillin in pharmaceutical formulations.
• Enables reliable quantification of amoxicillin in biological matrices such as urine samples.
• Offers a cost-effective and efficient alternative for amoxicillin analysis in various settings.