[Fluorescence studies on amoxicillin]

Area of Science:

• Analytical Chemistry
• Pharmaceutical Analysis
• Spectroscopy

Background:

• Amoxicillin is a widely used antibiotic.
• Understanding its physicochemical properties is crucial for accurate quantification and stability assessment.
• Fluorescence spectroscopy offers a sensitive method for analyzing amoxicillin.

Purpose of the Study:

• To investigate the influence of pH, organic solvents, and surfactants on amoxicillin's fluorescence.
• To establish a quantitative fluorescence method for amoxicillin.
• To explore potential interactions between amoxicillin and metal ions.

Main Methods:

• Amoxicillin fluorescence was measured across varying pH conditions and in the presence of organic solvents (acetone, methanol, ethanol) and a surfactant (CTAB).
• A calibration curve was generated to determine linearity and regression coefficients.
• Fluorescence spectra were recorded for amoxicillin in the presence of metal ions (Mg2+, Ca2+, Al3+, Ga3+) at pH 12.

Main Results:

• Amoxicillin displayed strong fluorescence emission at pH 8, with excitation and emission wavelengths of 277 nm and 303 nm, respectively.
• A linear relationship was observed between amoxicillin concentration (2 x 10(-5) to 2 x 10(-4) mol/L) and fluorescence intensity (R=0.9996).
• CTAB enhanced amoxicillin's fluorescence intensity, and interactions with Mg2+, Ca2+, Al3+, and Ga3+ were detected at pH 12.

Conclusions:

• Optimal fluorescence detection of amoxicillin is achieved in a pH 8 buffer.
• The established fluorescence method is reliable for quantifying amoxicillin within the tested concentration range.
• Amoxicillin interacts with certain metal ions, indicating potential implications for its formulation and stability.