Comparative Evaluation of Paracetamol Tablet Formulations from Different Manufacturers in the Libyan Pharmaceutical Market Using Fourier-Transform Infrared (FTIR) Spectroscopy

Abstract

Paracetamol (N-acetyl-p-aminophenol) is one of the most widely used over-the-counter analgesic and antipyretic medications globally. To ensure quality control, therapeutic efficacy, and detect potential counterfeiting, rigorous analytical evaluation of commercial formulations from various global manufacturing sites is critical. This study employs Fourier-Transform Infrared (FTIR) spectroscopy to perform a comparative evaluation of the chemical integrity and structural equivalence of standard Paracetamol (C8H9NO2) against three commercial Panadol 500 mg formulations manufactured by Bristol Laboratories (United Kingdom) and GSK (Tunisia and Ireland plants). The results demonstrate high structural correlation with matching scores ranging from 93.7% to 95.6% relative to the reference standard. Spectral analysis confirmed characteristic functional groups, including amide carbonyl stretches, aromatic ring vibrations, and hydroxyl/amine stretching zones, corroborating that all sampled manufacturers meet stringent chemical identity requirements.