AIM: To extract codeine and paracetamol from its tablet by solvent extraction and tentatively identify in comparison to standards using Thin Layer Chromatography.
INTRODUCTION:
Codeine or methyl morphine, an alkaloid, was first isolated in 1832 from raw opium. It concentration ranges from 0.2% to 0.8%. Mostly used for its analgesic, anti-tussive and anti-diarrheal capabilities (Tremlett, Anderson and Wolf, 2010). Paracetamol also known as acetaminophen (n-acetyl-p-aminophenol, APAP) on the other hand, is a useful non- steroidal anti- inflammatory drug (NSAID). It is commonly used in the management of pain and fever in a variety of patients (Kamberi, et al., 2004).
Fig 1: Codeine[NCBI, 2009] Fig 2: Acetaminophen[NCBI, 2009]
One of the technique involved in the extraction of codeine and paracetamol from its matrix, is the solvent extraction otherwise known as liquid – liquid extraction. This process entails the use of two immiscible liquids usually chloroform and water; in dissolving the sample for two distinctive layers to form after the mixture had been thoroughly shaken together (Rubinson and Rubinson, 1998).
Separating the components of the extract, is done through the use of Thin Layer Chromatography. It is one of the standard procedures used in many forensic laboratory when analysizing unknown drugs or mixtures (Howlett and Steiner, 2011). Separation of the mixtures occur based on the pH, polarity of its components, solvent and the thin layer stationary phase (Howlett and Steiner, 2011).
METHODS:
The finely divided sample was dissolved in 20ml of distilled water. This was then basified with NaOH solution to pH 12 using litmus paper. The resulting solution was later filtered. 1.0ml of chloroform
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