Introducing ATR-FTIR Spectroscopy through Analysis of Acetaminophen Drugs: Practical Lessons for Interdisciplinary and Progressive Learning for Undergraduate Students

• Published in: Journal of Chemical Education Vol. 98; no. 8; pp. 2675 - 2686
• Main Authors: Zapata, Félix, López-Fernández, Adrián, Ortega-Ojeda, Fernando, Quintanilla, Gloria, García-Ruiz, Carmen, Montalvo, Gemma
• Format: Journal Article
• Language: English
• Published: United States American Chemical Society and Division of Chemical Education, Inc 10.08.2021; American Chemical Society (ACS); Division of Chemical Education, Inc; American Chemical Society
• Subjects: Analgesics; Analytical Chemistry; Chemistry; Chemometrics; College Science; College students; Colleges & universities; Counterfeit; Drugs; Drugs/Pharmaceuticals; Forensic Chemistry; Forensic science; Graduate students; Hands-On Learning/Manipulatives; Identification; Infrared analysis; Infrared spectroscopy; Interdisciplinary Approach; IR Spectroscopy; Laboratory Equipment/Apparatus; Laboratory Experiment; Laboratory Experiments; Learning; Narcotics; Organic Chemistry; Pharmacy; Qualitative Analysis; Quality control; Química; Science Experiments; Science Instruction; Science Laboratories; Scientific Research; Spectra; Spectral bands; Spectroscopy; Spectrum analysis; Statistical analysis; Students; Studies; Undergraduate Research; Undergraduate Students; Undergraduate study; Upper-Division Undergraduate; Hands-On Learning/Manipulatives; Upper-Division Undergraduate; Analytical Chemistry; Forensic Chemistry; Qualitative Analysis; IR Spectroscopy; Laboratory Equipment/Apparatus; Undergraduate Research; Drugs/Pharmaceuticals; Chemometrics
• ISSN: 0021-9584; 1938-1328
• DOI: 10.1021/acs.jchemed.0c01231

Infrared (IR) spectroscopy is a vibrational spectroscopic technique useful in chemical, pharmaceutical, and forensic sciences. It is essential to identify chemicals for reasons spanning from scientific research and academic practices to quality control in companies. However, in some university degrees, graduate students do not get the proficiency to optimize the experimental parameters to obtain the best IR spectra; to correlate the IR spectral bands with the molecular vibrations (chemical elucidation); to have some criteria for any substance identification (especially relevant in quality control to recognize counterfeit); and to apply chemometrics for comparing, visualizing, and classifying the IR spectra. This work presents an experimental laboratory practice for an introductory teaching of the IR instrumental conditions in the identification of substances based on visual spectra comparison and statistical analysis and matching. Then, the selected IR conditions are applied to different commercial drugs, in the solid state or in solution, mostly composed of acetaminophen. Finally, the students apply chemometrics analysis to the IR data. This practice was designed for the training in a chemistry subject for undergraduate students of the chemistry, pharmacy, or forensics degrees, among others related to science, medical, food, or technological sciences.