Context: Calcareous chitin, chitin, chitosan, and their modifications are used as bioadsorbents of metals and dyes that cause environmental pollution, endocrine disruption, and human diseases. Aims: To evaluate the selective bioadsorption of silver ions (Ag+) by calcareous chitin, chitin, and chitosan. Methods: Experimental and prospective study. The presence of functional groups of the bioadsorbents was identified by Fourier-transformed infrared spectroscopy (FT-IR), 1H-NMR spectroscopy and scanning electron microscopy (SEM). The Langmuir, Freundlich, and Elovich models were applied to describe the adsorption capacity of bioadsorbents according to granule size (20-40, 40-60, 60-80 meshes) and temperature (10, 20, and 30°C). Results: The FT-IR spectrum of calcareous chitin indicates the presence of carbonate (CO3= 1420 cm-1), amide III (1313 cm-1), –OH groups (3441.90 cm-1), and pyranose structure (952.83 cm-1); chitin has –OH groups (3441.90 cm-1), NH (3268 cm-1), amide I (1654 cm-1) and II (1559 cm-1); chitosan has –OH groups (3419.90 cm-1), –NH (3200 cm-1), amide I (1712.18 cm-1), –NH2 (1654.46 cm-1), amide III (1317.11 cm-1) and pyranose structure (1070.12 cm-1 and 1031 cm-1). The Langmuir model indicates greater bioadsorption of Ag+ ions at smaller particle sizes (60-80 = 0.25-0.18 mm) and at a temperature of 20-30°C. Conclusions: The bioadsorption of silver ions (Ag+) by chitosan is greater with respect to calcareous chitin and chitin; the Langmuir model fits for the Ag+ isotherm and suggests that the process is controlled by physisorption.
|Translated title of the contribution||Bioadsorption of silver ions by calcareous chitin, chitin and chitosan|
|Number of pages||9|
|Journal||Journal of Pharmacy and Pharmacognosy Research|
|State||Published - Jan 2023|
Bibliographical noteFunding Information:
The authors thank the members of the Molecular Pharmacology Society of Peru for their participation in this study. This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors.
© 2023 Journal of Pharmacy & Pharmacognosy Research.