Chitosan Functionalization with Amino Acids Yields to Higher Copper Ions Adsorption Capacity

Author(s)

Mahl, Cynthia R. A. ^[1] ; Taketa, Thiago B. ^[1] ; Bataglioli, Rogerio A. ^[1] ; de Arruda, Eduardo Jose ^[2] ; Beppu, Marisa M. ^[1]

Affiliation

^[1] Univ Estadual Campinas, Fac Engn Quim, Ave Albert Einstein 500, BR-13083852 Campinas, SP - Brazil

^[2] Fundacao Univ Fed Grande Dourados, Rodovia Dourados Itahum, Km 12, BR-79804970 Dourados, MS - Brazil

• Document type: Journal article
• Source: JOURNAL OF POLYMERS AND THE ENVIRONMENT; v. 26, n. 12, p. 4338-4349, DEC 2018.
• Web of Science Citations: 4

Abstract

Chitosan (Chi) beads were conjugated with three different amino acids {[}namely, glutamic acid (GLU), methionine (MET), and taurine (TAU)] aiming to increase the divalent copper ions uptake in aqueous media. Scanning Electron Microscopy evidenced the development of a large porous structure after amino acid functionalization, associated with the increase in a number of amino groups in the polymer backbone. X-Ray Photoelectron Spectroscopy and Fourier-Transform Infrared Spectra analyses were also employed to assess the conjugation of these three different amino acids in chitosan backbone. Adsorption experiments were conducted in a batch process, at 298K, and kinetic data indicated a slightly better fitting for the pseudo-first-order model when compared to pseudo-second order. Intraparticle diffusion model suggested a three-step mechanism for Cu(II) adsorption kinetics, limited by the third step, the intraparticle diffusion. The isotherm data fitting to the traditional Langmuir and Freundlich models indicated a better fit for the former case. The amino acid conjugation resulted in the increase of the maximum adsorption capacity for Cu(II) from 1.30mmolg(-1) prior to amino acid conjugation to values as high as 2.31mmolg(-1), 2.40mmolg(-1) and 2.68mmolg(-1) for Chi-TAU, Chi-GLU, and Chi-MET, respectively. These results are attributed to the introduction of additional amino groups and new carboxylate and amino acid residues into the chitosan backbone, which might also be explored for amino acid demanding applications. (AU)

• FAPESP's process: 13/05135-1 - Nanostructured antimicrobial coatings containing chitosan produced by self-assembly technique (layer-by-layer) for textile substrates
• Grantee: Thiago Bezerra Taketa
• Support Opportunities: Scholarships in Brazil - Doctorate
• FAPESP's process: 16/10193-9 - New mechanisms for controlling triggered release of anticancer drugs in cellular backpacks
• Grantee: Rogério Aparecido Bataglioli
• Support Opportunities: Scholarships in Brazil - Doctorate (Direct)