Radiation-modified wool for adsorption of redox metals and potentially for nanoparticles

Abstract

Electron beam irradiated sheep wool with absorbed radiation doses ranging from 0 to 165 kGy showed good adsorption properties toward copper cations. The Cu(ii) being Lewis acid generated several types of complex salts based on carboxylates or cysteinates with ligands available in keratin. Under these conditions, cross-links were formed between the keratin chains. Experimental data obtained from Cu(ii) adsorption using the concentration of 800–5,000 mg/L were tested for fitting to 10 isotherm models. Various compositions and architectures of the Cu(ii)-complexes were specified to be responsible for different isotherm model fittings. The copper cation showed adherence to Langmuir, Flory–Huggins, and partially Redlich–Peterson models. The latter clearly distinguished the native wool from the modified ones. Another aim is to investigate the conditions for the adsorption of anti-microbial nanoparticles in addition to the redox-active metals on radiation-modified wool taking into account that the diffusion of nanoparticles into the modified wool is governed by electrostatic interactions.

The Application of Sheep Wool in the Building Industry and in the Removal of Pollutants from the Environment

“…All mentioned cations are complexforming. In the analysis of Co(II)'s fitting for 10 models of adsorption isotherms [53], agreements with the Langmuir, Flory-Huggins and Redlich-Peterson models were shown. When comparing the results with those of the models applied for Cr(III), it was found that none of the 10 models were adequate for both Cr(III) and Co(II).…”

“…The copper cation showed adherence to Langmuir, Flory-H and partially Redlich-Peterson models. The latter clearly distinguished the nati from the modified ones [53].…”

Prewetting Electron Beam Irradiated and Native Sheep Wool Can Affect Their Sorptivity

“…Prewetting for 24 h compared to the corresponding non-prewetted sample after 1 h contact increased the sorptivity for 0 kGy by 55%, 48 kGy by 120%, and 153 kGy up to 170%. In the adsorption isotherm fitting test, chemisorption was confirmed in the case of Cu adsorption by applying the Flory-Huggins model [29]. In chemisorption, the Cu(II) cation reacts with the R-COOH groups on the keratin side chains (such as aspartic acid, glutamic acid, and cysteine) to form Cu-salts.…”

“…In the adsorption isotherm fitting test, chemisorption was confirmed in the case of Cu adsorption by applying the Flory-Huggins model [29]. In chemisorption, the Cu(II) cation reacts with the R-COOH groups on the keratin side chains (such as aspartic acid, glutamic acid, and cysteine) to form Cu-salts.…”

From Strain Stiffening to Softening—Rheological Characterization of Keratins 8 and 18 Networks Crosslinked via Electron Irradiation

“…However, it was shown that the effect of irradiation is complex, and each dose may provoke different effects on the wool keratin structure [ 35 ]. Furthermore, several studies reported the improvement of the sorption affinity of wool keratin towards some metal cations and therefore its usefulness in environmental cleaning [ 36 , 37 , 38 , 39 , 40 ]. In a previous attempt to prepare biocompatible hair and wool keratins hydrogels via EBI, a blend with synthetic polymers was necessary to obtain a gel after irradiation [ 41 ].…”