Adsorption of biomolecules in porous silicas modified with zirconium. Effect of the textural properties and acidity

• Published in: Microporous and mesoporous materials 2018-04, Vol.260, p.146-154
• Main Authors: Santos, Sandra M.L., Cecilia, Juan A., Vilarrasa-García, Enrique, García-Sancho, Cristina, Silva Junior, Ivanildo J., Rodríguez-Castellón, Enrique, Azevedo, Diana C.S.
• Format: Article
• Language: English
• Subjects: Adsorption; Bovine serum albumin; Cellulase; Porous silica; Zr doping
• ISSN: 1387-1811; 1873-3093
• DOI: 10.1016/j.micromeso.2017.10.044

The traditional SBA-15 was modified using pore 1,3,5-trimethylbenzene as pore expander to be evaluated in the adsorption of biomolecules bovine serum albumin (BSA) and cellulase (CEL). In order to study the influence of the acidity in the biomolecules adsorption, porous silicas with molar ratio in a range between 5 and 15 were synthesized. The obtained materials were characterized by X-ray diffraction, transmission electron microscopy, N2 adsorption-desorption at -196 °C, NH3 thermoprogrammed desorption, infrared spectroscopy and X-ray photoelectron spectroscopy. Then, their adsorption capacity for BSA and CEL was evaluated in batch experiments at 25 °C. The obtained data revealed that BSA adsorption is well-fitted to the Toth model in all adsorbents, while CEL adsorption is well-adjusted to the Henry model. In both cases, the adsorbent with a molar ratio Si/Zr = 15 and pore expander reached the highest adsorption values and showed high desorption capacity. [Display omitted] •Pore expanded-SBA-15 displays higher adsorption capacity.•The incorporation of Zr into the SBA-15 increase the biomolecules adsorption.•BSA reaches the highest value for expanded porous silica with a Si/Zr = 15.•Isotherm profiles indicates that cellulase adsorption is weaker than BSA one.•The biomolecules desorption is limited by the acidity of the adsorbent.