Mesocellular Silica Foams (MCFs) with Tunable Pore Size as a Support for Lysozyme Immobilization: Adsorption Equilibrium and Kinetics, Biocomposite Properties

Abstract

The effect of the porous structure of mesocellular silica foams (MCFs) on the lysozyme (LYS) adsorption capacity, as well as the rate, was studied to design the effective sorbent for potential applications as the carriers of biomolecules. The structural (N2 adsorption/desorption isotherms), textural (SEM, TEM), acid-base (potentiometric titration), adsorption properties, and thermal characteristics of the obtained lysozyme/silica composites were studied. The protein adsorption equilibrium and kinetics showed significant dependence on silica pore size. For instance, LYS adsorption uptake on MCF-6.4 support (pore diameter 6.4 nm) was about 0.29 g/g. The equilibrium loading amount of LYS on MCF-14.5 material (pore size 14.5 nm) increased to 0.55 g/g. However, when the pore diameter was larger than 14.5 nm, the LYS adsorption value systematically decreased with increasing pore size (e.g., for MCF-30.1 was only 0.27 g/g). The electrostatic attractive interactions between the positively charged lysozyme (at pH = 7.4) and the negatively charged silica played a significant role in the immobilization process. The differences in protein adsorption and surface morphology for the biocomposites of various pore sizes were found. The thermal behavior of the studied bio/systems was conducted by TG/DSC/FTIR/MS coupled method. It was found that the thermal degradation of lysozyme/silica composites was a double-stage process in the temperature range 165–420–830 °C.

Carbon Molecular Sieve Membranes Comprising Graphene Oxides and Porous Carbon for CO2/N2 Separation

“…Such enhancement can be possibly explained with the aid of micropore size distribution as reported in Figure 8 c,d (in which the profiles were calculated from CO 2 adsorption at 0 °C as reported in Figure S8 ). In general, the presence of additional micropores that are smaller than the pores in pure CMSM potentially contributes to an improved CO 2 /N 2 selectivity [ 39 , 40 ]. Indeed, the presence of the smaller micropores was observed in the pore size distribution of mixed-matrix CMSMs ( Figure S9 ).…”

Physicochemical and Adsorption Characteristics of Divinylbenzene-co-Triethoxyvinylsilane Microspheres as Materials for the Removal of Organic Compounds

“…The Pore Diffusion Model (PDM, McKay) describe adsorption on porous solids which combines the transfer resistance of adsorbate particles through the surface layer, the proportional penetration of the adsorbate into the adsorbent grains, the sharp boundary between the space in which the equilibrium state is determined and the space without the adsorbate, and can be expressed by the mathematic formula: where u eq is the relative adsorbate loss, the parameter B = 1 − 1/ B i and B i = K f / D p is the Biot number, D p is the pore diffusion coefficient, K f is the external mass transfer coefficient, τ s is the undersized model time [ 32 , 56 , 57 ].…”

The Physical Chemistry and Chemical Physics (PCCP) Section of the International Journal of Molecular Sciences in Its Publications: The First 300 Thematic Articles in the First 3 Years

“…In this Thematic Area, 56 articles have been published [ 48 , 64 , 104 , 108 , 110 , 124 , 195 , 252 , 253 , 254 , 255 , 256 , 257 , 258 , 259 , 260 , 261 , 262 , 263 , 264 , 265 , 266 , 267 , 268 , 269 , 270 , 271 , 272 , 273 , 274 , 275 , 276 , 277 , 278 , 279 , 280 , 281 , 282 , 283 , 284 , 285 , 286 , 287 , 288 , 289 , 290 , 291 , 292 , 293 , 294 , 295 , 296 , 297 , 298 , 299 , 300 ], an...…”

“…The processes in inorganic nanomaterials were considered in one way or another, in articles [ 104 , 108 , 110 , 252 , 253 , 264 , 265 , 267 , 268 , 269 , 270 , 275 , 276 , 279 , 281 , 285 , 286 , 287 , 297 ]. Additionally, here, the materials in which these processes are implemented are very diverse.…”