Preparation and characterisation of surfaces properties of poly(hydroxyethylmethacrylate-co-methacrylolyamido-histidine) membranes: application for purification of human immunoglobulin G

Yılmaz

2009

Bioprocess Biosyst Eng

112

Cross-linked magnetic chitosan beads were prepared by phase-inversion technique in the presence of epichlorohydrin under alkaline condition, and used for covalent immobilization of laccase. The activity of the immobilized laccase on the magnetic chitosan was about 260 U (g/dry beads) with an enzyme loading of about 16.33 +/- 0.39 mg [(g/dry beads) mg/g]. Kinetic parameters, V (max) and K (m) values were determined as 21.7 U/mg protein and 9.4 microM for free enzyme, and 15.6 U/mg protein and 19.7 microM for the immobilized laccase, respectively. The operational and thermal stabilities of the immobilized laccase were improved compared to free counterpart. The immobilized laccase was operated in a batch reactor for the decolorization of reactive dyes from aqueous solution. The laccase immobilized on magnetic chitosan beads was very effective for removal of textile dyes from aqueous solution which creates an important environmental problem in the discharged textile dying solutions.

Section: Optimization Of Reaction Conditions Of Free and Immobilized mentioning

confidence: 99%

Preparation and characterization of epoxy-functionalized magnetic chitosan beads: laccase immobilized for degradation of reactive dyes

Yılmaz

2009

Bioprocess Biosyst Eng

112

“…To optimize the catalytic efficiency and stability of the resulting enzyme-polymer, the attempt was made to understand the immobilization effects on enzymatic properties. The levels of activity decrease and diffusion limitation caused by immobilization are mainly dependent on the properties of support and immobilization conditions [14][15][16][17]. Many efforts have been made on modifying the carriers, in order to make the carriers more suitable for enzyme immobilization.…”

Section: Introductionmentioning

confidence: 99%

Reversible immobilization of Candida rugosa lipase on fibrous polymer grafted and sulfonated p(HEMA/EGDMA) beads

Soydogan

2009

Bioprocess Biosyst Eng

Poly(2-hydroxyethyl methacrylate/ethylenglycol dimethacrylate) beads were grafted with poly(glycidylmethacrylate) via surface initiated atom transfer radical polymerization. Epoxy groups of the grafted polymer were modified in to sulfone groups. Sulfonated beads were characterized by swelling studies, FT-IR, SEM and elemental analysis, and were used for reversible immobilization of lipase. Under given experimental conditions, the beads had an adsorption capacity of 44.7 mg protein/g beads. The adsorbed lipase on beads retained up to 67.4% of its initial activity. The immobilized lipase exhibited improved thermal and storage stabilities over those of the free enzyme. The immobilized lipase could desorb 1.0 M NaCl solution at pH 8.0, and the sulfonated beads can be repeatedly charged with fresh enzyme after inactivation upon use.

“…In the previous studies, different types of affinity ligand molecules, such as triazidine dyes, 11,12 immobilized metal ions, 5,13 and L-histidine amino acid, 14,15 have been used for adsorption and purification of proteins. In the present work, epoxy group containing poly(GMA/MMA/EGDMA) beads were prepared by suspension polymerization.…”

Section: Introductionmentioning

confidence: 99%

Adsorption of IgG on spacer‐arm and L‐arginine ligand attached poly(GMA/MMA/EGDMA) beads

Şenel

J of Applied Polymer Sci

2007

Self Cite

This work presents data on human immunoglobulin G (HIgG) adsorption onto L‐arginine ligand attached poly(GMA/MMA/EGDMA)‐based affinity beads which were synthesized from methyl methacrylate (MMA) and glycidiyl methacrylate (GMA) in the presence of a crosslinker (i.e., ethylene glycol dimethacrylate; EGDMA) by suspension polymerization. The epoxy groups of the poly(GMA/MMA/EGDMA) beads were converted into amino groups after reaction with ammonia or 1,6‐diaminohexane (i.e., spacer‐arm). With L‐arginine as a ligand, it was covalently immobilized on the aminated (poly(GMA/MMA/EGDMA)‐ AA) and/or the spacer‐arm attached (poly(GMA/MMA/EGDMA)‐SA) beads, using glutaric dialdehyde as a coupling agent. Both affinity poly(GMA/MMA/EGDMA)‐based beads were used in HIgG adsorption/desorption studies under defined pH, ionic strength, or temperature conditions in a batch reactor, using acid‐treated poly(GMA/MMA/EGDMA) beads as a control system. The poly(GMA/MMA/EGDMA)‐SA affinity beads resulted in an increase in the adsorption capacity to HIgG compared with the aminated counterpart (i.e., poly(GMA/MMA/EGDMA)‐AA). The maximum adsorption capacities of the poly(GMA/MMA/EGDMA)‐AA and poly(GMA/MMA/EGDMA)‐SA affinity beads were found to be 112.36 and 142 mg g−1, and the affinity constants (Kd), evaluated by the Langmuir model, were 2.48 × 10−7 and 6.98 × 10−7M, respectively. Adsorption capacities of the poly(GMA/MMA/EGDMA)‐AA and poly(GMA/MMA/EGDMA)‐SA were decreased with HIgG by increasing the ionic strength adjusted with NaCl. Adsorption kinetic of HIgG onto both affinity adsorbents was analyzed with first‐ and second‐order kinetic equations. The first‐order equation fitted well with the experimental data. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 672–679, 2007