Dye-affinity hollow-fibres and their lysozyme adsorption-desorption characteristics

Dye-affinity adsorption is increasingly used for protein separation. Hollow -fibres have advantages as adsorbents in comparison to conventional bead su pports because they are not compressible and can eliminate internal diffusi on limitations. The aim of this study was to explore in detail the performa nce of polyamide hollow-fibres to which Reactive Green HE-4BD was attached for adsorption of lysozyme. The hollow-fibre was characterized by scanning electron microscopy. These dye-carrying hollow-fibres (26.3 mu mol g(-1)) w ere used in the lysozyme adsorption-elution studies. The effect of initial concentration of lysozyme and medium pH on the adsorption efficiency of dye -attached hollow-fibres was studied in a batch system. The non-specific ads orption of lysozyme on the polyamide hollow-fibres was 1.8 mgg(-1). Reactiv e Green HE-4BD attachment significantly increased the lysozyme adsorption u p to 41.1 mgg(-1). Langmuir adsorption model was found to be applicable in interpreting lead adsorption by Reactive Green HE-4BD attached hollow fibre s. Significant amount of the adsorbed lysozyme (up to 95%) was eluted in lh in the elution medium containing 1.0M NaSCN at pH 8.0. In order to determi ne the effects of adsorption conditions on possible conformational changes of lysozyme structure, fluorescence spectrophotometry was employed. We conc luded that polyamide dye-affinity hollow-fibres can be applied for lysozyme adsorption without causing any significant conformational changes. Repeate d adsorption-elution processes showed that these dye-attached hollow-fibres are suitable for lysozyme adsorption. (C) 2001 Society of Chemical Industr y.