(267f) Adsorption and Desorption of Lysozyme on Thermosensitive Nano-Sized Magnetic Particles and Its Conformational Changes

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and desorption of lysozyme on thermosensitive nano magnetic particles and its conformational changes were studied in this work. Poly (N-isopropylacrylamide) (PNIPAM) coated nano magnetic particles were used as adsorbents. Adsorption of lysozyme on these PNIPAM coated particles was carried out at different temperatures and pH values. It was observed that maximum amount of lysozyme was adsorbed at pH 11 which is the isoelectric point of lysozyme; and at a temperature (40oC) higher than the lower critical solution temperature of the polymer (32oC). The adsorption is believed to be due to the hydrophobic effect of the polymer. Desorption of lysozyme from nano magnetic particles was achieved using NaH2PO4 (pH 4.0) and NaSCN (pH 6.0) as desorbents. However, higher desorption efficiencies was achieved when prior adsorption was done at lower temperature. The conformational change of the lysozyme desorbed by NaH2PO4 was small, while the lysozyme desorbed by NaSCN underwent significant conformational change as measured by the intrinsic fluorescence. 81.42 % activity was retained in the desorbed enzyme for desorption by NaH2PO4.

Keywords: Nano-magnetic particles, N-isopropylacrylamide; lysozyme; hydrophobic; conformational change; enzyme activity.

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Adsorption and Desorption of lysozyme on thermosensitive nano-sized magnetic particles and its conformational changes

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and Desorption of lysozyme on thermosensitive nano-sized magnetic particles and its conformational changes

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Abstract for APCChE conference

g0203689@nus.edu.sg

Nabila Shamim

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