Preparation and characterization of magnetic levan particles as matrix for trypsin immobilization

JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS

卷:324

Article

Maciel, J. C.²  Andrad, P. L.³  Neri, D. F. M.¹  Carvalho, L. B., Jr.⁴  Cardoso, C. A.⁵  Calazans, G. M. T.⁶  Albino Aguiar, J.⁷  Silva, M. P. C.⁴ 

[1] Univ Fed Vale Sao Francisco, BR-56304205 Petrolina, PE, Brazil

[2] Univ Fed Pernambuco, Grama PosGrad Ciencias Biol, BR-50670901 Recife, PE, Brazil

[3] Univ Fed Pernambuco, Programa PosGrad Ciencia Mat, BR-50679901 Recife, PE, Brazil

[4] Univ Fed Pernambuco, Dept Bioquim, BR-50679901 Recife, PE, Brazil

[5] Univ Fed Sao Carlos, Dept Fis, BR-13565905 Sao Carlos, PE, Brazil

[6] Univ Fed Pernambuco, Dept Antibiot, BR-50670901 Recife, PE, Brazil

[7] Univ Fed Pernambuco, Dept Fis, BR-50679901 Recife, PE, Brazil

关键词: Levan;    Magnetic particle;    Trypsin immobilization;   

DOI  :  10.1016/j.jmmm.2011.11.017

来源: Elsevier

【 摘 要 】

Magnetic levan was synthesized by co-precipitating D-fructofuranosyl homopolysaccharide with a solution containing Fe2+ and Fe3+ in alkaline conditions at 100 degrees C. The magnetic levan particles were characterized by scanning electron microscopy (SEM), magnetization measurements, X-ray diffractometry (XRD) and infrared spectroscopy (IR). Afterwards, magnetic levan particles were functionalized by NaIO4 oxidation and used as matrices for trypsin covalent immobilization. Magnetite and magnetic levan particles were both heterogeneous in shape and levan-magnetite presented bigger sizes compared to magnetite according to SEM images. Magnetic levan particles exhibited a magnetization 10 times lower as compared to magnetite ones, probably, due to the coating layer. XRD diffractogram showed that magnetite is the dominant phase in the magnetic levan. Infrared spectroscopy showed characteristics absorption bands of levan and magnetite (O-H, C-O-C and Fe-O bonds). The immobilized trypsin derivative was reused 10 times and lost 16% of its initial specific activity only. Therefore, these magnetic levan particles can be proposed as an alternative matrices for enzyme immobilization. (C) 2011 Elsevier B.V. All rights reserved.

【 授权许可】

Free