Layer-by-layer deposition of chitosan derivatives and DNA on gold surfaces for the development of biorecognition layers

M. L. PEDANO; LAURENCE MARTEL; JACQUES DESBRIERES; ERIC DEFRANCQ; PASCAL DUMY; LILIANE COCHE-GUERENTE; PIERRE LABBÉ; JEAN-FRANCOIS LEGRAND; ROBERTO CLEMCZUK; GUSTAVO A. RIVAS

TAYLOR & FRANCIS INC

Año: 2004 vol. 37 p. 2235 - 2235

font size="1" face="AdvPS6F00"> We describe a new supramolecular architecture obtained by deposition of double-stranded deoxyribonucleic acid (dsDNA) and chitosan derivative on a thiolated gold surface. Surface plasmon resonance was used to monitor, in real time, the construction of the supramolecular architecture. Three chitosan derivatives were used, a quaternized N-substituted by three methyl groups in a 40.0mol%, and two others N-substituted with an octyl chain in a 5.0 and 25.0mol%. The multilayer formation depends on the degree of substitution of chitosan as well as on the nature of the substituents. The adsorption of dsDNA is slower than that of chitosan. The best immobilization of dsDNA is obtained by using a quaternized chitosan and dsDNA prepared in 0.050Macetate buffer pH 5.00. The system is stable in buffer solution independently of the nature of the chitosan de