title: Porous silicon-based optical microsensor for the detection of L-glutamine.
abstract: The molecular binding between the glutamine-binding protein (GlnBP) from Escherichia coli and L-glutamine (Gln) is optically transduced by means of a biosensor based on porous silicon nano-technology. The sensor operates by the measurement of the interferometric fringes in the reflectivity spectrum of a porous silicon Fabry-Perot layer. The binding event is revealed as a shift in wavelength of the fringes. Due to the hydrophobic interaction with the Si-H terminated surface of the porous silicon, the GlnBP protein, which acts as a molecular probe for Gln, penetrates and links into the pores of the porous silicon matrix. We can thus avoid any preliminary functionalization process of the porous layer surface, which is also prevented from oxidation, at least for few cycles of wet measurements. The binding of Gln to GlnBP has also been investigated at different concentration of GlnBP.
authors.affiliation: Institute for Microelectronics and Microsystems, Department of Naples, National Council of Research, Italy. luca.destefano@na.imm.cnr.it
authors.forename: Luca
authors.initials: L
authors.lastname: De Stefano
authors.forename: Lucia
authors.initials: L
authors.lastname: Rotiroti
authors.forename: Ivo
authors.initials: I
authors.lastname: Rendina
authors.forename: Luigi
authors.initials: L
authors.lastname: Moretti
authors.forename: Viviana
authors.initials: V
authors.lastname: Scognamiglio
authors.forename: Mosè
authors.initials: M
authors.lastname: Rossi
authors.forename: Sabato
authors.initials: S
authors.lastname: D'Auria
mesh_terms: D015374:Biosensing Techniques / Q000295:instrumentation* / Q000379:methods; D004867:Equipment Design; D019544:Equipment Failure Analysis; D005336:Fiber Optic Technology / Q000295:instrumentation*; D005973:Glutamine / Q000032:analysis*; D007368:Interferometry / Q000295:instrumentation* / Q000379:methods; D016062:Porosity; D012031:Refractometry / Q000295:instrumentation* / Q000379:methods; D012825:Silicon / Q000737:chemistry*; D013057:Spectrum Analysis / Q000295:instrumentation*
chemical_list: D005973:Glutamine; D012825:Silicon