Semiquantitative study of the EDC/NHS activation of acid terminal groups at modified porous silicon surfaces.
Infrared spectroscopy is used to investigate the transformation of carboxyl-terminated alkyl chains immobilized on a surface into succinimidyl ester-terminated chains by reaction with an aqueous solution of N-ethyl-N'-(3-(dimethylamino)propyl)carbodiimide (EDC) and N-hydroxysuccinimide (NHS). The acid chains are covalently grafted at the surface of hydrogenated porous silicon whose large specific surface area allows for assessing the activation yield in a semiquantitative way by infrared (IR) spectroscopy and detecting trace amounts of surface products and/or reaction products of small IR cross section. In this way, we rationalize the different reaction paths and optimize the reaction conditions to obtain as pure as possible succinimidyl ester-terminated surfaces. A diagram mapping the surface composition after activation was constructed by systematically varying the solution composition. Results are accounted for by NHS surface adsorption and a kinetic competition between the various EDC-induced surface reactions.
Sam
S
S
Physique de la Matière Condensée, Ecole Polytechnique, CNRS, 91128 Palaiseau, France.
Touahir
L
L
Salvador Andresa
J
J
Allongue
P
P
Chazalviel
J-N
JN
Gouget-Laemmel
A C
AC
Henry de Villeneuve
C
C
Moraillon
A
A
Ozanam
F
F
Gabouze
N
N
Djebbar
S
S
D005022:Ethyldimethylaminopropyl Carbodiimide / Q000737:chemistry*; D008962:Models, Theoretical; D016062:Porosity; D012825:Silicon / Q000737:chemistry*; D013055:Spectrophotometry, Infrared; D017550:Spectroscopy, Fourier Transform Infrared; D013388:Succinimides / Q000737:chemistry*; D014476:Undecylenic Acids / Q000737:chemistry
D013388:Succinimides; D014476:Undecylenic Acids; C001426:N-hydroxysuccinimide; D005022:Ethyldimethylaminopropyl Carbodiimide; D012825:Silicon