A biofunctional polymeric coating for microcantilever molecular recognition.
An innovative route to activate silicon microcantilevers (MCs) for label free molecular recognition is presented. The method consists in coating the underivatized MCs with a functional ter-polymer based on N,N-dimethylacrylamide (DMA) bearing N-acryloyloxysuccinimide (NAS) and 3-(trimethoxysilyl)propyl-methacrylate (MAPS), two functional monomers that confer to the polymer the ability to react with nucleophilic species on biomolecules and with glass silanols, respectively. The polymer was deposited onto MCs by dip coating. Polymer coated MCs were tested in both static and dynamic modes of actuation, featuring detection of DNA hybridization as well as protein/protein interaction. In the dynamic experiments, focused on protein detection, the MCs showed an average mass responsivity of 0.4 Hz/pg for the first resonant mode and of 2.5 Hz/pg for the second resonant mode. The results of the static experiments, dedicated to DNA hybridization detection, allowed for direct estimation of the DNA duplex formation energetics, which resulted fully consistent with the nominal expected values. These results, together with easiness and cheapness, high versatility, and excellent stability of the recognition signal, make the presented route a reliable alternative to standard SAM functionalization (for microcantilevers (MCs) and for micro-electro-mechanical systems (MEMS) in general).
Oliviero
Giulio
G
Chemistry for Technologies Laboratory, University of Brescia, Brescia, Italy. giulio.oliviero@ing.unibs.it
Bergese
Paolo
P
Canavese
Giancarlo
G
Chiari
Marcella
M
Colombi
Paolo
P
Cretich
Marina
M
Damin
Francesco
F
Fiorilli
Sonia
S
Marasso
Simone L
SL
Ricciardi
Carlo
C
Rivolo
Paola
P
Depero
Laura E
LE
D000178:Acrylamides / Q000138:chemical synthesis; D000179:Acrylates / Q000138:chemical synthesis; D015374:Biosensing Techniques / Q000295:instrumentation / Q000379:methods*; D004247:DNA / Q000378:metabolism; D008689:Methacrylates / Q000138:chemical synthesis; D009693:Nucleic Acid Hybridization; D017646:Organosilicon Compounds / Q000138:chemical synthesis; D011108:Polymers / Q000138:chemical synthesis* / Q000737:chemistry / Q000378:metabolism; D011506:Proteins / Q000378:metabolism; D013388:Succinimides / Q000138:chemical synthesis
D000178:Acrylamides; D000179:Acrylates; D008689:Methacrylates; D017646:Organosilicon Compounds; D011108:Polymers; D011506:Proteins; D013388:Succinimides; D004247:DNA; C099046:N,N-dimethylacrylamide; C505504:3-(trimethoxysilyl)propyl methacrylate