TY  - JOUR
A1  - Halamek, Jan
A1  - Makower, Alexander
A1  - Knösche, Kristina
A1  - Skladal, Petr
A1  - Scheller, Frieder W.
T1  - Piezoelectric affinity sensors for cocaine and cholinesterase inhibitors
N2  - We report here the development of piezoelectric affinity sensors for cocaine and cholinesterase inhibitors based on the formation of affinity complexes between an immobilized cocaine derivative and an anti-cocaine antibody or cholinesterase. For both binding reactions benzoylecgonine-1,8-diamino-3,4-dioxaoctane (BZE-DADOO) was immobilized on the surface of the sensor. For immobilization. pre-conjugated BZE-DADOO with 11-mercaptomonoundecanoic acid (MUA) via 2- (5-norbornen-2,3-dicarboximide)-1,1,3,3-tetramethyluronium-tetrafluoro borate (TNTU) allowed the formation of a chemisorbed monolayer on the piezosensor surface. The detection of cocaine was based oil a competitive assay. The change of frequency measured after 300 s of the binding reaction was used as the signal. The maximum binding of the antibody resulted in a frequency decrease of 35 Hz (with an imprecision 3%, n = 3) while the presence of 100 pmol I-1 cocaine decreased the binding by 11%. The limit of detection was consequently below 100 pmol I-1 for cocaine. The total time of one analysis was 15 min. This BZE-DADOO-modified sensor was adapted for the detection of organophosphates. BZE-DADOO - a competitive inhibitor - served as binding element for cholinesterase in a competitive assay. (C) 2004 Elsevier B.V. All rights reserved
Y1  - 2005
ER  - 
TY  - JOUR
A1  - Knösche, Kristina
A1  - Halámek, Jan
A1  - Makower, Alexander
A1  - Fournier, Didier
A1  - Scheller, Frieder W.
T1  - Molecular recognition of cocaine by acetylcholinesterases for affinity purification and bio-sensing
Y1  - 2003
ER  -