title: Fluorescence polarization biosensor based on an aptamer enzymatic cleavage protection strategy.
abstract: A novel fluorescence polarization (FP) aptasensing platform based on target-induced aptamer enzymatic cleavage protection is reported. The method relies on the FP analysis of the phosphodiesterase I mediated size variation of a dye-labeled aptamer. The tyrosinamide/antityrosinamide DNA aptamer couple was firstly tested as a model system to establish the proof-of-concept. In the absence of the target, the labeled aptamer was enzymatically cleaved into small DNA fragments, leading to a low FP signal. Upon tyrosinamide binding, the DNA substrate was partially protected against the enzymatic attack, leading to an increase in the fluorescence anisotropy response as a result of the higher average molecular volume of the weakly digested probe. The method was subsequently applied to two other systems, i.e., for the detection of ochratoxin A and adenosine. Such an approach was found to combine simplicity and general applicability features.
authors: Département de Pharmacochimie Moléculaire UMR 5063 CNRS, ICMG FR 2607, Université de Grenoble, Grenoble, France.
authors: Anthony
authors: A
authors: Kidd
authors: Valérie
authors: V
authors: Guieu
authors: Sandrine
authors: S
authors: Perrier
authors: Corinne
authors: C
authors: Ravelet
authors: Eric
authors: E
authors: Peyrin
mesh_terms: D000241:Adenosine / Q000032:analysis; D052157:Aptamers, Nucleotide / Q000737:chemistry*; D015374:Biosensing Techniques / Q000295:instrumentation / Q000379:methods*; D005454:Fluorescence Polarization / Q000295:instrumentation / Q000379:methods*; D005456:Fluorescent Dyes / Q000737:chemistry; D009793:Ochratoxins / Q000032:analysis; D043264:Phosphodiesterase I / Q000737:chemistry*
chemical_list: D052157:Aptamers, Nucleotide; D005456:Fluorescent Dyes; D009793:Ochratoxins; C025589:ochratoxin A; D043264:Phosphodiesterase I; D000241:Adenosine