Disposable electrochemical DNA-array for PCR amplified detection of hazelnut allergens in foodstuffs.
An electrochemical low-density DNA-array has been designed and implemented to be used in combination with polymerase chain reaction (PCR) in order to investigate the presence of hazelnut major allergens (Cor a 1.04, Cor a 1.03) in foodstuff. Unmodified PCR products were captured at the sensor interface via sandwich hybridization with surface-tethered probes and biotinylated signalling probes. The resulting biotinylated hybrids were coupled with a streptavidin-alkaline phosphatase conjugate and then exposed to a alpha-naphthyl phosphate solution. Differential pulse voltammetry was finally used to detect the alpha-naphthol signal. The detection limits for Cor a 1.03 and Cor a 1.04 were 0.3 and 0.1 nmol L(-1), respectively (R.S.D. 10%). The optimized conditions were used to test several commercially available foodstuffs, claiming to contain or not the targeted nuts. The results were compared with those obtained with classical ELISA tests.
Bettazzi
Francesca
F
Dipartimento di Chimica, Università degli Studi di Firenze, Via della Lastruccia 3, 50019 Sesto Fiorentino (Fi), Italy.
Lucarelli
Fausto
F
Palchetti
Ilaria
I
Berti
Francesca
F
Marrazza
Giovanna
G
Mascini
Marco
M
D000485:Allergens / Q000032:analysis*; D001483:Base Sequence; D031211:Corylus / Q000276:immunology*; D017931:DNA Primers; D004563:Electrochemistry / Q000379:methods*; D004797:Enzyme-Linked Immunosorbent Assay; D020411:Oligonucleotide Array Sequence Analysis; D016133:Polymerase Chain Reaction / Q000379:methods*
D000485:Allergens; D017931:DNA Primers