Impedimetric aptasensor for tobramycin detection in human serum.
An RNA aptamer is proposed as a recognition element for the detection of tobramycin in human serum. A displacement assay was developed using faradaic-electrochemical impedance spectroscopy (F-EIS) as a detection technique. Two modified aptamers, a partially (ATA) and a fully O-methylated aptamer (FATA) were evaluated and compared. The affinity constant, K(D), for both aptamers was estimated by F-EIS resulting virtually identical within the experimental error. The selectivity towards other aminoglycosides was also studied. The analytical characteristics were evaluated in aqueous solution using both aptamers and FATA was selected for human serum experiments. Using a 1:0.5 dilution of the serum, a linear range between 3 μM and 72.1 μM was obtained, which included the therapeutic range of the antibiotic.
Dpto. Química Física y Analítica, Universidad de Oviedo, C/ Julián Clavería 8, 33006 Oviedo, Spain.
Eva
E
González-Fernández
Noemí
N
de-los-Santos-Álvarez
María Jesús
MJ
Lobo-Castañón
Arturo José
AJ
Miranda-Ordieres
Paulino
P
Tuñón-Blanco
D052157:Aptamers, Nucleotide / Q000737:chemistry*; D015374:Biosensing Techniques / Q000295:instrumentation*; D001774:Blood Chemical Analysis / Q000295:instrumentation*; D003217:Conductometry / Q000295:instrumentation*; D058266:Dielectric Spectroscopy / Q000295:instrumentation*; D004867:Equipment Design; D019544:Equipment Failure Analysis; D006801:Humans; D014031:Tobramycin / Q000097:blood*
D052157:Aptamers, Nucleotide; D014031:Tobramycin