ao8b03131_si_001.pdf (713.43 kB)
Aptasensor for Quantifying Pancreatic Polypeptide
journal contribution
posted on 2019-02-08, 19:36 authored by Ahmed
S. M. Ali, Medhat S. El-Halawany, Sherif Abdelaziz Ibrahim, Olga Plückthun, Ahmed S. G. Khalil, Günter MayerHerein, a simple colorimetric aptasensor based on unmodified gold nanoparticles (AuNPs) has been
developed for quantifying pancreatic polypeptide (PP), a peptide hormone
associated with nonfunctional neuroendocrine pancreatic tumor (NF-PNET).
First, several PP-specific aptamers have been screened by systematic
evolution of ligands by exponential enrichment. The generated aptamers
showed specificity and affinity higher than those reported so far.
The sensing platform was constructed based on the optical properties
of AuNPs as well as the adsorption of single-stranded DNA aptamers.
The high sensitivity of the developed aptasensor was achieved by optimizing
the sensing conditions, including salt tolerance, time of reaction,
and optimal aptamer concentration. The developed aptasensor showed
a wide linear dynamic range (1–60 nM) with a limit of detection
of 521 pM. Furthermore, the performance of the aptasensor was evaluated
for the detection of PP in human serum and showed recovery values
ranging between 92.4 and 93.9%. Therefore, the presented colorimetric
aptasensor has a great potential in the diagnosis of NF-pNETs.