TY - JOUR
T1 - Comparison of different noble metal-based screen-printed sensors for detection of PIK3CA point-mutations as biomarker for circulating tumor DNA
AU - Thoeny, Vanessa
AU - Melnik, Eva
AU - Maier, Thomas
AU - Kurzhals, Steffen
AU - Derntl, Christian
AU - Pulverer, Walter
AU - Mutinati, Giorgio C.
AU - Asadi, Malahat
AU - Mehrabi, Pooyan
AU - Huetter, Melanie
AU - Schalkhammer, Thomas
AU - Lieberzeit, Peter
AU - Hainberger, Rainer
N1 - Accession Number: WOS:000997601000001
PY - 2023/7/1
Y1 - 2023/7/1
N2 - Screen-printed electrochemical sensors are of particular interest for point-of-care diagnostic applications due to their high sensitivity, short analysis times, and cost-efficient large-scale fabrication. Especially noble metal-based sensors offer the possibility of easy surface modification via self-assembly of thiol-labelled compounds. We examined silver, gold, and palladium as electrode materials regarding their suitability for highly specific and sensitive DNA detection with a chronoamperometric enzyme-amplified electrochemical assay. Modification with either gold nanoparticles or silver-coated microbeads was tested as a possibility to improve the performance of the electrochemical sensors. The sensors were characterized regarding surface topography, sensitivity towards the redox-active substrate TMB, efficiency of capture probe immobilization, as well as mutation specificity. The highest sensitivity for oxidized TMB was observed for gold sensors that yielded a limit of detection of 2.1 µM, while no improvement in sensitivity was observed for sensors modified with gold nanoparticles or silver-coated microbeads. DNA probe immobilization and multiplexed target DNA detection was successful with all tested electrode materials. However, modification with silver-coated microbeads led to both reduced probe immobilization efficiency and hybridization specificity. Gold nanoparticle modification of both silver and of gold sensors induced a highly porous sensor surface after sintering, which increases the surface area of the electrodes. The gold nanoparticle modified sensors showed particularly appreciable results in terms of improved hybridization specificity, as demonstrated by successful multiplexed detection of three PIK3CA point-mutations (H1047R, E545K, and E542K). Average discrimination factors D of 2.7 and 2.1 were obtained for gold and silver sensors modified with one layer of gold nanoparticles, respectively.
AB - Screen-printed electrochemical sensors are of particular interest for point-of-care diagnostic applications due to their high sensitivity, short analysis times, and cost-efficient large-scale fabrication. Especially noble metal-based sensors offer the possibility of easy surface modification via self-assembly of thiol-labelled compounds. We examined silver, gold, and palladium as electrode materials regarding their suitability for highly specific and sensitive DNA detection with a chronoamperometric enzyme-amplified electrochemical assay. Modification with either gold nanoparticles or silver-coated microbeads was tested as a possibility to improve the performance of the electrochemical sensors. The sensors were characterized regarding surface topography, sensitivity towards the redox-active substrate TMB, efficiency of capture probe immobilization, as well as mutation specificity. The highest sensitivity for oxidized TMB was observed for gold sensors that yielded a limit of detection of 2.1 µM, while no improvement in sensitivity was observed for sensors modified with gold nanoparticles or silver-coated microbeads. DNA probe immobilization and multiplexed target DNA detection was successful with all tested electrode materials. However, modification with silver-coated microbeads led to both reduced probe immobilization efficiency and hybridization specificity. Gold nanoparticle modification of both silver and of gold sensors induced a highly porous sensor surface after sintering, which increases the surface area of the electrodes. The gold nanoparticle modified sensors showed particularly appreciable results in terms of improved hybridization specificity, as demonstrated by successful multiplexed detection of three PIK3CA point-mutations (H1047R, E545K, and E542K). Average discrimination factors D of 2.7 and 2.1 were obtained for gold and silver sensors modified with one layer of gold nanoparticles, respectively.
KW - DNA-biosensor
KW - Gold nanoparticle modified electrodes
KW - Multiplexed electrochemical sensor
KW - Noble metal screen-printed electrodes
KW - Point-mutation detection
UR - http://www.scopus.com/inward/record.url?scp=85154587570&partnerID=8YFLogxK
U2 - 10.1016/j.electacta.2023.142336
DO - 10.1016/j.electacta.2023.142336
M3 - Article
AN - SCOPUS:85154587570
SN - 0013-4686
VL - 455
JO - Electrochimica Acta
JF - Electrochimica Acta
M1 - 142336
ER -
