Dependence of yield of nuclear track-biosensors on track radius and analyte concentration

NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS

卷:420

Article

Garcia-Arellano, H.¹  Munoz H, G.²  Fink, D.^2,3  Vacik, J.³  Hnatowicz, V.³  Alfonta, L.^4,5  Kiv, A.⁶ 

[1] Univ Autonoma Metropolitan Lerma, Div Ciencias Biol & Salud, Dept Ciencias Ambientales, Av Garzas 10, Municipio De Lerma 52005, Estado De Mexic, Mexico

[2] Univ Autonoma Metropolitana Iztapalapa, Dept Fis, POB 55-534, Mexico City 09340, DF, Mexico

[3] ASCR, Nucl Phys Inst, Rez 25068, Czech Republic

[4] Ben Gurion Univ Negev, Dept Life Sci, POB 653, IL-84105 Beer Sheva, Israel

[5] Ben Gurion Univ Negev, Ilse Katz Inst Nanoscale Sci & Technol, POB 653, IL-84105 Beer Sheva, Israel

[6] Ben Gurion Univ Negev, POB 653, IL-84105 Beer Sheva, Israel

关键词: Biosensor;    Ion track;    Etching;    Enzyme;    Nanofluidics;   

DOI  :  10.1016/j.nimb.2018.02.010

来源: Elsevier

【 摘 要 】

In swift heavy ion track-based polymeric biosensor foils with incorporated enzymes one exploits the correlation between the analyte concentration and the sensor current, via the enrichment of charged enzymatic reaction products in the track's confinement. Here we study the influence of the etched track radius on the biosensor's efficiency. These sensors are analyte-specific only if both the track radii and the analyte concentration exceed certain threshold values of similar to 15 nm and similar to 10(-6) M (for glucose sensing), respectively. Below these limits the sensor signal stems un-specifically from any charge carrier. In its proper working regime, the inner track walls are smoothly covered by enzymes and the efficiency is practically radius independent. Theory shows that the measured current should be slightly sub-proportional to the analyte concentration; the measurements roughly reconfirm this. Narrower tracks (similar to 5-15 run radius) with reduced enzyme coverage lead to decreasing efficiency. Tiny signals visible when the tracks are etched to effective radii between 0 and similar to 5 nm are tentatively ascribed to enzymes bonded to surface-near nano-cracks in the polymer foil, resulting from its degradation due to aging, rather than to the tracks. Precondition for this study was the accurate determination of the etched track radii, which is possible only by a nanofluidic approach. This holds to some extent even for enzyme-covered tracks, though in this case most of the wall charges are compensated by enzyme bonding.

【 授权许可】

Free