PMC:4996384 / 17508-19260 JSONTXT

{"target":"https://pubannotation.org/docs/sourcedb/PMC/sourceid/4996384","sourcedb":"PMC","sourceid":"4996384","source_url":"https://www.ncbi.nlm.nih.gov/pmc/4996384","text":"3.3. Adenosine Detection with Split-APT8 Sequence \nIn this section, the detection limit of the sandwich assay with the APT8 splitting sequences were explored. AuNPs were grafted with Split-APT and the biosensor with Split-APT8 sequence. We have already seen that a specific signal (signal ON) is present without adenosine. A series of different adenosine concentrations ranging from 20 to 100 μM in presence of 200 pM of AuNPs were injected on the microarray in the same conditions as the injection of AuNPs alone. The injection of AuNPs was stopped after 24 min without reaching equilibrium. All the experiments present a leveling-off after the arrest of nanoparticles injection. The stability observed for the complexes between AuNPs functionalized with Split-APT and the Split-APT8 probe surface is high enough to avoid any desorption of the AuNPs. The stabilization of the complex formed by the target and the split-aptamers leads to an increased SPRi reflectivity shift for an increasing concentration of adenosine (Figure 4). A detection limit of 50 μM may be deduced from the range of adenosine concentration considered. The selectivity of the biosensor assay was validated by an injection of 100 μM of guanosine (G curve) whose reflectivity shift is comparable to the injection of AuNPs alone.\nFigure 4 A series of different adenosine (A) concentrations have been incubated in presence of Split-APT coated gold nanoparticles. Higher SPRi signals on Split-APT8 spots are observed upon increased concentrations allowing a detection limit of 50 μM. The injection of 100 μM of guanosine (G) does not significantly modify the SPRi signal compared to the injection of gold nanoparticles (AuNPs) alone implying a good selectivity of the biosensor.\n\n3","divisions":[{"label":"Title","span":{"begin":0,"end":50}},{"label":"Figure caption","span":{"begin":1302,"end":1751}}],"tracks":[]}