| Title |
Polipirolu modifikuotų biologiniuose jutikliuose naudojamų sistemų tyrimas fluorescencijos metodais / |
| Translation of Title |
Study of polypyrrole based biosensing systems by fluorescence methods. |
| Authors |
Samukaitė-Bubnienė, Urtė |
| Full Text |
|
| Pages |
32 |
| Keywords [eng] |
Biosensing system ; fluorescence ; enzyme ; conductive polymer. |
| Abstract [eng] |
In this work glucose oxidase (GOx) was self-encapsulated within ‚enzymaticaly‘ formed polymer - polypyrrole. This process was investigated by the fluorescence methods. During the fluorescence measurements it was determined that the enzyme glucose oxidase is immobilized within the polypyrrole matrix. Formed Ppy matrix slowed down the dissociation of cofactor – flavin adenine dinucleotide (FAD) – from the GOx. The conducting polymer polypyrrole was also applied as a matrix for the immobilization of BLV surface protein gp51, which was applied as biological recognition system for the determination of antibodies against protein gp51 (anti- gp51). Ppy acted as a fluorescence quencher and increased the selectivity of this immunosensing system because Ppy quenched the fluorescence of non-specifically absorbed materials. The influence of gold nanoparticles (AuNPs) on polypyrrole-based biosensing systems was analysed. Some aspects of absorbance of nanoparticles onto surface was determined. The electrophoretic mobilities and electrokinetic charge of particles were quantitatively evaluated in a broad range of pH and ionic strength. Additionally, the maximum coverage of particle monolayers, which monotonically increased with ionic strength, was determined by SEM. The obtained data were in agreement with theoretical predictions derived from the random sequential adsorption (RSA) model. It was also confirmed that by varying the bulk suspension concentration and ionic strength one can prepare homogeneous gold particle monolayers of controlled coverage. The study of system consisting of glucose oxidase, polypyrrole and gold nanoparticles was conducted by time-resolved fluorescence. Gold nanoparticle surface was negatively charged in a broad range of pH and ionic strength and was suitable for the formation of polypyrrole on their surface. |
| Dissertation Institution |
Vilniaus universitetas. |
| Type |
Summaries of doctoral thesis |
| Language |
Lithuanian |
| Publication date |
2015 |
