The development analytical assay for determination of Association constants of alkaloids to amyloid ß peptide determined by electrochemical impedance spectroscopy
Amyloid β(1-40) peptide was immobilized on Au-colloid modified gold electrode and an electrochemical impedance spectroscopy (EIS) system was elaborated for determining of the association constants, Ka, between alkaloids of a known ability to cross the blood-brain barrier and the peptide. The method is sensitive, reproducible and consumes only very little amounts of interacting species. The ligand-Aβ(1-40) binding data, obtained with EIS method may be of relevance for design of anti-Alzheimer’s disease therapeutic and/or prophylactic agents.
New assays procedures for use in modern medicinal chemistry, like electrochemical impedance spectroscopy (EIS), allow for fast and reliable testing of properties of relevance for bioactivity of various substances. Using EIS it seems worthwhile to screen large numbers of potential drug candidates.
The development of analytical tool based on Surface Plasmon Resonance for screening the influence of naturally occurring compounds on the aggregation of amyloid-β peptide (Aβ40)
The gold discs used for surface plasmon resonance (SPR) measurements, modified with thio – aliphatic acid, were used for covalent attaching of Aβ40 probe by creation of amide bond in the presence of EDC/NHS and used for exploring Aβ40 aggregation process in the presence of selected alkaloids. The presented results showed that developed SPR spectroscopy-based aggregation assay allows to monitor the Aβ40 aggregation phenomenon in the real-time, without using any chemical markers influencing the process. This approach could be applied as a tool for screening candidates as a potent anti-amyloidogenic drug and find the relationship between their chemical structures and anti- Aβ40 peptide aggregation activity.
The stable and oriented immobilization of his-tagged Rio1 protein on the surface of redox active monolayer incorporated with iminodiacetic acid –Cu(II) complex
The gold electrode modified with mixed N-acetylcysteamine and iminodiacetic acid was suitable for efficient chelating of Cu(II) ions. The electroactive monolayer was applied for oriented and stable immobilization of rHis6-Rio1 protein through covalent bonds formed between Cu(II) centres and imidazole nitrogen atoms from histidine tag. The obtained biosensor was successfully applied for electrochemical screening of the interactions between rHis6-Rio1 protein and selected inhibitors. The proposed analytical tool might be used for electrochemical sensing of other biological systems involving his-tagged proteins.