Self-tuning interfacial architecture for Estradiol detection by surface plasmon resonance biosensor.

This study reports the operation principles for reusable SPR biosensors utilizing nanoscale-specific electrostatic levitation phenomena in their sensitive layer design. Functional macromolecular building blocks localized near the "charged" surface by a variety of weak electrostatic interactions create a flexible and structurally variable architecture. A proof-of-concept is demonstrated by an immunospecific detection of 17β-Estradiol (E2) following the competitive inhibition format.

Diagnosis of Epstein-Barr virus infection in clinical serum samples by an SPR biosensor assay.

Label-free affinity biosensors offer a promising platform for the development of a new generation of medical diagnostic technologies. Nevertheless, when such sensors are used in complex biological media, adsorption of non-targeted medium components prevents the specific detection of the analyte. In this work, we introduce for the first time a biosensor assay based on surface plasmon resonance (SPR) capable of diagnosing different stages of Epstein-Barr virus (EBV) infections in clinical serum samples.

A simple SPR-based method for the quantification of the effect of potential virus inhibitors.

Here, we describe a highly sensitive method that allows for the correct quantification of inhibition effect with a higher degree of accuracy directly at the molecular level. The protocol involves two stages, namely serological virus titration in comparison with the same procedure for virus-effector mixture. Owing to the robustness of the analysis this assay can be performed on crude cellular and plant extracts, and therefore it may be suitable for the routine analysis of clinical samples, or in the field.

[Immobilization of the glutathione by the complementary coordination binding].

A simple method for immobilization of biologically imporant molecules with many functional fragments by selective binding of their thiogroups with the surface caroxyl groups by cadmium ions was proposed. Biofunctional properties of these structures were studied by surface plasmon resonance method on the model of the glutathione (GSH), which was immobilized by means of mixed (a:b form 1:100 o 1:700) thiol monolayers with terminal groups of the methyl/hydroxyl (b) and carboxyl (a) type. The maintenance of the biofunctional conformation ofglutathione-S-transferase (GST) after its interaction with GSH was checked by the use of specific anti-GST antibodies.

The effect of low pH on the glycitein-BSA conjugate interaction with specific antiserum: competitive inhibition study using surface plasmon resonance technique.

Competitive inhibition serological assay for detection of the phytoestrogen glycitein (Glyc) was developed using surface plasmon resonance (SPR) technique with protein conjugates and polyclonal antibodies initially designed for the enzyme-linked immunosorbent assays (ELISA). The efficiency of the approach to the quantification of the soy isoflavone glycitein in water was investigated using the competitive reaction of analyte (free Glyc)and immobilized Glyc-BSA-conjugate with polyclonal antibodies. It was shown that the efficiency to detect Glyc drastically depends on the pH level of the probe solution.