Nanowire SOI biosensors are used to detect the Ebola virus VP40 protein by identifying its immune complexes with specific monoclonal antibodies (MCAs). It

The detection of influenza A virions with a nanoribbon detector (NR detector) has been demonstrated. Chips for the detector have been fabricated based on silicon-on-insulator nanoribbon structures (SOI nanoribbon chip), using a complementary metal-oxide-semiconductor (CMOS)-compatible technology—by means of gas-phase etching and standard optical photolithography. The surface of the SOI nanoribbon chip contains a matrix of 10 nanoribbon (NR) sensor elements. SOI nanoribbon chips of n-type conductance have been used for this study. For biospecific detection of target particles, antibodies against influenza virus have been covalently immobilized onto NRs. Influenza A virus detection was performed by real-time registration of the source-drain current through the NRs. The detection of the target viral particles was carried out in buffer solutions at the target particles concentration within the range from 10⁷ to 10³ viral particles per milliliter (VP/mL). The lowest detectable concentration of the target viral particles was 6 × 10⁻¹⁶ M (corresponding to 10⁴ VP/mL). The use of solutions containing ~10⁹ to 10¹⁰ VP/mL resulted in saturation of the sensor surface with the target virions. In the saturation mode, detection was impossible.

Hemorheological disorders in structural and functional parameters of erythrocytes are involved in the pathological process in type 2 diabetes mellitus (DM). Aim: to investigate the feasibility of differential diagnosis of the degrees of rheological disturbances in patients with type 2 DM by dielectrophoresis of erythrocytes. Methods: 62 subjects (58.7 ± 1.6 years) with type 2 DM diagnosed according to the criteria of the ADA were subdivided into two groups: medium (n = 47) and high (n = 15) risk of microcirculatory disturbances (EASD, 2013). Electric and viscoelastic parameters of erythrocytes were determined by dielectrophoresis using an electric optical system of cell detection. Results: the progression of rheological disturbances in the patients with type 2 DM was accompanied by significant decreases in deformation amplitude; dipole moment; polarizability; and membrane capacity; and increases in conductivity, viscosity, rigidity, hemolysis, and formation of aggregates (p < 0.05). Combined use of the parameters increased sensitivity (97.8%) and specificity (86.7%) for diagnosis of rheological disturbances in type 2 DM. Conclusion: the proposed experimental approach possesses low invasiveness, high productivity, shorter duration, vividness of the results. The method allows to evaluate not only local (renal and ocular) but also systemic status of microcirculation using more than 20 parameters of erythrocytes.

Issues concerning the detection of biomolecular targets by biosensors based on silicon nanowire field-effect transistors are discussed. We list and discuss steps in the surface preparation of silicon nanowires that lead to the efficient, highly sensitive, and selective detection of various analytes. The procedures for cleaning and activation of the surface of the silicon nanowires are addressed. Wet and dry methods for surface cleaning as well as surface-modification strategies applicable to transducers of biosensors are described. Surface modification by silane derivatives (i.e., silanization) and linker attachment is paid particular attention. The causes underlying the undesirable screening effect affecting a nanowire surface upon analyte detection in solutions are provided. The key requirements and strategies relevant to different steps in the preparation of biosensor surfaces that lead to improvement in their performance are mentioned.