Papers by Author: Olga Korostynska

Abstract: Novel method of manufacturing micro sensors arrays for biomedical applications using BioForce NanoeNablerTM is reported. The operation of pH and glucose sensing elements is based on the properties of polymers, which exhibit a change in their electrical characteristics (such as resistance or capacitance) on exposure to solutions with different concentrations of pH or glucose. A sensor for glucose was successfully fabricated using the enzyme glucose oxidase immobilized within the polymer poly (o-phenylenediamine). This sensor was then successfully miniaturized utilizing immobilization for a dry process. The concentrations used for the microsensor were between 1 mM and 6 mM. Samples containing different concentrations of glucose were applied to the sensor while the system was being monitored for variances in either current or conductance. The resulting changes in the electrical characteristics of the sensor monitored in real time were found to be proportional to the different concentrations of glucose applied. Microscaled interdigitated electrodes were used for sensors array, with 48 sensors places on one chip. It is envisaged that findings of this work would form the basis for miniaturised point-of-care diagnostic system.

Abstract: This paper reports on the gamma radiation-induced changes in thin oxide films deposited by thermal vacuum technique. Structures of various oxides thin films, such as In2O3, SiO and TeO2 and their mixtures in different proportions were studied. The influence of gamma radiation on In2O3/SiO films has resulted in significant changes in the microstructure of this film. Some kind of agglomerations with variable sizes in the range 0.5-3 µm has occurred. After a dose of 8160 µSv an evidence of partial crystallisation was observed with X-ray diffraction. Structural changes in TeO2 thin film were explored by means of Raman spectroscopy. After they have been exposed to g- radiation, a strong peak appeared at 448.83 cm-1, indicating further transformation to g-TeO2 modification.