Akademik Veri Yönetim Sistemi
Tezin Türü: Yüksek Lisans
Tezin Yürütüldüğü Kurum: Marmara Üniversitesi, Mühendislik Fakültesi, Elektrik ve Elektronik Mühendisliği Bölümü, Türkiye
Tezin Dili: İngilizce
Öğrenci: ETKİ GÜR
Danışman: Alper Şişman
Özet:
Surface acoustic wave (SAW) devices with interdigitated microelectrodes serving as interdigital transducers (IDTs) are commonly used in the information technology industry as electronic filters in delay line or resonator configurations[1] SAW sensors response a certain phsical changes, e.g humidity[2], mass[3], temperature[4] and particularly the chemical or biochemical binding event on surfaces that affects the mass on the delay line. In our study, we will focus on biochemical bindings comes from biomarkers that can be used for diagnosis. Biomarkers are biological indicators of diseases. Biomarkers can be measured either in vivo or in vitro ,namely, by biomedical imaging or by laboratory methods [5]. Some kind of proteins can be potential biomarker to detect a number of cancer types. Interaction of protein antigen with antibody is a biochemical reaction cause precipitation on the surface.The main principle on the procedure of the quantifiying protein level, using the process that is sensitive to the desired protein [6]. For example, in ELISA tests, the microarray surfaces are directly spotted with the antigen that is specific to the determined protein. Adsorbtion of protein to the surface will be done by the adhesion of the protein with antibody then the enzyme that can adsorb to that structure is released to the surrounding environment. Afterwards, the substrate which reacts with that enzyme is added. The concentration of the output of that reaction is ascertained with spectrofotometric or spectroflourometric methods. In our method, the surface will be immobilized with the antibodys that can be affected by the desired protein. If that surface is a delay line of a SAW sensor, that precipitation gives information about the concentration of the soluble protein. Mass on the delay line of SAW Sensor that is the output of precipitation reaction leads the phase shifts of the propagating wave on that line. The amount of phase shift increases in direct proportion to the precipitation. A biosensor has three main parts; firstly the selective part that has an antibody layer sensitive to the target protein, secondly the quntifying part that converts the protein-antibody interaction to a measurable signal and finally signal detection. A readout electronic circuit measures the signal effectively. That circuit contains an amplifier circuit which increases the amplitude of the sensor output to the sufficient voltage level, the converter of given signal from analog sensor output to the digital microprocessor input, a microprocessor that applies the mathematical transactions to the digitalized signal then calculates the phase difference. When it is taken into consideration that there will be the noise from that circuits and additional phase shifts from the intermediate circuits, it is necessary that a study in this area should be carried out.