Microcontact imprinting method has been used for various proteins [23], [24], [25], [26] and [27]. BSA (bovine serum albumin) is a protein with the molecular weight of 66.5 kDa and it has many uses in biomedical applications and enzymatic reactions. It is used to prevent adhesion of enzymes during applications [28]. It is a generally used protein reagent in protein assays, like Bradford assay, to measure the concentration of a protein in solution. Furthermore, BSA has a structural homology with HSA (human serum albumin) [29]. Due to this, BSA is frequently studied as a model protein instead of HSA. Moreover, BSA is a commonly used target to analyze when designing new immunochemical

assays. Determination of micro-quantities of BSA is possible with methods like radioimmunoassay (RIA) or enzyme-linked immunosorbent assay Buparlisib cell line (ELISA) [30]. There are also some determinations like FT-IR spectroscopy, polarographic and fluorimetric measurements used for BSA detection [28], [31] and [32]. Some of the methods require a labelled reagent like a radioisotope or enzyme labeled antibody/antigen [30]. Some of them are really expensive and need time-consuming, complex procedures. Low selectivity

and sensitivity is the another drawback IDO inhibitor of these methods [33]. Direct, label-free, fast and sensitive measurement of various analytes with biosensors has attracted considerable interest [34]. Highly sensitive biosensor concepts make it possible to assay biomacromolecules at concentrations below the limit of detection of conventional methods [35]. Capacitive biosensors are the electrochemical sensors that measure changes in the dielectric properties PAK5 when an analyte interacts with a biorecognition element on the sensor surface, causing a decrease in the capacitance [36], [37], [38], [39], [40] and [41]. Capacitive biosensors have been used for the detection of various analytes like antigens, antibodies,

proteins and heavy metal ions [42], [43], [44], [45], [46] and [47]. These types of biosensors have a lot of advantages like inherent rapidity, high sensitivity, simplicity, low cost, easy manipulation and real-time measurement without labeling. In the study reported here, a capacitive biosensor with an automated-flow injection system was used for BSA detection. BSA is most commonly used model protein in the macromolecular imprinting studies. However, to our knowledge, this is the first microcontact-BSA imprinting study for the detection of BSA with the capacitive biosensor. Microcontact imprinting method was applied for the imprinting of BSA onto the pre-modified gold electrode surface. After modification of the gold electrode surface with poly-tyramine and acryloyl chloride, the protein stamp was brought together with a mixture of monomer and cross-linker in contact with the electrode. Thus, the microcontact BSA imprints were introduced to the electrode surface via UV-polymerization.