tailieunhanh - Biosensors Emerging Materials and Applications Part 16

Tham khảo tài liệu 'biosensors emerging materials and applications part 16', kỹ thuật - công nghệ, cơ khí - chế tạo máy phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | 592 Biosensors - Emerging Materials and Applications 8S 62 49 38 28 18 Fig. 1. SDS-PAGE electrophoresis gel for highly purified proteins used for this research first lane corresponds to MW markers the second to Lysozyme lys third to Ansocalcin ANCA the fourth and fifth for struthiocalcins 1 and 2 SCA-1 and SCA-2 respectively. ion was investigated. In Figure 2 the electrochemical response in terms of the normalized current measured at V vs SCE Saturated Calomel Electrode anodic barrier with respect to Na2CO3 concentration is shown. Due to the absence of an electrochemical peak to follow the electrochemical response the current related to the anodic barrier which corresponds to the oxidation of carbonate anions was monitored. The protein SCA-1 for instance showed a higher slope and a clear linear response R2 of the current when carbonate concentration in the solution was ranging from 10-3 to 10-2 M and a slope less remarkable for SCA-2. This range was selected to show the response of the biosensor with the isolated proteins from the eggshell but it must be clarified that the biosensor could also give a good response at lower carbonate concentrations or higher sensibility. The comparison of the slope values for these analyzed proteins demonstrated that the biosensor containing SCA-1 was times more sensitive to carbonates than the pure carbon paste electrode. Although these experiments were highly sensitive for detecting protein-carbonate ions interactions when applied to proteins SCA-1 and SCA-2 it was nevertheless a challenge to look for another methodology to detect these interactions chemical recognition using a simple experimental set up. By means of using photon correlation spectroscopy methods like dynamic light scattering DLS can be performed easily using higher amounts of carbonate ions ranging from 10mM to 100mM as those found in the intrauterine fluid in avian Domínguez-Vera et al. 2000 and less amount of protein sample. Many proteins aggregate