Using Algan / Gan For Biosensing Applications

The purpose of this experiment was to investigate the effect of protein adsorption and thrombus formation on a pH sensor in regards to its function and accuracy. [2] Different solutions of pH were first measured with a clean, calibrated sensor. Then measured again after the same sensor was exposed to a blood solution.

All the data was fitted satisfactorily using the equivalent circuit shown in Fig. 7. Where, Rs, CPE1 and R1 represent solution resistance, a constant- phase element corresponding to the double layer capacitance and the charge transfer resistance, respectively. CPE2 and R2 were added to account for the electrical elements of the outer layer. The following formula expressed the electrode impedance, Z, as follow:

The purpose of this experiment was to investigate the effect of protein adsorption and thrombus formation on a pH sensor in regards to its function and accuracy. [2] Different solutions of pH were first measured with a clean, calibrated sensor. Then measured again after the same sensor was exposed to a blood solution.

As demonstrated in the above diagram, the channel extends from extracellular area through the cell membrane and narrows at the charge selective filter as it

2. What happened to the rate of facilitated diffusion when the number of carrier proteins was increased?

"The calcium-sensing- gate mechanism discovered here is an entirely novel concept with potential to shift our general understanding of ion channel gating, cardiac arrhythmogenesis, and the treatment of calcium-triggered arrhythmias”

Whenever a monolayer is attached to a metal surface, the wetting properties and behavior can be significantly affected (Yuan & Lee, 15). In practice, densely-packed self-assembled monolayers (SAMs) can be used to modify the macroscopic properties of a solid surface (Dilimon et al. 202). Changes in wetting properties occur due to changes in the angle made by a liquid droplet whenever it is in contact with the surface. This phenomenon is significant in several contexts for example, in industrial contexts: this property is used to evaluate the cleanliness of semiconductor wafers. In such contexts, contact angles measurements are widely used. Control of this property is also useful during penetration of insecticides or pesticides into plants, and waterproofing of materials (Yuan & Lee, 25). While the former focuses on maximization of wetting, the latter case seeks to minimize liquid-induced wetting (Yuan & Lee, 28).

The purpose is to transfer biological samples from a gel to a membrane and their subsequent detection on the surface of the membrane. An antibody is used to specifically detect its antigen for protein analysis. The specificity of the antibody-antigen interaction enables a target protein to be identified in the middle of a complex protein mixture.

Because of their small size, ISFETs can be miniature diagnosis devices, allowing low sample consumption combined with a rapid response. ISFETs make the selective detection of certain ions in complex samples more efficient and can open

As indicated Eq. 1, oxygen is utilized as the physiological electron acceptor for lactate oxidation reaction. Therefore, the detection of lactate level using these biosensors is highly dependent on the oxygen concentration. On the other hand, oxygen concentration in blood is subject to fluctuations resulting in errors in measured lactate concentrations [19]. Moreover, oxygen deficiency in the blood sample deteriorates the detection range of the sensors [20]. The inadequate oxygen level cannot sustain the oxidation of lactate; thus, fluctuations in the oxygen concentration hinder accurate detection of lactate level. To eliminate the oxygen dependency problems in electrochemical sensors, some approaches have been proposed including the use of two dimensional cylindrical electrodes [21, 22], mass transport limiting films [21, 23], and tailoring the electrode surface with oxygen-rich materials [24]. In addition to the modification of electrode using one of the approaches listed above, some authors substituted lactate oxidase with lactate dehydrogenase (LDH) which does not require oxygen as an electron acceptor [25]. Although LDH does not use oxygen as an electron acceptor, NADH or NADPH coenzymes needs to be immobilized to enable the electron transfer between enzyme and electrode [8]. The modification of electrode to circumvent oxygen dependence of biosensors poses new problems associated with design, complexity, stability, and sensitivity [4]. In addition, the aforementioned methods hinder the miniaturization of the sensors

Implantable bioelectronics has become a popular research issue in the recent decades. At the same time, several heart diseases are common medical issues among the world. Thus, implantable cardioverter-defibrillator (ICD), one of the derivatives of implantable bioelectronics, was invented to lower the risk from sudden cardiac death. This essay will first briefly explain implantable cardioverter-defibrillator (ICD), and then evaluate the drawbacks arise from usage of ICD.

The electrodes were applied in measurements of extracellular pH during short-term regional ischemia in the swine heart and no-flow ischemia in the isolated rabbit papillary muscle. Results showed very low sensitivities for species such as Na+, K+, Li+, NH4+, Ca2+, Mg2+, dissolved oxygen, ascorbate, lactate, and urate. The studies on selectivity determined that none of the tested cations had an adverse effect on the potential response at the physiological pH level of 7. Results of the reproducibility of the electrodes also suggested that AEIROF-based pH electrodes can be used for pH measurements when an accuracy of ±0.02 is sufficient enough.

The semiconductor

The use of nano-materials and extreme precision micro-engineering has the potential for great improvement in the world of electronics and information technology by providing smaller, faster, and more powerful computers and this has been at the forefront of the nanotechnology commercialization . Great examples of how nanotechnology is currently being used in these fields are products such as processors, data storage, and memory components made with nano-materials, TVs, monitors and even smartphone screens that use organic light-emitting diodes (OLED), and waterproof electronics such as smartphones due to the application of nano-coatings

Fig. 3. Cyclic voltammograms (A) and Nyquist plots (B) recorded at bare GCE (a), β-Ni(OH)2/GCE (b) and β-Ni(OH)2@CDs/GCE (c) in a 0.1 M KCl solution containing 5 mM Fe(CN)63-/4-. Inset of Fig. 3B: Equivalent circuit applied to fit impedance measurements, where: Rs is the resistance of electrolyte solution; Rct is the charge transfer resistance, W is warburg impedance and CPE is constant phase element.