Continuous Monitoring of Electrical Activity of Pancreatic β-Cells Using Semiconductor-Based Biosensing Devices

Abstract

The nonrelativistic energies of the core-excited 1s2sns 4 S (n = 3, 4, 5 and 6) states for the lithium isoelectronic sequence from Li I to O VI are calculated with a full core plus correlation method using multiconfiguration wavefunctions. Relativistic and mass-polarization effects on the energy are evaluated at the first-order perturbation theory by using the Pauli-Breit operators. Our results are in close agreement with experiment and are better than other theoretical results.

Ion Sensitive Transparent-Gate Transistor for Visible Cell Sensing

“…A high H + concentration is considered to have resulted around the cell membrane/gate oxide interface, caused by the elimination of CO 2 . In our previous works, we reported some results for the electrical monitoring of cellular respiration activity using a silicon-based FET biosensor. ,, The oxidized gate membrane is very sensitive to changes in the concentration of H + based on the equilibrium reaction with hydroxyl groups, while cellular respiration causes the release of lactic acid and carbon dioxide from living cells, which dissolve into solutions resulting in the generation of H + . Therefore, the IS-TGT with the oxidized thin film can selectively recognize changes in pH induced by cellular activity during metabolic changes.…”

“…The eliminated CO 2 is dissolved in a solution so that hydrogen ions are generated in accordance with the equilibrium reaction. Therefore, the pH variation can be easily detected by use of the semiconductor principle. ,, Figure shows the change in surface potential for cultured HeLa cells on the gate surface of the IS-TGT. A culture medium including glucose and serum was used for the medium change at the start of measurement, and subsequently the measurement solution was exchanged with a glucose- and serum-free medium after about 19 h. The IS-TGT with the cells exhibited clearly a potential response to the medium change, although no potential response was observed for the control IS-TGT without the cells, as shown in Figure A.…”

“…The direct detection of ions enables the straightforward analysis of various biomolecular recognition events. The principle of semiconductor-based biosensor on the basis of the field effect, a field-effect transistor (FET)-based biosensor (bio FET), can be utilized to directly detect ionic behavior in a solution. , In a few decades, some methods for the electrical measurement of cellular functions using the bio FETs have been reported. − The principle of the bio FET is based on the potentiometric detection of changes in charge density caused by specific biomolecular reactions at a gate insulator/solution interface. Ionic charges induced at the gate insulator electrostatically interact with electrons in a silicon substrate across a thin gate insulator, resulting in a change in the threshold voltage.…”

Surface Plasmon Resonance for Cell-Based Clinical Diagnosis

“…Non-invasive real-time observations and the evaluation of living cell conditions and functions are increasingly desired, not only for basic research in life sciences, but also for various medical practices. To date, various living cell reaction-based biosensors, such as impedance sensors [ 1 , 2 ], quartz crystal microbalance (QCM) sensors [ 3 , 4 ] and field effect transistor (FET) sensors [ 5 , 6 ] have been reported. Optical biosensors, surface plasmon resonance (SPR) sensors and resonant waveguide grating (RWG) sensors [ 7 , 8 ] also have been applied for the detection of living cell reactions in response to stimuli without any labeling.…”

Real-Time Monitoring of Potassium Ion Release Due to Apoptosis with Cell-Based Transparent-Gate Transistor

“…1) Recently, some original manners for electrical measurement of cell functions have been performed using the semiconductor devices. [2][3][4][5][6][7][8] The principle of semiconductor-based biosensing devices is based on the potentiometric detection of charge density changes induced at a gate insulator/solution interface accompanied by specific bio-molecular recognition events. Ionic charges at the gate insulator electrostatically interact with electrons in silicon crystal across the thin gate insulator resulting in the threshold voltage change.…”