Electronic Detection Of Biomolecules Research Articles

Design Considerations of Si-NW FET Based Biosensor: A Review

Nano-technology is blooming in all the fields. The use of nano-transistors in bio-sensing applications has enhanced the scope of bio-molecules detection. The traditional chemical detection of bio-molecules leads to later side-affects. In order to overcome this, electronic detection of bio-molecules is much required. Despite its advantages in detection, this technology has not reached its peak because of its design considerations and its constraints. In this study we discuss about various constraints involved in design of Si-NW based biosensor

Light-Enhanced Blue Energy Generation Using MoS2 Nanopores

Summary Blue energy relies on the chemical potential difference between solutions of high and low ionic concentrations, potentially providing an independent energy source at estuaries around the world. The energy conversion relies on reverse electrodialysis via ion-selective membranes. A novel generation of these membranes is based on nanopores in atomically thin material. Single nanopores in molybdenum disulfide (MoS2)-based membranes have shown record-high power outputs in alkaline conditions. By increasing the surface charge of MoS2 membranes by light, we can double the osmotic power generated by a single nanopore at a neutral pH. The increased surface charge at the pore rim enhances the ion selectivity and leads to a larger osmotic voltage (dominating in small pores), while the increased surface charge of the membrane enhances the surface conductance, leading to a larger osmotic current (dominating in larger pores). The combination of these effects could efficiently boost the energy generation using membranes containing arrays of nanopores of varying sizes.

Synchronized optical and electronic detection of biomolecules using a low noise nanopore platform.

In the past two decades there has been a tremendous amount of research into the use of nanopores as single molecule sensors, which has been inspired by the Coulter counter and molecular transport across biological pores. Recently, the desire to increase structural resolution and analytical throughput has led to the integration of additional detection methods such as fluorescence spectroscopy. For structural information to be probed electronically high bandwidth measurements are crucial due to the high translocation velocity of molecules. The most commonly used solid-state nanopore sensors consist of a silicon nitride membrane and bulk silicon substrate. Unfortunately, the photoinduced noise associated with illumination of these platforms limits their applicability to high-bandwidth, high-laser-power synchronized optical and electronic measurements. Here we present a unique low-noise nanopore platform, composed of a predominately Pyrex substrate and silicon nitride membrane, for synchronized optical and electronic detection of biomolecules. Proof of principle experiments are conducted showing that the Pyrex substrates have substantially lowers ionic current noise arising from both laser illumination and platform capacitance. Furthermore, using confocal microscopy and a partially metallic pore we demonstrate high signal-to-noise synchronized optical and electronic detection of dsDNA.

Integrated electronic detection of biomolecules

Electronics offers several unique opportunities for the detection and characterization of biomolecules such as oligonucleotides and proteins. Solid-state microfabrication technology, similar to that used to make integrated circuits, can be employed to make integrated electronic sensing systems that are capable of simultaneously detecting multiple molecules. Here, we review some of the capabilities afforded by electronics for rapid and sensitive detection of biomolecules and discuss a recent demonstration of a multi-marker electronic sensing system for detection of uropathogens in clinical samples.

Carbon nanotube transistors for biosensing applications

Electronic detection of biomolecules, although still in its early stages, is gradually emerging as an effective alternative to optical detection methods. We describe field effect transistor devices with carbon nanotube conducting channels that have been developed and used for biosensing and biodetection. Both transistors with single carbon nanotube conducting channels and devices with nanotube network conducting channels have been fabricated and their electronic characteristics examined. The devices readily respond to changes in the environment, and such effects have been examined using gas molecules and coatings with specific properties. Device operation in (conducting) buffer and in a dry environment--after buffer removal--is also discussed. Applications in the biosensing area are illustrated with three examples: the investigation of the interaction between devices and biomolecules, the electronic monitoring of biomolecular processes, and attempts to integrate cell membranes with active electronic devices.