Scientists Develop Smallest Current Measuring Device

The carbon nanopipette, which can also be used to inject certain fluids into cells without damaging or disable the growing of the respective cell, is the smallest of its kind, with a width measuring only a thousand of the diameter of a human hair. Such micropipettes made out of glass can be routinely found in research laboratories around the world. Their properties make them extremely brittle, and can break during operation, causing irreparable damage to the cellular walls.

As you probably know glass is one of the best known electrical isolators, thus such a device cannot carry out simultaneous operations such as material injection and electrical current measurement. The carbon nanopipette designed by the University of Pennsylvania can be easily mass produced and eliminates most of the difficulties experienced while using glass pipettes.

Carbon nanotubes can be manufactured in a wide variety of sizes and widths and are much more flexible than glass. For example, the carbon nanopipette flexes while being pressed onto a hard surface, but recovers its original shape soon after.

The good current conducting properties of the carbon, can be exploited in the sense of making measurements of the electrical current in the respective cell, during the process of fluid injection, which gives a pretty accurate detection of the presence of proteins inside the cell.

Michael Schrlau, one of the first authors of the study conducted at Penn's Micro-Nano Fluidics Laboratory, reveals the fabrication process of the carbon nanopipettes. The manufacturing stage involves depositing a carbon film onto a quartz base, shaped in the form of a nanopipette. After the carbon depositing process is over the quartz base is gently removed to extract the carbon nanopipette. By using this particular method, Schrlau argues that multiple such devices may be constructed without using extremely complex manufacturing assemblies.

By using carbon nanopipettes as a tool in nanosurgery cellular processes may be observed in order to better understand the chemical reactions which take place inside the living cell. This could further contribute to the development of new drugs. So far, until the team finds collaborations in the scientific community the newly developed tool is still in the POC stage