Probing the Living Cell

Probing the Living Cell

Nanotechnology is offering up new methods to unravel the workings of the tiny human cell -- the basic building block of our body’s tissues.

Think of poking a hole in a cell and sticking in a flashlight.

Tuan Vo-Dinh

A unique nanobiosensor developed by Duke biomedical engineering Professor Tuan Vo-Dinh represents a significant advance for systems biology -- the ability to study the molecular and biochemical activities of a single cell in real time, without destroying the cell itself. Traditional analysis techniques break the cell apart and interpret cell activity out of the pieces.

Vo-Dinh and his team at Duke, postdoctoral associate Yan Zhang and doctoral student Jason Hsinnenwang, continue to further develop the nanobiosensor, which consists of an optical fiber with the tip stretched to a fine point the size of 50 nanometers -- about 2000 time smaller than a human hair. The nanofiber tip is coated with bioreceptors such as antibodies, snippets of DNA, proteins or peptides specifically chosen to target compounds of interest in a cell. The nanobiosensor can be inserted into a single cell -- without disrupting the cell’s functions. Under laser excitation, the probe literally lights up when the bioreceptors detect their targets, providing direct insight to the cell’s biomolecular activities.

Vo-Dinh plans to use the nanobiosensor to study cancer biomarkers and to evaluate the cell death process triggered by cancer drugs. Using animal cells, the team has already used the nanoprobe to identify the presence of toxic chemicals. This research is funded by the National Institutes of Health.