Cell biopsy

The new tweezers will allow biopsies to be performed on individual living cells

Vladimir Guillen, Naked Science

Usually, in order to study the molecular composition of a single cell, it had to be opened and thereby killed. However, this process provides only one snapshot of the molecular structure of the cell at the time of its death. The new nanopincet, the device of which is described in the journal Nature Nanotechnology (Nadappuram et al., Nanoscale tweezers for single-cell biopsies), can provide an opportunity for long-term analysis of what is happening inside a single cell and a better understanding of how healthy cells work and what happens to patients.

A nanopincet is a glass rod with a tip less than 100 nanometers across, on which two carbon-based electrodes are placed. The application of electrical voltage to the tweezers creates a powerful electric field in close proximity to the electrodes, it can attract and capture biomolecules within 300 nanometers from the tip of the tweezers.

As soon as the molecule gets into this network, it "gets stuck" in it until the voltage is turned off. With this tweezers, researchers will be able to accurately pierce individual cells and select specific molecules.

Scheme and characteristics of the nanopincet 
© Imperial College London

Chemist Joshua Edel of Imperial College London applied the tweezers created by him and his team to extract DNA from the nuclei of human bone cancer cells without killing them. The researchers also "pulled out" pieces of protein-building information, known as mRNA molecules, from the cytoplasm of arterial cells.

The extraction of mRNA from two different points in one cell with a difference of one hour confirmed that the tweezers can be used to repeatedly obtain samples from one cell. In addition, the tweezers were able to get mitochondria from the nerve cells of the brains of mice.

"So far, all our work has been done in Petri dishes," says Edel.

In the future, the researchers plan to test the tweezers on cells contained in tissue samples.

Extracting DNA from the nuclei of individual cells will also allow scientists to scan this genetic material for mutations that support diseases. And tracking the molecular composition of cells will help in studying how cells respond to new drugs.

Portal "Eternal youth" http://vechnayamolodost.ru