How to ‘weld’ neurons with a laser

February 9, 2016

An illustration of how a femtosecond laser pulse is delivered to the target point between an axon and a neuronal soma (cell body) (credit: the authors)

University of Alberta researchers have developed a method of connecting neurons using ultrashort laser pulses. The technique gives researchers complete control over the cell connection process and could lead to new research and treatment methods, including physical reattachment of severed neurons right after injury, the researchers say.

The team’s findings are published in the open-access Nature journal Scientific Reports.


After putting two neurons in a special solution that prevents them from sticking together, the researchers brought them into contact with each other and delivered femtosecond (10-15 seconds) laser pulses to the meeting point of the two cells, causing them to establish solid bonds and form a common membrane at the targeted area.

(Left): An illustration of the phospholipid bilayers of the neuron soma and axon (the attachment region is designated with a circular spot — not the laser focal point). (Center): The laser pulse’s high intensity causes a reversible destabilization of both phospholipid layers. The generated free ions (red) and free electrons (orange) cross the center nonpolar region and break bonds between the fatty acid hydrophobic tails. (Right): The relaxation process results in the formation of new stable bonds and formation of singular, hemifused, cell membrane only at the targeted connection point. (credit: Nir Katchinskiy et al./ Scientific Reports)

The cells remained viable and the connection strong. It took the neurons just 15 milliseconds to stick to each other; the process would have taken hours to occur naturally.

“The preservation of the viability of the neural network will allow researchers to study new complex pathophysiological processes, such as neurogenesis, Wallerian degeneration, segmental demyelination, and axonal degeneration,” the authors note.

Abstract of Novel Method  for Neuronal Nanosurgical Connection

Neuronal injury may cause an irreversible damage to cellular, organ and organism function. While preventing neural injury is ideal, it is not always possible. There are multiple etiologies for neuronal injury including trauma, infection, inflammation, immune mediated disorders, toxins and hereditary conditions. We describe a novel laser application, utilizing femtosecond laser pulses, in order to connect neuronal axon to neuronal soma. We were able to maintain cellular viability, and demonstrate that this technique is universal as it is applicable to multiple cell types and media.