Primary human cells, taken straight from the body, are the most honest material for studying diseases and testing drugs. But getting foreign genetic material into them is tricky: cells don't like intruders. Standard methods either damage the cell or work unevenly, especially when the sample is heterogeneous — which it almost always is.

The new platform tackles this with a vortex flow. A whirlpool in a river spins up anything that gets caught in it. Here, fluid carrying cells flows through a narrow channel where a vortex is created: it captures cells of the desired size and holds them in the zone of an electric field. A brief electrical pulse opens temporary pores in each cell's membrane, letting genetic material slip inside: plasmid DNA or messenger RNA.

The authors tested the method on primary human cells and showed that it delivers both DNA and RNA. The platform automatically adjusts the electric field strength and buffer composition for each sample, so it works even with cells of different sizes and states. This is a step toward making non-viral gene delivery a routine procedure in labs and, potentially, in clinics.

A whirlpool that gently opens the cell's door and lets in the desired cargo: that's one way to describe this approach. It combines cell selection, parameter tuning, and delivery into one continuous process, making it convenient for broad use.