Confocal micrograph

Treatments for human disease must overcome an incredible array of biological obstacles before they can succeed.  Having a drug that causes the desired effect in diseased tissue is only a small piece of the puzzle; the drug must also somehow accumulate in the diseased tissue, evade defensive responses by the immune system, avoid damaging healthy tissues, and navigate a whole host of other possible pitfalls within the body.

In this image, biologist Gaurav Sahay, engineer Avi Schroeder, and neuroscientist Paulina Hill tackle yet another biological obstacle to drug delivery: the cell membrane, which protects the cell by keeping foreign materials out. Gaurav, Avi and Paulina build tiny vehicles – actually, tiny lipid pouches – to help drugs cross this barrier and act on intracellular components.  Here, they capture a moment of success:  pouches made up of a particular combination of lipids (red) have successfully crossed the membrane and reached the inside of a nerve cell.