Biologic Velcro

Pectin, a polysaccharide that functions as an adhesive between plant cells, is also one of the few polysaccharides with anti-inflammatory and immunomodulatory benefits. As well as being used in the food industry for its thickening, gelling and emulsification properties – and its biodegradability and biocompatibility – pectin also has biomedical applications in drug delivery and tissue healing.

A new study (1) investigates the potential for pectin as a biopolymer adhesive for corneal wound healing, particularly in post-routine corneal incisions – as a sealant to reduce wound leakage caused by variations in intraocular pressure – and in targeted drug delivery for traumatic injuries. 

“We’ve been interested in glycocalyceal entanglement for years,” says Steven Mentzer, Professor of Surgery at Harvard Medical School. “Pectin entangles with the native glycocalyx; it’s essentially a biologic Velcro. Pectin is also a hydrogel with the potential for targeted drug delivery to the cornea.”

To assess the adhesive characteristics of pectin, the researchers used a bovine globe model as well as globes taken from Wistar rats. The pectin films – molded into tape form – were more adherent than control biopolymers (nanocellulose fibers, sodium hyaluronate, and carboxymethyl cellulose), and the adhesion strength got close to maximum within just seconds of contact, suggesting the potential for pectin to be used as an effective corneal incision sealant. Notably, the pectin films were able to resist anterior chamber pressure fluctuations from negative 51.3 ± 8.9 mm Hg to positive 214 ± 68.6 mm Hg. Biologic velcro indeed.