Healing Wounds With Diamonds

A team at Northwestern University, led by Dean Ho, has discovered that nanodiamonds are a wound's best friend. Insulin is very attracted to nanodiamonds and in addition to regulating blood sugar, insulin can accelerate the healing process and stave off infection in wound sites. Since the tiny diamond can be easily placed in a wound without causing further damage, this is an excellent way to get an increased amount of insulin there as well. From the article, "A substantial amount of insulin can be loaded onto the nanodiamonds, which have a high surface area. The nanodiamond-insulin clusters, by releasing insulin in alkaline wound areas, could accelerate the healing process and decrease the incidence of infection. Ho says this ability to release therapeutics from the nanodiamonds on demand represents an exciting strategy towards enhancing the specificity of wound treatment."

Comments

Re:Why?

[cfa22]

The insulin molecule has two patches on its surface that are predominantly hydrophobic (water-hating) that likely help it to stick to the pure-carbon surface of (nano)diamond. The "nano" bit just insures there is a large amount of surface area for insulin to stick to per unit mass of diamond. The investigators only showed that their nanodiamonds can suck up a lot of insulin; they are far from proving their insulin-loaded nanodiamonds are useful for wound-healing. The investigators only speculate that insulin would act as a growth hormone (generally thought to be its minor function; the major function being the transsystem signal for organism-wide glucose homeostasis). They point out the pH in a typical wound could approach 10.5, which would facilitate insulin release from nanodiamonds. (Such increases in alkalinity in beta cells, the pacreatic cells that produce insulin, are thought to trigger its release.) Unfortunately, it might also compromise insulin's ability to dock with its receptor, a necessary requirement for its function (either as a growth hormone or in glucose regulation). Directly injecting insulin into wounds speeds healing (sometimes by 50%) (Zhang et al, J. Surg. Res. 142:90 (2007) link), so it seems like the investigators have a plausible path to follow.