Liquid bandages

This may seem far-fetched, but I got a paper cut from picking up a cardboard box. The box slipped, and when I grabbed it, my finger brushed against the edge, leaving a large gash in my finger. Okay, maybe not “large,” but it hurt a lot and the cut was big enough that it needed to be covered. However, it was right on the joint such that a conventional bandage would overly restrict movement.


We have been keeping liquid bandages around because my oldest is allergic to the adhesive used on normal bandages. I decided to try one on myself.



The package consists of an applicator and a liquid activation solution. The applicators look like a plasticized cotton swab. When you dribble on four drops of the activator, the applicator becomes viscous. It’s great for paper cuts because you can apply some to the surface of the cut, pinch the skin together and in a minute, the wound will be glued shut.





The primary ingredient listed on the package is
2-Octyl Cyanoacrylate with paraben (a preservative).
Don’t ask me why, but the “cyanoacrylate” part sounded very familiar. I rummaged through my junk drawer and realized why: methyl cyanoacrylate is Krazy Glue. (Sure, this isn’t as dramatic as Charlton Heston at the end of Soylent Green.)


Besides letting people glue helmets to suspended steel beams, cyanoacrylates have found other uses such as forensic fingerprint detection, orthopedic surgery, and as a replacement for sutures. There’s some great bedtime reading on the effects of cyanoacrylate exposure, but basically the shorter methyl alcohol molecules result in a stiffer (and quicker-setting) bond that might not be ideal for large cuts. Methyl alcohol is also toxic.



Butyl cyanoacrylate has been in use in Europe since the 70s and is still used in animal care. Butyl alcohol is far less toxic, though it can cause mild skin irritation. You can buy drops at the drug store.


Octyl cyanoacrylate the kind used in the brand name liquid bandages you can buy in the store. Octyl alcohol (octohol) is considered non-toxic. The bond is flexible, but takes longer to set. An additional benefit is its ability to inhibit bacteria growth. (Think of this as reducing the likelihood of a staph infection.)



A tube of Krazy Glue will set you back $1.39 for a 0.106 ounce tube.
A 60-drop tube (0.034 ounces, about 1/3 the size) of butyl cyanoacrylate costs is about $5. Band Aid brand liquid bandages are $7.08 for 10 applications. If I were equipping a kit for field use, I’d go for the butyl cyanoacrylate drops.



Further reading:
Nathan Schwade, MD on Wound Adhesives
FDA guidance on cyanoacrylates as tissue adhesive

Cool stuff on polymers — this taxes my tenous grasp of organic chemistry.