Finger pricking may be a means to an end for diabetics who need to track their blood glucose levels, but it's a pain — both literally and figuratively speaking. They say that necessity is the mother of invention, and the necessity for a better alternative to the finger-pricking method is cropping up some pretty neat innovations. Two are highlighted here. One of them is a nanosensor "tattoo," while the second is a near-market method that targets tear fluid as a non-invasive source of information.

According to a Technology Review article, a nanosensor "tattoo" is being developed to work with a modified iPhone to monitor levels of sodium, glucose, and other chemicals in the body. Northeastern University researchers applied their "tattoo" by injecting a solution containing carefully chosen nanoparticles into the skin. Unlike your average tattoo, it doesn't leave a visible mark, but the nanoparticles will fluoresce when exposed to a target molecule. The modified iPhone tracks changes in the fluorescence, which will be relayed to an application that will perform an analysis of the amount of the molecule present.

As a piece from Arizona State University points out, it's not just the action of finger pricking that serves as an annoyance — this method also requires diabetics to carry alcohol wipes, lancets, and other equipment to monitor themselves 2-10 times a day. The researchers developed a tear-based glucose sensor that eliminates the need for alcohol wipes and lancets, using a thermoset fluidic system to capture tear fluid from the eye before performing an assay of the glucose in the tear sample.