Re: how does a diabetic's glucometer work?

The glucometer works on an indirect way to measure blood glucose level.

The whole device is composed of:
- a lancet (presently a more automatized device which produces a nearly
painless puncture) to get a droplet of blood
- a reactive strip with an enzyme (usually glucose oxydase) and a reactive
(phenol or ferrocyanure, depending on the method used)
- a device (the "big box") including a digital display to perform the
dosage and display the result under numeric form (millimoles per liter
usually, but units may vary)

After blood has been spread on the reactive strip,glucose is transformed by
the enzyme  in D gluconolactone, wich in turn reacts with phenol or
ferrocyanure contained on the strip to produce a final substance. The more
glucose in the blood, the more final substance produced.

Dosage of this final substance can be achieved through colorimetry
(absorption of a monochromatic light by this final substance) or
impedancemetry.
Calibration of the machine allows to convert the dosage of this final
substance into a blood level of glucose