Good
glucose management through an insulin dose regime based on
the metabolism of glucose helps millions of people worldwide manage
their diabetes. Since Banting and Best extracted insulin, glucose
management has improved due to the introduction of insulin analogues
that act from 30 minutes to 28 days, improved insulin dose regimes,
and portable glucose meters, with a current focus on alternative sampling
sites that are less invasive. However, a piece of the puzzle is still
missingthe ability to measure insulin directly in a Point-of-Care
device. The ability to measure both glucose and insulin concurrently
will enable better glucose control by providing an improved estimate
for insulin sensitivity, minimizing variability in control, and maximizing
safety from hypoglycaemia. However, direct detection of free insulin
has provided a challenge due to the size of the molecule, the low
concentration of insulin in blood, and the selectivity against interferants
in blood. This review summarizes current insulin detection methods
from immunoassays to analytical chemistry, and sensors. We also discuss
the challenges and potential of each of the methods towards Point-of-Care
insulin detection.