A challenge to expanding continuous molecular monitoring beyond glucose is access to a biofluid containing meaningful concentrations of the analyte of interest. Blood is the most well characterized and well understood biofluid, but its continuous access is invasive. Many other biofluids, including tears, saliva, sweat, and urine, can be collected non-or minimally-invasively. These, however, are cumbersome or impossible to collect continuously and often fail to accurately reflect the analyte concentrations found in blood . The remaining biofluid option, interstitial fluid (ISF), is easily accessed in the dermis, as this tissue lies less than a millimetre beneath the skin surface. Dermal ISF is rich in biomolecules; it contains >90% of the proteins, RNAs, and metabolites found in blood, as well molecules unique to the ISF . A wide-ranging array of methods exist for access of dermal ISF including direct insertion of needle-based electrochemical sensor similar to those used in continuous glucose meters.