In vivo and qualitative studies investigating the translational potential of microneedles for use in the older population
Independently, both transepidermal water loss (TEWL) and percutaneous absorption measurements accurately gauge stratum corneum skin water barrier integrity. Both TEWL and percutaneous absorption rates increase when the integrity of the SC barrier is compromised. Experiments to discern a quantitative and/or qualitative correlation between the two indicators have resulted in controversy. This paper reviews some major studies investigating this correlation.