biostudies-literatureNeri IEdinburgh Napier University379https://www.ebi.ac.uk/biostudies/studies/S-EPMC12843750biostudies-literatureUnknown31(2)A comprehensive two-dimensional liquid chromatography platform (LC × LC) was developed and validated for dermal permeability studies. In this implementation, the two separation dimensions were applied to mimic the layered structure of human skin: a ceramide-like stationary phase in the first dimension (¹D) to simulate the lipid-rich epidermis, and an immobilized artificial membrane (IAM) phase in the second (²D) to emulate the dermis. Experimental conditions were optimised to reflect the microenvironment of the in vivo skin. For validation purposes, 43 pharmaceutical and cosmetic compounds whose transdermal permeability coefficients (log K_p) were known from the scientific literature were selected as model solutes. A good degree of separation was achieved acMolecules (Basel, Switzerland)Integrated Biomimetic 2D-LC and Permeapad^® Assay for Profiling the Transdermal Diffusion of Pharmaceutical Compounds.PMC12843750n.a.Grumetto LRusso GStevens CNeri IfalseIntegrated Biomimetic 2D-LC and Permeapad^® Assay for Profiling the Transdermal Diffusion of Pharmaceutical Compounds.A comprehensive two-dimensional liquid chromatography platform (LC × LC) was developed and validated for dermal permeability studies. In this implementation, the two separation dimensions were applied to mimic the layered structure of human skin: a ceramide-like stationary phase in the first dimension (¹D) to simulate the lipid-rich epidermis, and an immobilized artificial membrane (IAM) phase in the second (²D) to emulate the dermis. Experimental conditions were optimised to reflect the microenvironment of the in vivo skin. For validation purposes, 43 pharmaceutical and cosmetic compounds whose transdermal permeability coefficients (log K_p) were known from the scientific literature were selected as model solutes. A good degree of separation was achieved ac2026-01-01T00:00:00Z2026 Jan2026-06-15T03:14:48.759Z2026-06-15T03:08:45.508ZS-EPMC128437504159942810.3390/molecules31020379