/macrophages ) or compatibility with tissue biochemistry and cell signaling (e.g., phosphatidylserine and phosphatidylcholine with brain tissue ). The introduction of surfactants as "edge activators" is known to improve the flexibility of liposomes. Combined with the in-situ retention facilitated by the hydrogel, this feature can further enhance the potential of liposomes for effective (trans)dermal drug delivery. Nanostructured lipid carriers or solid lipid NPs have also been proposed as alternatives for the formulation of hybrid hydrogels for the delivery of hydrophobic drugs.