The current invention relates to sensing elements and devices comprising at least one amphipathic lipid-binding protein or fatty acid binding protein, wherein the binding proteins are associated with a luminescent reporter group. The binding proteins and luminescent reporter groups are encapsulated within a hydrogel matrix that comprises at least one co-monomer, wherein the co-monomer is present at a concentration that decreases or inhibits micelle formation of the amphipathic lipid. Binding of the amphipathic lipid or fatty acid to the appropriate binding protein can produce at least one detectable change in the property of the luminescent reporter group.