Utility of transporter/receptor(s) in drug delivery to the eye

Table 1 List of transporter/receptor(s) present in the eye

Tissue	Transporter/receptor	Subtypes	Ref.
Cornea	Amino acid	LAT1, LAT2, Phenylalanine, tyrosine	[213,214]
	Glucose	GLUT1	[215]
	Nucleoside		[216]
	Peptide	hPEPT1	[90]
	Folate		[180]
	Biotin		[175]
Conjunctiva	Acid-base	NKCC, HE1	[217]
	Amino acid	Bo,+	[218]
	Glucose	GLUT1	[157,219]
	Peptide	Dipeptide	[220]
	Monocarboxylate		[221]
	Nucleoside		[113]
Lens	Amino acid	System A, L, Gly, Ly+, β, ASC	[222]
	Ascorbic acid	SVCT2	[223]
	Glucose	GLUT1, GLUT3	[224]
	Glutathione	R-GSHT	[225]
Iris-ciliary body	Glucose	GLUT1, GLUT4	[226]
	Nucleoside		[227]
Retina	Amino acid	Glycine, glutamine, arginie, proline, taurine	[99,228,229]
	Glucose	GLUT1, GLUT3	[230]
	Monocarboxylic acid	MCT1, MCT3	[231,232]
	Nucleoside		[121,233]
	Peptide	PEPT1, PEPT2, PHT1, PHT2	[92,93,95,96]
	Vitamins(ascorbic acid, biotin, folic acid, riboflavin)	SVCT2, RFT, FR-α, SMVT	[85,183]