Ocular Delivery of Biopharmaceuticals

Thiolated poly(aspartic acid) as potential in situ gelling, ocular mucoadhesive drug delivery system

“…Mucins are large glycoproteins which are mainly composed of a protein core, carbohydrates and are well glycosylated. There are two types of ocular mucins: membrane-associated and secreted mucins (Lorentz and Sheardown, 2014 Mucoadhesion can be described in three steps: (1) the formation of an intimate contact between the mucoadhesive preparation and the mucus, followed by the wetting of the mucoadhesive formulation; (2) the swelling of the macromolecules and the formation of an interpenetrating network with the mucus macromolecules; and (3) chemical bond formation (primary or secondary) between the entangled chains (Duchêne et al, 1988). Thus physical and chemical interactions can arise during the process of mucoadhesion.…”

Cationic Thiolated Poly(aspartamide) Polymer as a Potential Excipient for Artificial Tear Formulations

“…For normal vision, continuous moistening of the ocular surface is needed. Important roles are played in this by a sufficient quality of tears, maintenance of the normal composition of the tear film, normal lid closure, and regular blinking [ 1 , 2 ]. If equilibrium is lost, the DED can occur, resulting in eye discomfort and visual disturbance [ 2 , 3 ].…”

Mucoadhesive polymers in ophthalmic therapy

“…Measurements were carried out in duplicate and were made at 35°C, corresponding to the temperature of the eye surface. Lachrymal fluid washings were collected in beakers after 2,5,10,20,30 and 60 min, and measured with a spectrofluorimeter at 494 nm excitation wavelength and 521 nm emission wavelength (LS50B, Perkin Elmer) . HEC gels under the same experimental conditions were used as reference.…”