Therapeutic challenges in ocular delivery of lipid based emulsion

Figures & data

Fig. A1 Schematic illustration of the ocular barrier against the topical delivery of lipid based emulsion.

Fig. A2 Schematic representation drug fate in ocular drug delivery.

Table A1 Some recent development in the field of lipid based emulsion for ocular delivery.

Drug	Lipid	Surfactants	Improvement	References
Terbinafine hydrochloride	Isopropyl myristate/Miglyol 812)	Tween 80, Cremophor EL	Prolonged mean residence time and increased bioavailability	[31]
Ofloxacin	Oleic acid	Tween 80	Preocular residence time was improved	[45]
Pilocarpine hydrchloride	Soybean oil	Span 80, Brij 35P	Prolonged intraocular pressure lowering effect	[46]
Moxiflaxacin	Isopropyl myristate	Tween 80, Span 20	Longer precorneal residence, sustain the release of the drug	[47]
Gatiflaxacin	Isopropyl myristate	Tween 80, Transcutol P	Increased intraocular penetration and enhance ocular bioavailability of gatifloxacin	[48]

Fig. A3 A model of ternary Phase region depicting of different emulsion systems.

Fig. A4 Design consideration of lipid based for ocular drug delivery.

Table A2 Excipients used for the formulation of ocular lipid emulsion [75].

Oil	Emulsifiers	Lipids & Polysaccharide	Miscellaneous
Sesame oil	Cholesterol Phospholipid	Stearylamine	α–Tocopherol
Soya oil	Polysorbate 80	Oleylamine	Glycerol
Castor oil	Transcutol P	Chitosan	Xylitol
Paraffin oil	Cremophor RH	Arabinogalactan	Sorbitol
Paraffin light	Poloxamer 407	Hyaluronic acid	Thiomersal
Lanolin Vaselin	Poloxamer 188	Gellan gum	EDTA M
Corn oil	Miranol C2M	Alginic acid	Ethyl paraben
Glycerin monostearate	Tyloxapol	Hydroxypropylmethyl cellulose	Propyl paraben

Table A3 Patent granted on LEs for the ocular drug delivery.

Inventions summary	Application	Patent No	References
The patent claim that cyclosporine containing LEs administered in eye	Treatment of Phacoanaphylactic Endophthalmitis or Uveitis	US4649047A	[67]
Delivery hydrophobic pharmaceutical active ingredient through emulsion	Ocular delivery	US6007826A	[68]
The high concentration of surfactant are required to make thermodynamic stabilized the emulsion but when stored at long time lead color change (yellowish) because of rancid problem of fatty acid. This patent explains the solution to problem.	Eye lotion for treating the eyes	US6335022B1	[69]
The patent claim that develop composition use for lubricate the eye and corneal surface	Treatment of dry eye syndrome	US6656460B2	[70]
To improve the drug solubility and stability	Treatment of glaucoma	US8414904B2	[71]
The lipid emulsion containing alpha 2 adrenergic agonist and based on the neuropeptide inhibitor	Treatment Meibomian gland dysfunction and dry eye.	US9597328B2	[72]

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