Concentration of Fluorescein in Tear Fluid after Instillation as Eye-Drops

1979 ◽  
Vol 11 (2) ◽  
pp. 83-89 ◽  
Author(s):  
H. Barendsen ◽  
J.A. Oosterhuis ◽  
N.J. van Haeringen
Keyword(s):  
Tear Fluid ◽  
Eye Drops

Concentration of Fluorescein in Tear Fluid after Instillation as Eye-Drops

1979 ◽  
Vol 11 (2) ◽  
pp. 73-82 ◽  
Author(s):  
H. Barendsen ◽  
J.A. Oosterhuis ◽  
N.J. van Haeringen
Keyword(s):  
Tear Fluid ◽  
Eye Drops

scholarly journals Biopharmaceutics of Topical Ophthalmic Suspensions: Importance of Viscosity and Particle Size in Ocular Absorption of Indomethacin

Pharmaceutics ◽  
2021 ◽  
Vol 13 (4) ◽  
pp. 452
Author(s):  
Elisa Toropainen ◽  
Sara Fraser-Miller ◽  
Dunja Novakovic ◽  
Eva M. Del Amo ◽  
Kati-Sisko Vellonen ◽  
...  
Keyword(s):  
Particle Size ◽  
Aqueous Humor ◽  
Tear Fluid ◽  
Eye Drops ◽  
Particle Sizes ◽  
Drug Bioavailability ◽  
Ocular Absorption ◽  
Drug Concentrations ◽  
Biological Tests ◽  
Ocular Pharmacokinetic

Eye drops of poorly soluble drugs are frequently formulated as suspensions. Bioavailability of suspended drug depends on the retention and dissolution of drug particles in the tear fluid, but these factors are still poorly understood. We investigated seven ocular indomethacin suspensions (experimental suspensions with two particle sizes and three viscosities, one commercial suspension) in physical and biological tests. The median particle size (d50) categories of the experimental suspensions were 0.37–1.33 and 3.12–3.50 µm and their viscosity levels were 1.3, 7.0, and 15 mPa·s. Smaller particle size facilitated ocular absorption of indomethacin to the aqueous humor of albino rabbits. In aqueous humor the AUC values of indomethacin suspensions with different particle sizes, but equal viscosity, differed over a 1.5 to 2.3-fold range. Higher viscosity increased ocular absorption 3.4–4.3-fold for the suspensions with similar particle sizes. Overall, the bioavailability range for the suspensions was about 8-fold. Instillation of larger particles resulted in higher tear fluid AUC values of total indomethacin (suspended and dissolved) as compared to application of smaller particles. Despite these tear fluid AUC values of total indomethacin, instillation of the larger particles resulted in smaller AUC levels of indomethacin in the aqueous humor. This suggests that the small particles yielded higher concentrations of dissolved indomethacin in the tear fluid, thereby leading to improved ocular bioavailability. This new conclusion was supported by ocular pharmacokinetic modeling. Both particle size and viscosity have a significant impact on drug concentrations in the tear fluid and ocular drug bioavailability from topical suspensions. Viscosity and particle size are the key players in the complex interplay of drug retention and dissolution in the tear fluid, thereby defining ocular drug absorption and bioequivalence of ocular suspensions.

Tear fluid-eye drops compatibility assessment using surface tension

2016 ◽  
Vol 43 (2) ◽  
pp. 275-282 ◽  
Author(s):  
Martina Hotujac Grgurević ◽  
Marina Juretić ◽  
Anita Hafner ◽  
Jasmina Lovrić ◽  
Ivan Pepić
Keyword(s):  
Surface Tension ◽  
Tear Fluid ◽  
Eye Drops

Relationship between precorneal retention of viscous eye drops and tear fluid composition

1992 ◽  
Vol 16 (1) ◽  
pp. 23-26 ◽  
Author(s):  
A. Ludwig ◽  
N. J. van Haeringen ◽  
V. M. W. Bodelier ◽  
M. Van Ooteghem
Keyword(s):  
Tear Fluid ◽  
Fluid Composition ◽  
Eye Drops ◽  
Viscous Eye Drops

Kinetics ofγ-cyclodextrin nanoparticle suspension eye drops in tear fluid

2013 ◽  
Vol 92 (6) ◽  
pp. 550-556 ◽  
Author(s):  
Gauti Jóhannesson ◽  
Maria D. Moya-Ortega ◽  
Gudrún Marta Ásgrímsdóttir ◽  
Sigrún H. Lund ◽  
Margrét Thorsteinsdóttir ◽  
...  
Keyword(s):  
Tear Fluid ◽  
Eye Drops ◽  
Nanoparticle Suspension

Discovering the difference in the tear fluid proteome between Graves' patients with or without orbitopathy

2016 ◽  
Author(s):  
Cecilie Aas ◽  
Ingrid Nordheim ◽  
Eriksen Erik Fink ◽  
Bornick Ellen Charlotte ◽  
Thorsby Per Medboe ◽  
...  
Keyword(s):  
Tear Fluid ◽  
The Difference
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