Osmolality of various viscoelastic substances: comparative study
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Updated: Oct 13, 2026

Rapid Viscoelastic Characterization of Airway Mucus Using a Benchtop Rheometer
Published on: April 21, 2022
H B Dick1, A J Augustin, N Pfeiffer
1Department of Ophthalmology, Johannes Gutenberg-University, Mainz, Germany. bdick@mail.uni-mainz.de
Purpose:
To determine the osmolality of various viscoelastic substances.
Setting:
Department of Ophthalmology, Johannes Gutenberg-University, Mainz, and Institute for Medical Device Testing, Memmingen, Germany.
Methods:
The analysis was carried out according to the European Pharmacopoeia by means of a calibrated osmometer using the freezing-point depression method. Each syringe was analyzed as a duplicate analysis.
Results:
Mean osmolalities (mOsmol/kg) of the sodium hyaluronate viscoelastic substances were Allervisc 299; Allervisc Plus 307; Amvisc Plus 335; AMO Vitrax 284; Biolon 279; Dispasan 311; Dispasan Plus 314; Healon 295; Healon GV 312; Healon5 322; HYA-Ophtal 376; Microvisc 313; Microvisc Plus 341; Provisc 307; Rayvisc 312; Viscoat 340; Visko 296; Visko Plus 319. Mean osmolarities of the hydroxypropyl methylcellulose viscoeslatic substances were Adatocel 278; HPMC Ophtal L 358; HPMC Ophtal H 360; La Gel 317; OcuCoat 309; Visco Shield 376.
Conclusions:
There were significant differences in osmolality among viscoelastic substances, which may explain the differences in corneal thickness after cataract surgery. A viscoelastic substance with an osmolality of 305 mOsmol/kg or slightly higher is preferable, especially in patients with a compromised corneal endothelium.
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