Mechanoelectrical transduction in hyaluronic acid salt solution is an entropy-driven process

Area of Science:

• Biophysics
• Physical Chemistry
• Solution Dynamics

Background:

• Hyaluronic acid salt solutions exhibit changes in optical rotary dispersion upon mechanical displacement.
• Previous research indicated mechanical strain alters the salt's optical properties.

Purpose of the Study:

• To investigate the relationship between mechanical displacement of hyaluronic acid salt solution and bound water loss.
• To explore the reversibility of these phenomena and their implications for entropy and time's arrow.

Main Methods:

• Applying gentle pressure to displace a column of hyaluronic acid salt solution.
• Measuring the electrical potential generated across the displaced column.
• Observing the movement of bound water across a membrane relative to the solution column.

Main Results:

• Displacement of the hyaluronic acid salt solution column generates an electrical potential.
• Loss of bound water across a membrane correlates with the extent of column displacement.
• Reversible return of the column to its resting position is accompanied by water returning across the membrane, albeit at a different rate.

Conclusions:

• Mechanical strain on hyaluronic acid salt induces a less entropic configuration, releasing bound water and increasing water entropy.
• The observed reversible changes in entropy distribution suggest a potential reversibility of time's arrow for the water component.