Hyaluronic Acid Dynamics and its Interaction with Synovial Fluid Components as a Source of the Color Noise

Abstract

This work presents the process of physical crosslinking of hyaluronic acid (HA) in the presence of phospholipids (PL) as applied to the lubrication in articular cartilage system. Three time scales of the process have been studied using Molecular Dynamics simulation: 2[Formula: see text]ps, 200[Formula: see text]ps and 20[Formula: see text]ns. The simulations were carried out for long and short chains of HA in the presence and in the absence of PL. We show that in contrast to the macroscopic thermal (white) noise, the short-time noise on the molecular scale has the properties of color noise with the power spectrum distribution proportional to the inverse of frequency, [Formula: see text]. The long-time simulations are characterized by a power spectrum similar to that of white noise.