Hyaluronic acid of tailored molecular weight by enzymatic and acid depolymerization

Hyaluronic acid (HA) is a glycosaminoglycan crucial for the homeostasis of tissues, and its role on cell signalling and regulation of tissue injury and repair largely depends on HA molecular weight. Therefore, HA application in a variety of fields requires HA of defined size. While a number of enzymatic, chemical and physical methods exist for HA depolymerization, limited information is currently available for accurate planning of experiments. In the present work, we propose a pseudo-mechanistic model to describe depolymerization kinetics of HA with hyaluronidase, chondroitinase ABC and phosphoric acid. Data to feed the model was provided by monitoring molecular weight reduction by gel permeation chromatography with light scattering detection over 24 h. Five enzyme to substrate ratios and three temperatures were used for enzymatic and chemical reactions respectively, allowing for selection of operational parameters in a range of conditions. The model adequately reproduces the resulting data providing flexibility in the planning of the reactions to obtain HA of the desired molecular weight.