1. Consider your application of hyaluronic acid / sodium hyaluronate, choose a proper grade.
(application of sodium hyaluronate at: A Brief Introduction of sodium hyaluronate!)
For more details you can refer to:
Application of Injection Grade Hyaluronic Acid / Sodium Hyaluronate
2. Based on application choose proper molecular weight or intrinsic viscosity.
What Is High Molecular Weight Hyaluronic Acid / Sodium Hyaluronate?