Author Archives: Rajesh Gandhi


Osmolality Measurements for High-Concentration Protein–Polymer Solutions: Variation Based on Working Principles of Osmometers

Osmolality is a critical attribute for injectable formulations. It is desirable to have products match physiological osmotic conditions. Furthermore, osmolality provides confirmation of soluble content in solution. Preventing injection of hypo- or hyperosmotic solutions is a key element of parenteral formulation development. Additionally, some investigators have explored correlations between injection pain and formulation osmolality, although no significant correlation has yet been observed (1–4). Osmolality is a valuable in-process test also because it provides a reliable and repeatable value that reflects…


The Importance of the Concentration-Temperature-Viscosity Relationship for the Development of Biologics

JIM DELILLO (WWW.FREEIMAGES.COM) Patient preference and a competitive landscape in the parenteral market have fueled the need for convenient delivery systems and a desire for less‑frequent dosing injections. Monoclonal antibodies (MAbs) often have high dose requirements, so they must be formulated at very high concentrations (1). At low concentrations, an antibody solution’s viscosity increases moderately as a function of protein concentration. But at high concentrations (>100 mg/ mL, depending on the molecule), viscosity increases exponentially (2, 3). Thus, a specification…