Factors affecting protein distribution and structure in a dried droplet

Convective/diffusive drying of biopreservation solutions that contain biological macromolecules or organisms is widely-utilized, especially in desiccated and vitrified state preservation. Typically, solutions are deposited on a surface as thin films or droplets and are dried in a controlled environment. A typical biopreservation solution contains the biomaterial to be preserved, non-reducing sugars (trehalose, sucrose, etc.), polyols, and salts [1]. There are several factors that affect the overall stabilization and storage efficiency of a biopreservation solution: the properties of the chemicals in the solution, the thermodynamic state of the product to be stabilized, the processing conditions, and the interactions of the solution with the surface it is dried on. For example, during drying of a sessile droplet in a low relative humidity environment, secondary flows form within the droplet due to contact line pinning and non-uniform surface flux. These flows mainly cause accumulation of solutes at the droplet’s periphery [2]. An additional factor is the specific interactions among the constituents of the biopreservation solution, which can affect the stability of the biological material.Copyright © 2008 by ASME