Drying of Vaccines and Biomolecules.

Vaccines are the most important life-saving prophylactic medicines administered in maintaining global health. In a pandemic situation, the manufacturing, formulation followed by preservation of vaccine are challenging areas of concern looking at the dire need of administering it to several billion people on the planet in a pandemic like situation. An important area of major concern is the potential loss of vaccine activity during storage and transportation. Scientists have developed several innovative ideas to store vaccines for a longer period of time. This article focuses on a critical overview of various methods of vaccine storage in dry powder form. Conventional vaccine drying processes, such as freeze drying under different conditions, spray drying along with the upcoming novel technologies such as spray freeze drying are described in detail for the application in vaccine drying. Some other emerging methods, such as, microwave freeze drying and atmospheric freeze drying techniques are also discussed; these could be the game changers in the future. Several drying techniques make use of protective agents during the process of drying and storage. This review also highlights a comparative study of various technological challenges in drying of vaccines in support of the current global health scenario affected by COVID19. [ABSTRACT FROM AUTHOR]