Official websites use .gov
A
.gov website belongs to an official
government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you've safely
connected to the .gov website. Share sensitive
information only on official, secure websites.
Scanning electron microscope (SEM) images of the antigen loaded PLGA nanoparticles and microparticles with different copolymer ratio (50:50, 75:25 and 85:15), (A–F) after production, (G–L) after freeze-drying (powder state) and (M–R) after re-suspension in ultrapure water. The scale-bars shown at the bottom of each image represent 1 micron (A–C,H,I,N,O), 5 microns (D,E,F) or 4 microns (G,J–M,P–R).
