12437
PLGA nanoparticles were about 120 nm in size , as determined by dynamic light scattering , with a surface negative charge of - 30 mV .
 Chemical: PLGA
Please list all entity words in the text that fit the category.Output format is "type1: word1; type2: word2". 
Option: Chemical 
Text: {0} 
Answer:
 Chemical: PLGA