18506
In this study , to develop biostable nanoparticles with high tumor targetability , poly ( ethylene glycol ) - conjugated hyaluronic acid nanoparticles ( PEG - HANPs ) were mineralized through controlled deposition of inorganic calcium and phosphate ions on the nanoparticular shell via a sequential addition method .
 Chemical: poly ( ethylene glycol ); Chemical: PEG; Chemical: calcium; Chemical: phosphate
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: poly ( ethylene glycol ); Chemical: PEG; Chemical: calcium; Chemical: phosphate