6336
Microneedle - mediated intradermal delivery of beta - galactosidase and formaldehyde - inactivated botulinum toxoid revealed effective deposition and subsequent diffusion within the dermis .
 formaldehyde
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: Chemical 
Text: {0} 
Answer:
 formaldehyde