Not sure that I understand your question completely, but you should probably start by escaping your string to prevent the second "
from terminating your string.
// Original:
a:"<font color=blue>testing!@#$%^&*()_+{}|:"<>?-=[]\;',./"
You can tell by the syntax highlighting that the original string is terminated premature.
// Escaped:
a:"<font color=blue>testing!@#$%^&*()_+{}|:\"<>?-=[]\\;',./"
By using the escape character \
you can tell JS to interpret the second "
as part of the string, and not a string terminator. You should also escape the \
character near the end of your string to prevent JS thinking you are using it to escape the ;
character.