You can use way mentioned by RIAstar:
<fx:Object id="abc1" field1="\{*\}"/>
\
Or you can use real binding to make it treat anything inside it as a code, and then pass simple string without escaping {
and }
inside it:
<fx:Object id="abc" field1="{'{*}'}"/>
You can also use binding to a function that returns something if you need to set field to something more complex.