How to make backticks accept variables as variables?

In my bash script I have the following line

[backtick]mosquitto_pub -t '/$location/[backtick]

With this I want to 'publish' to the MQTT stream. The publishing part works great but it takes the variable name $location literally, and doesn't substitute $location with the initialized value for like NYC,Paris or Tokyo.

Q: How can make it so that the assigned value/string gets substituted to $location when the code is executed