Generating QR Code with URL to record

I am trying to generate a QR code that will open a record in Quickbase.  I have a Formula URL field that generates the URL:

URLRoot() & "db/" & [_DBID_ASSETS] & "?a=dr&key=" & URLEncode([Cart ID#])

I have a Formula Rich Text field that generates the QR Code:

"<img src=\"http://chart.apis.google.com/chart?cht=qr&chs=100x100&chl="&[Record URL]
& "\"\"/>"

When I scan the QR Code it is dropping off the &key= part of the URL.  Is there something wrong with my Rich Text Formula?
The URL field works perfectly!

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Julie Meeker
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