rigging up pt100 flat film element

I just bought a few individual flat film pt100 elements (RS #362-9799),
which I intend to mount inside some 10mm or 8mm copper tube with one
end closed off, and wire the things up to an OMRON temerature
controller, and mount the copper tubes in to a liquid (actually beer).

I was originally thinking about wrapping the platinum element (2mmx10mm
in side - tiny) in some plumbers PTFE tape for electrical insulation.
My concern is that with the element in air, inside the copper tube, the
thermal response, or even accuracy won't be very good.

Can anybody think of a good way of mounting these pt100 elements? Some
heat transfer resin or something?

Cheers,
Mark