[RASMB] FC43 fluorocarbon silicon oil

[Beld, Joris]

Dear all,
 
Maybe we are old fashioned but we still like to put a little bit (20-30 ul) of FC43 fluorocarbon silicon oil in the bottom of the sample sector (two sector centerpiece) during a sedimentation equilibrium run. Just to create a false bottom and prevent scatter problems at the edge (bottom) of the cell. Works fine and has been used a lot in the past. Lately we are almost running out of the oil, so I contacted Beckman and they told me the following:
 
"The fluorocarbon oil (306394) was used as part of the cell assembly and
added to the sample side of the 6- channel centerpiece to "lift" the sample in
the outer most sector above the cell bottom in order to collect more data in
that area. This approach was abandoned when the cell holes were
realigned shortly after the product launch near 1993 to better match the optical
track of the instrument. I don't recall the exact date, but the oil has been
discontinued for several years with no recommended replacement since it is no
longer needed."
 
Does anyone know what the composition of this FC43 fluorocarbon silicon oil is (or does someone knows another source from which we can buy it)?  (I asked Beckman but so far they do not want to give us the composition)
 
Of course I can forget about the oil and just do runs without it but for reproducibility and comparison with previous experiments we would really like to have some.
 
Thanks in advance.
Kind regards,
 
Joris Beld
Swiss Federal Institute of Technology