Tabletop Rotors and Tubes

Tubes and Accessories
LABWARE MATERIAL COMPATIBILITY WITH SOLVENTS AND SAMPLE
The chemical compatibility of tube materials with the gradientforming
medium or other chemicals in the solution is an important
consideration. Although neutral sucrose and salt solutions cause
no problems, alkaline solutions cannot be used in Ultra-Clear or
polycarbonate tubes. Polycarbonate and Ultra-Clear tubes are incompatible
with DMSO, sometimes used in the preparation of sucrose
gradients for sedimentation of denatured DNA. Refer to Appendix A
for detailed compatibility information.
GRADIENT FORMATION AND FRACTIONATION
Consideration should be given to gradient formation and fractionation
when choosing a tube for a density gradient run. If the bands or zones
formed during centrifugation are indistinct, they may not be visible
through a translucent material such as polyallomer. If optimum band
visualization is important, Ultra-Clear, polycarbonate, or cellulose
propionate tubes should be used. Whenever collection of bands or
zones must be done by slicing or puncturing the tube, a thin, flexible
tube wall is required. Ultra-Clear or polyallomer tubes should be used
in these cases, depending on the need for transparency.
LABWARE TYPES
➠ NOTE Tubes made of cellulose nitrate were formerly
used for various separations, particularly
rate-zonal separations. Beckman Coulter discontinued
the use of cellulose nitrate for tube
manufacture in 1980, due to inconsistent
physical properties inherent in the material.
If you currently have cellulose nitrate tubes,
dispose of them. Consult your laboratory safety
officer for proper disposal procedures.
Tabletop Ultracentrifuge Rotors and Tubes
2-3