Bio-Rad ReadyPrep™ 2-D Cleanup Kit - Manual (Page 7)

Section 4
Instructions for Use
4.1 Protocol for Sample Volumes up to 100 µl
Use 1.5 ml microcentrifuge tubes for processing the protein
samples. Maintain the sample tubes in an ice bucket during
each step of the procedure unless otherwise specified.
Always position the microcentrifuge tubes in the centrifuge
in the same orientation (for example: cap hinge facing out-
ward) so that the protein pellet remains on the same side of
the tube after each spin. This will minimize loss of protein
pellets during centrifugation and washing steps.
For best results, the protein concentration of the sample
should be determined before beginning (see step 1). We
recommend the Bio-Rad RC DC Protein Assay for protein
quantitation because the assay is suitable for the widest
variety of samples and works in the presence of
detergents, reducing agents, and other agents that
interfere with other protein assays.
Refer to Section 5.1. for guidelines on the quantity of
sample needed with immobilized pH gradient (IPG) strips of
different lengths and with different staining(detection)
methods. This will help determine what the starting amount
of protein should be.
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