Bio-Rad Model 785 Vacuum Blotter - Manual (Page 17)

6.3 Blotting Reagents
Catalog
Number
Product Description
162-0153 Zeta-Probe Membrane, sheets, 9 x 12 cm, 15
162-0154 Zeta-Probe Membrane, sheets, 10 x 15 cm, 15
162-0155 Zeta-Probe Membrane, sheets, 15 x 15 cm, 15
162-0156 Zeta-Probe Membrane, sheets, 15 x 20 cm, 15
162-0157 Zeta-Probe Membrane, sheets, 20 x 20 cm, 15
162-0158 Zeta-Probe Membrane, sheets, 20 x 25 cm, 3
162-0159 Zeta-Probe Membrane, roll 30 cm x 3.3 m, 1
162-0165 Zeta-Probe Membrane, roll 20 cm x 3.3 m, 1
162-0190 Zeta-Probe GT Membrane, 9 x 12 cm, 15
162-0191 Zeta-Probe GT Membrane, 10 x 15 cm, 15
162-0192 Zeta-Probe GT Membrane, 15 x 15 cm, 15
162-0193 Zeta-Probe GT Membrane, 20 x 15 cm, 15
162-0194 Zeta-Probe GT Membrane, 20 x 20 cm, 15
162-0195 Zeta-Probe GT Membrane, 20 x 25 cm, 3
162-0196 Zeta-Probe GT Membrane, 30 cm x 3.3 m, 1
162-0197 Zeta-Probe GT Membrane, 20 cm x 3.3 m, 1
161-0302 Sodium Dodecyl Sulfate (SDS), 1 kg
165-0962 Filter Paper Backing, 35 x 45 cm, 50 sheets
165-0921 Filter Paper Backing, 18 x 34 cm, 25 sheets
For more information on related products from Bio-Rad Laboratories see Bulletin
1900. For a complete list of molecular biology products refer to the Bio-Rad general
catalog.
Section 7
Appendix
7.1 Facts About Vacuum Transfer
Quantitative vacuum transfer mainly depends on three factors: transfer time, vacuum
pressure, and agarose concentration.
We studied the effect these three factors have on quantitive vacuum transfer. In our
study, we used four different sized target fragments: 0.8 kb, 4.1 kb, 15 kb, and 29 kb. We
electrophoresed 10 pg, 1 pg, and 0.5 pg of the target DNA fragments with a total
background DNA of 5 µg. Our experimental control was an overnight capillary
Southern. The densitometer readings of the overnight Southern on the 1 pg and 0.5 pg
lanes were our 100% transfer standard. Therefore, 100% vacuum transfer means the
vacuum transfer is equal to the overnight Southern transfer. Greater than a 100% vacuum
transfer means the vacuum transfer exceeded the Southern transfer. Efficiency of vacuum
transfer is calculated as follows:
% of Transfer = 100 x
O.D. of vacuum transfer
O.D. of overnight capillary transfer
We found the optimum vacuum transfer at 90 minutes using 5 inches of Hg with a
gel concentration of 0.7% agarose. We have summarized our work in the following
charts. The three essential factors in vacuum transfer are varied: time of transfer, vacuum
pressure, and gel concentration. The following charts illustrate the effect these factors
have on vacuum transfer.
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