Bio-Rad Model 491 Prep Cell and Mini Prep Cell - Manual (Page 45)

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Continuous Electrophoresis Buffers
McLellan describes various continuous buffer systems from pH 3.8 to pH 10.2.3 (McLellan 1982). Use the
table below to prepare 1 liter of 5x continuous nondenatur ing PAGE buffer. DO NOT ad just pH with acid or
base. If the final pH is out side the the listed range dis card the buffer and remake.
Table 16. Nondenaturing PAGE buffer preparation.
Buffer pH ± 0.1
Basic Component
and MW
5x Solution
g/L or ml/L
Acidic Component
and MW
5x Solutions
ml/L or g/L
3.8
Beta-Alanine
89.09 mw
13.36 g/L
Lactic Acid
85% soln.
7.45 ml/L
4.4
Beta-Alanine
89.09 mw
35.64 g/L
Acetic Acid
17.4 M
11.5 ml/L
4.8
GABA
103.1 mw
41.24 g/L
Acetic Acid
17.4 M
5.75 g/L
6.1
Histidine
155.2 mw
23.28 g/L
MES
195.2 mw
29.5 g/L
6.6
Histidine
155.2 mw
19.4 g/L
MPOS
209.3 mw
31.4 g/L
7.4
Imidazole
68.08
14.64 g/L
HEPES
238.33 mw
41.7 g/L
8.1
Tris
121.14 mw
19.38 g/L
EPPS
252.2 mw
37.85 g/L
8.7
Tris
121.14 mw
30.29 g/L
Boric Acid
61.83 mw
7.73 g/L
9.4
Tris
121.14 mw
36.34 g/L
CAPS
221.3 mw
44.26 g/L
10.2
Ammonia
14.8 M
12.5 ml/mL
CAPS
221.3 mw
22.13 g/L
To make 1 L of 1x electrophoresis buffer, dilute 200 ml of 5x buffer with 800 ml deionized water. The final
concentrations of buffer should be as shown in Table 17.
Table 17. Final concentrations.
Buffer pH Basic Component Acidic Component
3.8 30 mM Beta-Alanine 20 mM Lactic Acid
4.4 80 mM Beta-Alanine 40 mM Acetic Acid
4.8 80 mM GABA 20 mM Acetic Acid
6.1 30 mM Histidine 30 mM MES
6.6 25 mM Histidine 30 mM MOPS
7.4 43 mM Imidazole 35 mM HEPES
8.1 32 mM Tris 30 mM EPPS
8.7 50 mM Tris 25 mM Boric Acid
9.4 60 mM Tris 40 mM CAPS
10.2 37 mM Ammonia 20 mM CAPS
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