User Manual

Nondenaturing Nucleic

Acid PAGE

9.1 Introduction

Criterion

™

TBE gels are used to separate small double-stranded DNA (dsDNA) fragments, particularly

PCR products. DNA molecules have nearly uniform mass-to-charge ratios, allowing nondenaturing

nucleic acid PAGE to separate dsDNA by mass using a continuous TBE buffer system.

9.2 Criterion TBE Gels

9.2.1 Gel Composition

Gel buffer 89 mM Tris, 89 mM boric acid, 2 mM EDTA, pH 8.3

Crosslinker 3.3% C

Stacking gel 4% T, 3.3% C

Storage buffer 89 mM Tris, 89 mM boric acid, 2 mM EDTA

Shelf life ~12 weeks at 2–8°C; expiration date is printed on each cassette

9.2.2 Gel Selection Guide

Gel Percentage Optimum Separation Range

5% 200–2,000 bp

10% 50–1,500 bp

15% 20–1,000 bp

4–20% 10–2,000 bp

9.3 Nondenaturing Nucleic Acid PAGE Buffers

See Appendix B for buffer formulations. Do not adjust pH unless directed to do so.

Running buffer (1x) 89 mM Tris, 89 mM boric acid, 2 mM EDTA

Dilute 100 ml 10x stock (catalog #161-0733) with 900 ml diH

Sample buffer (5x) 50 mM Tris-HCl, pH 8.0, 5 mM EDTA, 25% glycerol, 0.2% bromophenol

(catalog #161-0767) blue, 0.2% xylene cyanole FF

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