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Cloning & Expression

S-Gal™/LB Agar Blend Microwave Protocol



Add one pouch S-Gal/LB Agar Blend (complete with IPTG) to 500 ml deionized water.

Note: Powdered blend is stored at room temperature.
Time: 1-2 min.

Thoroughly mix S-Gal/LB Agar Blend in deionized water and microwave on high setting, just to boiling.
Time: 4-5 min.


Mix by swirling medium.
Note: This may be sufficient to dissolve the agar component. If not, heat for additional 15- to 30-second intervals, with mixing, until agar is in solution. To avoid "super heating", do not microwave unattended for extended periods.
Time: 5-8 min.

Add antibiotic supplement post-microwaving, after agar has cooled to approx. 50°C
Note: A 50°C water bath will minimize equilibration time.
Time: 10-30 min., if required.

Pour plates.
Note: S-Gal is not light sensitive. No need to protect plates from light.
Time: 10-15 min.

Total estimated time: 25 min.

For best results, allow plates to dry at room temperature, with lids on, for 16 hours following plating.

S-Gal is a trademark of Sigma Chemical Co.

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