class="Serp__item__snippet--34vQF">Addgene recommends making 1000X stock solutions and storing aliquots at -20°C. To use, dilute your antibiotic into your LB medium at 1:1,000. For example, to make 100 mL of LB/ampicillin growth media, add 100 μL of a 100 mg/mL ampicillin stock (1000X stock) to...