3:1 连接:3 kb 载体 100 ng + 1 kb 插入片段 → 加 100 ng 插入 标准克隆流程:100 ng 的 3000 bp 载体搭配 1000 bp 插入片段,按 3:1 摩尔比需要 插入ng = 3 × 100 × (1000÷3000) = 100 ng。即 0.051 pmol 载体、0.154 pmol 插入——20 µL 反应中为 2.564 nM 载体、7.692 nM 插入,稳超 T4 连接酶高效的约 1 nM 末端浓度。{"result":"Use 100 ng insert + 100 ng vector for 3:1 (0.154 vs 0.051 pmol); in 20 µL: 7.692 nM insert, 2.564 nM vector.","metadata":{"input":{"mode":"solveInsert","vectorSizeBp":3000,"vectorMassNg":100,"insertSizeBp":1000,"ratio":3,"reactionVolumeUl":20},"result":{"insertMassNg":100,"vectorPmol":0.051,"insertPmol":0.154,"actualRatio":3,"verdict":"within recommended band 1–5:1"}}}
比例核对:4 kb 载体 200 ng + 750 bp 插入 30 ng → 0.8:1,偏低 连接前核对:200 ng 的 4000 bp 载体与 30 ng 的 750 bp 插入片段——载体 0.077 pmol、插入 0.062 pmol,实际比例 0.8:1。750 bp 插入的建议区间是 3–5:1,该配置偏低——预期多为空载体自连;修正方法是将插入提高到 3 × 200 × (750÷4000) = 112.5 ng。{"result":"Actual ratio 0.8:1 — below recommended 3–5:1 for a 750 bp insert.","metadata":{"input":{"mode":"checkRatio","vectorSizeBp":4000,"vectorMassNg":200,"insertSizeBp":750,"insertMassNg":30},"result":{"vectorPmol":0.08,"insertPmol":0.06,"actualRatio":0.8,"recommendedBand":"3–5:1","verdict":"below recommended band 3–5:1"}}}