QC Lab Toolkit
QC Lab Toolkit · 5 in 1: Standard Solution Prep / Unit Conversion / Dilution / pKa Lookup / Mobile Phase Recipes. Runs locally — no data uploaded.
Standard Solution Prep Calculator
Compute the mass to weigh from a target concentration and volume, or vice versa.
Tip: Molar concentration requires molecular weight; mass-based concentration (mg/mL) is independent of MW but MW is still needed for switching. For weighing: under 100 mg use a 0.01 mg balance; over 100 mg use a 0.1 mg balance.
Unit Converter
Common analytical-chemistry unit conversions. Pick a category, then enter a value.
Note: Molar concentration requires molecular weight; ppm in dilute aqueous solution ≈ mg/L.
Molar Concentration Conversion (MW required)
Mass concentration ↔ molar concentration
Dilution Calculator
C₁V₁ = C₂V₂ single-step dilution (4 modes) / serial gradient dilution
Formula: C₁ × V₁ = C₂ × V₂ · Pick any mode below and enter 3 known values to calculate the 4th
| Level | Concentration | Take from prev. | + Diluent | Total volume |
|---|---|---|---|---|
| Stock | 1,000 μg/mL | — | — | — |
| L1 | 500 μg/mL | Take L0 500 μL | + 500 μL | 1,000 μL |
| L2 | 250 μg/mL | Take L1 500 μL | + 500 μL | 1,000 μL |
| L3 | 125 μg/mL | Take L2 500 μL | + 500 μL | 1,000 μL |
| L4 | 62.5 μg/mL | Take L3 500 μL | + 500 μL | 1,000 μL |
| L5 | 31.25 μg/mL | Take L4 500 μL | + 500 μL | 1,000 μL |
| L6 | 15.625 μg/mL | Take L5 500 μL | + 500 μL | 1,000 μL |
pKa Lookup Table
Common acids, bases, buffer salts and drugs with their pKa values — for mobile-phase pH selection and ionization-state prediction.
| Compound | pKa | Type | CAS | Use / Notes |
|---|---|---|---|---|
| 醋酸 (Acetic acid) | 4.76 | Acid | 64-19-7 | 常用缓冲 pH 3.8-5.8 |
| 甲酸 (Formic acid) | 3.75 | Acid | 64-18-6 | LC-MS 常用添加剂 0.1% |
| 三氟乙酸 TFA | 0.23 | Acid | 76-05-1 | 蛋白/多肽分析常用，但抑制 ESI |
| 七氟丁酸 HFBA | 0.0 | Acid | 375-22-4 | 强离子对试剂 |
| 磷酸 (Phosphoric acid) | 2.16 / 7.21 / 12.32 | Acid | 7664-38-2 | 三元酸，宽 pH 缓冲 |
| 柠檬酸 (Citric acid) | 3.13 / 4.76 / 6.40 | Acid | 77-92-9 | 生物样品常用 |
| 碳酸 (Carbonic acid) | 6.35 / 10.33 | Acid | 463-79-6 | CO₂ 溶于水 |
| 醋酸铵 (Ammonium acetate) | 4.76 / 9.25 | Buffer | 631-61-8 | LC-MS 通用缓冲盐 pH 4-9 |
| 甲酸铵 (Ammonium formate) | 3.75 / 9.25 | Buffer | 540-69-2 | LC-MS 首选 pH 3-4 |
| 碳酸氢铵 (Ammonium bicarbonate) | 6.35 / 9.25 | Buffer | 1066-33-7 | 蛋白/肽 LC-MS 常用 |
| 三乙胺 (Triethylamine) | 10.75 | Base | 121-44-8 | 碱性添加剂，封尾硅胶硅羟基 |
| 二乙胺 (Diethylamine) | 10.93 | Base | 109-89-7 | 碱性添加剂 |
| 氨水 (Ammonia) | 9.25 | Base | 1336-21-6 | 挥发性碱，LC-MS 兼容 |
| 哌嗪 (Piperazine) | 9.8 / 5.5 | Base | 110-85-0 | 双胺缓冲 |
| 阿司匹林 (Aspirin) | 3.5 | Acid | 50-78-2 | NSAID |
| 布洛芬 (Ibuprofen) | 4.4 | Acid | 15687-27-1 | NSAID |
| 萘普生 (Naproxen) | 4.2 | Acid | 22204-53-1 | NSAID |
| 双氯芬酸 (Diclofenac) | 4.0 | Acid | 15307-86-5 | NSAID |
| 对乙酰氨基酚 (Paracetamol) | 9.5 | Zwitterion | 103-90-2 | 酚羟基，弱酸 |
| 阿托伐他汀 (Atorvastatin) | 4.46 | Acid | 134523-00-5 | 他汀类，羧基 |
| 华法林 (Warfarin) | 5.0 | Acid | 81-81-2 | 抗凝药 |
| 青霉素 G (Penicillin G) | 2.76 / 4.84 | Acid | 69-57-8 | β-内酰胺，羧基 |
| 阿莫西林 (Amoxicillin) | 2.4 / 7.4 / 9.6 | Zwitterion | 26787-78-0 | 三 pKa |
| 头孢氨苄 (Cephalexin) | 5.2 / 7.3 | Zwitterion | 15686-71-2 | 两性 |
| 环丙沙星 (Ciprofloxacin) | 6.0 / 8.8 | Zwitterion | 85721-33-1 | 喹诺酮 |
| 普萘洛尔 (Propranolol) | 9.5 | Base | 525-66-6 | β-阻滞剂 |
| 美托洛尔 (Metoprolol) | 9.6 | Base | 37350-58-6 | β-阻滞剂 |
| 阿替洛尔 (Atenolol) | 9.6 | Base | 29122-68-7 | β-阻滞剂 |
| 地西泮 (Diazepam) | 3.4 | Base | 439-14-5 | 苯二氮䓬，弱碱 |
| 苯巴比妥 (Phenobarbital) | 7.4 | Acid | 50-06-6 | 巴比妥类 |
| 卡马西平 (Carbamazepine) | 13.9 | Neutral | 298-46-4 | 中性，不依赖 pH |
| 茶碱 (Theophylline) | 8.6 | Acid | 58-55-9 | 甲基黄嘌呤 |
| 咖啡因 (Caffeine) | 14.0 | Neutral | 58-08-2 | 中性 |
| 雷尼替丁 (Ranitidine) | 2.7 / 8.2 | Base | 66357-35-5 | H₂ 拮抗剂 |
| 奥美拉唑 (Omeprazole) | 4.0 / 8.7 | Zwitterion | 73590-58-6 | 质子泵抑制剂 |
| 二甲双胍 (Metformin) | 2.8 / 11.5 | Base | 657-24-9 | 强碱 |
| 磺胺甲噁唑 (SMX) | 1.6 / 5.7 | Zwitterion | 723-46-6 | 磺胺类 |
| 甲氨蝶呤 (Methotrexate) | 3.8 / 4.8 / 5.5 | Acid | 59-05-2 | 多 pKa |
| 地塞米松 (Dexamethasone) | 12.4 | Neutral | 50-02-2 | 中性甾体 |
| 泼尼松龙 (Prednisolone) | 12.6 | Neutral | 50-24-8 | 中性甾体 |
| 维生素 C (Ascorbic acid) | 4.1 / 11.6 | Acid | 50-81-7 | 烯二醇结构 |
| 盐酸小檗碱 (Berberine) | 11.7 | Base | 633-65-8 | 季铵生物碱 |
| 甘草酸 (Glycyrrhizic acid) | 4.5 | Acid | 1405-86-3 | 三萜皂苷 |
| 黄芩苷 (Baicalin) | 7.0 | Acid | 21967-41-9 | 黄酮苷 |
| 芦丁 (Rutin) | 7.0 / 8.5 | Acid | 153-18-4 | 黄酮醇苷 |
| 盐酸麻黄碱 (Ephedrine HCl) | 9.6 | Base | 50-98-9 | 生物碱盐 |
| 水杨酸 (Salicylic acid) | 2.97 / 13.4 | Acid | 69-72-7 | 邻羟基苯甲酸 |
| 烟酸 (Niacin) | 4.75 | Acid | 59-67-6 | 吡啶羧酸 |
| 组氨酸 (Histidine) | 1.8 / 6.0 / 9.2 | Zwitterion | 71-00-1 | 氨基酸 |
| 赖氨酸 (Lysine) | 2.2 / 9.0 / 10.5 | Base | 56-87-1 | 碱性氨基酸 |
| 谷氨酸 (Glutamic acid) | 2.1 / 4.1 / 9.5 | Acid | 56-86-0 | 酸性氨基酸 |
| 甘氨酸 (Glycine) | 2.3 / 9.6 | Zwitterion | 56-40-6 | 最简单氨基酸 |
| Tris 缓冲液 | 8.06 | Buffer | 77-86-1 | pH 7.0-9.0 常用 |
| MES 缓冲液 | 6.1 | Buffer | 4432-31-9 | Good's 缓冲液 |
| HEPES 缓冲液 | 7.5 | Buffer | 7365-45-9 | Good's 缓冲液 |
| MOPS 缓冲液 | 7.2 | Buffer | 1132-61-2 | Good's 缓冲液 |
| PIPES 缓冲液 | 6.8 | Buffer | 5625-37-6 | Good's 缓冲液 |
Mobile-phase rule of thumb: a compound is ionized within pKa ± 2 (weak reversed-phase retention); pick pH above pKa+2 (acids) or below pKa−2 (bases) to keep it neutral and improve retention.
Common Mobile-Phase Recipes
Classic starting recipes grouped by compound type. Click a card to expand. LC-MS compatibility is flagged.
Recipes are starting points only — adjust for column (C18/C8/Phenyl), polarity and detector. Watch for buffer salt precipitation with organic solvents (try 5% organic as a transition first).