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You MUST use this before any creative work - creating features, building components, adding functionality, modifying behavior, or planning anything new, in software or out of it (a talk, a business, a renovation).
develop-hplc-methodDevelop a high-performance liquid chromatography method: define separation goals, select column chemistry and mobile phase, optimize gradient and flow conditions, choose the appropriate detector, and evaluate initial method performance for target analytes in solution or complex matrices.
Independent GitHub snapshot · Automated classification · Original documentation governs
系統發展高效液相色譜法:擇模式、柱、流動相與梯度、流速溫度之優化、檢測器之擇、及為不揮發、熱不穩或極性分析物之迭代精化。
得: 規格文檔列分析物及理化性、基質述、性能準則、等度或梯度之定。
敗則: pKa 或 logP 未知則由結構以預測工具(ChemAxon、ACD/Labs)估之,或於 pH 3 與 pH 7 之 C18 柱上行掃描梯度以經驗評保留行為。
依分析物之性擇色譜模式與柱。
| Mode | Column Chemistry | Mobile Phase | Best For |
|---|---|---|---|
| Reversed-phase (RP) | C18 (ODS) | Water/ACN or water/MeOH + acid/buffer | Non-polar to moderately polar, most small molecules |
| RP (extended) | C8, phenyl-hexyl, biphenyl | Water/organic + modifier | Shape selectivity, aromatic compounds, positional isomers |
| RP (polar-embedded) | Amide-C18, polar-endcapped C18 | Water/organic, compatible with high aqueous | Polar analytes that elute too early on standard C18 |
| HILIC | Bare silica, amide, zwitterionic | High organic (80-95% ACN) + aqueous buffer | Very polar, hydrophilic compounds (sugars, amino acids, nucleotides) |
| Ion-exchange (IEX) | SAX or SCX | Buffer with ionic strength gradient | Permanently charged species, proteins, oligonucleotides |
| Size-exclusion (SEC) | Diol-bonded silica, polymer | Isocratic aqueous or organic buffer | Protein aggregates, polymers, molecular weight distribution |
| Chiral | Polysaccharide (amylose/cellulose) | Normal-phase or polar organic mode | Enantiomeric separations, chiral purity |
得: 柱化學、尺寸、粒徑已擇且有理,依分析物之性。
敗則: 初掃描示 C18 保留差則換更強保留相(芳香物用 phenyl-hexyl)或他模式(極性物用 HILIC)。
得: 流動相組成(有機、水、緩衝/添加、pH)與梯度剖面已定,掃描證分析物於所設窗內洗脫。
敗則: 選擇性差(雖調梯度諸分析物仍共洗脫)則換有機改性劑(ACN 至 MeOH 或反之)、調 pH 二單位,或為帶電分析物加離子對試劑。
得: 流速與柱溫已優化,背壓在限內,分離較初始條件保或改。
敗則: 背壓過高則減流速、升溫,或換更寬或大粒徑柱。高溫下分離退化則返 30 C 且接更長運行時。
| Detector | Principle | Sensitivity | Selectivity | Key Considerations |
|---|---|---|---|---|
| UV (single wavelength) | Absorbance at fixed lambda | ng range | Compounds with chromophores | Simple, robust, most common |
| DAD (diode array) | Full UV-Vis spectrum | ng range | Chromophores + spectral ID | Peak purity assessment, library matching |
| Fluorescence (FLD) | Excitation/emission | pg range (10-100x more sensitive than UV) | Native fluorophores or derivatized | Excellent selectivity, requires fluorescent analytes |
| Refractive index (RI) | Bulk property | ug range | Universal (no chromophore needed) | Temperature-sensitive, gradient-incompatible |
| Evaporative light scattering (ELSD) | Nebulization + light scattering | ng range | Universal, non-volatile analytes | Semi-quantitative, non-linear response |
| Charged aerosol (CAD) | Nebulization + corona discharge | ng range | Universal, non-volatile analytes | More uniform response than ELSD |
| Mass spectrometry (MS) | m/z detection | pg-fg range | Structural, highest selectivity | Requires MS-compatible mobile phases |
得: 檢測器已擇且配(波長、增益、採集率)合分析物化學與靈敏度之要。
敗則: UV 靈敏度於所需 LOQ 不足則考熒光衍生化(如胺用 OPA、氨基酸用 FMOC)或換 LC-MS/MS 以得最大靈敏度與選擇性。
得: 諸系統適用性準則合;法能將目標分析物與基質干擾及已知降解物分開;參已書以待轉移。
敗則: 迭代調未解則考根本不同之法(換色譜模式、2D-LC 或衍生化)並返第二步。
develop-gc-method — 為揮發與半揮發分析物發展氣相色譜法interpret-chromatogram — 讀並釋 HPLC 與 GC 色譜圖troubleshoot-separation — 診並修峰形、保留、分離之問題validate-analytical-method — 所發 HPLC 法之正式 ICH Q2 驗證