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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
系統開發高效液相層析法:含模式擇、柱化學、流動相與梯度之設計、流量與溫度之優化、檢測器之擇、迭代精調,俾非揮發、熱不穩或極性分析物可分析之。
預期: 規格文件,列分析物及其物化屬性、基質描述、性能標準、等度對梯度之決。
失敗時: pKa 或 logP 闕時,以結構預測工具(ChemAxon、ACD/Labs)估之,或於 C18 柱上 pH 3 與 pH 7 行偵察梯度以經驗評其保留行為。
依分析物屬性擇層析模式與柱。
| 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 |
預期: 柱化學、尺寸、粒徑皆擇定,以分析物屬性為據。
失敗時: 初偵察示 C18 保留差時,換更強保留之固定相(芳香者用苯己基)或他模式(極性者用 HILIC)。
預期: 流動相組成(有機、水、緩衝/添加、pH)與梯度輪廓俱定,偵察運行證分析物於所設窗內洗脫。
失敗時: 選擇性差(梯度優化後分析物仍共洗脫)時,換有機改質劑(ACN 與 MeOH 互換)、pH 調 2 單位、或為帶電分析物加離子對試劑。
預期: 流量與柱溫已優化,背壓於限內,分離度保持或較初始條件改善。
失敗時: 背壓太高時,減流量、升溫、或換寬徑或大粒徑柱。高溫下分離度降時,回 30 C 並受運行較久。
| 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 |
預期: 檢測器已擇並配(波長、增益、採集率),合於分析物化學與靈敏度要求。
失敗時: 所需 LOQ 下 UV 靈敏度不足時,考慮螢光衍生化(如胺之 OPA、胺基酸之 FMOC)或換 LC-MS/MS 以求最大靈敏度與選擇性。
預期: 所有系統適用性標準達;法可分目標分析物與基質干擾及已知降解產物;參數俱錄以供轉移。
失敗時: 迭代調整不解時,考慮根本之別法(換層析模式、2D-LC、衍生化)並回步驟二。
develop-gc-method -- 揮發與半揮發分析物之氣相層析法開發interpret-chromatogram -- 讀並解 HPLC 與 GC 圖譜troubleshoot-separation -- 診斷並修峰形、保留、分離度之病validate-analytical-method -- 所開發 HPLC 法之 ICH Q2 正式驗證