毛细管SDS无胶筛分电泳测定小分子多肽相对分子质量

目的建立快速毛细管SDS无胶筛分电泳法(SDS-NGS),测定小分子多肽相对分子质量。方法涂层毛细管(管长30cm,内径100μm);分离电压为9kV(300V/cm),分离温度为20℃;检测波长为214nm,检测时间为18min;所用SDS-多肽相对分子质量标准范围为2 512~16 949;以橙G(OG)为内标参照物。结果在相对分子质量2512~16949范围内,多肽相对分子质量的对数与其相对迁移率具有良好的线性关系(r=0.996);应用该方法测定了重组人奈西立肽、重组人表皮生长因子、虎纹镇痛肽、重组人心钠肽4种重组小分子多肽的相对分子质量,所测结果变异系数CV均小于3%。结论毛细管SDS无胶筛分电泳方便快速,灵敏度高,重现性好,结果准确,可作为小分子多肽相对分子质量的检测方法。

Determination of Relative Molecular Mass of Small Polypeptide by Capillary SDS Non-gel Sieve Electrophoresis

Objective To develop a capillary SDS non-gel sieve electrophoresis for rapid determination of relative molecular mass of small polypeptide.Methods Determine the relative molecular mass of small polypeptide by capillary SDS non-gel sieve(electrophoresis) using orange G(OG) as internal reference under the following condition:coated capillary(length 30 cm,internal diameter 100 μm);separation voltage 9 kV(300 V/cm);separation temperature 20℃;detection wavelength 214 nm;detection time 18 min;SDS-polypeptide marker(Mr 2 512-16 949).Results The relative molecular mass at a range of 2 512-16 949 showed a good linear relationship to the migration rate of polypeptide(r=0.996).The relative molecular masses of 4 kinds of small polypeptides,i.e.recombinant human B type natriuretic peptide(rhBNP),recombinant human epidermal growth factor(rhEGF),Huwen analgesic peptide(HWAP-1) and recombinant human atrial natriuretic peptide(rhANP),showed a variation coefficient of less than 3%.Conclusion(Capillary) SDS non-gel sieve electrophoresis was simple,rapid,accurate and of good repeatability.It might be used for the determination of relative molecular mass of small polypeptide.