Nowak Christine, Ponniah Gomathinayagam, Cheng Guilong, Kita Adriana, Neill Alyssa, Kori Yekaterina, Liu Hongcheng
Product Characterization, Alexion Pharmaceuticals, Cheshire, CT 06410, USA.
Product Characterization, Alexion Pharmaceuticals, Cheshire, CT 06410, USA.
Anal Biochem. 2016 Mar 1;496:4-8. doi: 10.1016/j.ab.2015.12.004. Epub 2015 Dec 21.
Light exposure is one of several conditions used to study the degradation pathways of recombinant monoclonal antibodies. Tryptophan is of particular interest among the 20 amino acids because it is the most photosensitive. Tryptophan degradation forms several products, including an even stronger photosensitizer and several reactive oxygen species. The current study reports a specific peptide mapping procedure to monitor tryptophan degradation. Instead of monitoring peptides using UV 214 nm, fluorescence detection with an excitation wavelength of 295 nm and an emission wavelength of 350 nm was used to enable specific detection of tryptophan-containing peptides. Peaks that decreased in area over time are likely to contain susceptible tryptophan residues. This observation can allow further liquid chromatography-mass spectrometry (LC-MS) analysis to focus only on those peaks to confirm tryptophan degradation products. After confirmation of tryptophan degradation, susceptibility of tryptophan residues can be compared based on the peak area decrease.
光照是用于研究重组单克隆抗体降解途径的几种条件之一。在20种氨基酸中，色氨酸特别受关注，因为它是最易感光的。色氨酸降解会形成多种产物，包括一种更强的光敏剂和几种活性氧物种。当前的研究报告了一种用于监测色氨酸降解的特定肽图谱分析方法。不是使用214 nm紫外光监测肽段，而是采用激发波长为295 nm、发射波长为350 nm的荧光检测，以实现对含色氨酸肽段的特异性检测。随着时间推移面积减小的峰可能含有易降解的色氨酸残基。这一观察结果可使进一步的液相色谱-质谱联用（LC-MS）分析仅聚焦于那些峰，以确认色氨酸降解产物。在确认色氨酸降解后，可根据峰面积减小情况比较色氨酸残基的易感性。
