Department of Chemistry, Institute of Biomedical Sciences and Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials, Fudan University, Shanghai 200433, PR China.
Langmuir. 2010 May 18;26(10):7444-50. doi: 10.1021/la9041698.
The analysis of peptides by the mass spectrometry (MS) technique is important in modern life science. The enrichment of peptides can increase the detection efficiency and is sometimes indispensable for collecting the information on proteins with low-abundance. Herein, we first report that functionalized periodic mesoporous organosilica (PMO) materials have a superior peptide enrichment property. It is demonstrated that the PMO materials with an organo-bridged (-CH(2)-) hybrid wall composition display a highly enhanced peptide enrichment ability compared to the pure silica material (SBA-15) with similar mesostructured parameters and morphology. More importantly, by surface modification of PMO with amino groups (denoted NH(2)-PMO), PMO and NH(2)-PMO with opposite charged surfaces (-25.2 and +39.0 mV, respectively) show selective affinities for positively and negatively charged peptides, respectively. By directly adding PMO, NH(2)-PMO as well as pure silica materials to the peptides solution with a low concentration (1-2 fmol/microL), 36 and 28 peptides can be detected from the BSA digestion in the presence of PMO and NH(2)-PMO, respectively, while only 6 and 4 are monitored in the case of SBA-15 enrichment and from solution without enrichment, respectively. Moreover, 69.4% (25 of 36) of enriched peptides by PMO have pI > or = 6 and 80% (21 of 28) of enriched peptides by NH(2)-PMO possess pI < or = 6. Combining the results from the NH(2)-PMO and PMO enrichment together, 51 peptides can be identified with a MOWSE score of 333. It is also noted that similar conclusions can also be obtained from the peptides solution originated from other proteins. This might be an important contribution to the understanding of the interaction between peptides and porous hosts, and the proposed method is promising for the development of both material science and biotechnology.
基于质谱（MS）技术的肽分析在现代生命科学中具有重要意义。肽的富集可以提高检测效率，并且对于收集低丰度蛋白质的信息有时是必不可少的。在此，我们首次报道功能化介孔有机硅（PMO）材料具有优越的肽富集性能。结果表明，与具有相似介孔结构参数和形态的纯硅材料（SBA-15）相比，具有有机桥接（-CH(2)-）杂化壁组成的 PMO 材料具有更高的肽富集能力。更重要的是，通过 PMO 的氨基表面改性（记为 NH(2)-PMO），PMO 和具有相反电荷表面的 NH(2)-PMO（分别为-25.2 和 +39.0 mV）分别对带正电荷和带负电荷的肽显示出选择性亲和力。通过直接将 PMO、NH(2)-PMO 和纯硅材料添加到低浓度（1-2 fmol/μL）的肽溶液中，在 PMO 和 NH(2)-PMO 的存在下，可以从 BSA 消化产物中检测到 36 和 28 种肽，而在 SBA-15 富集和无富集的情况下，分别监测到 6 和 4 种肽。此外，通过 PMO 富集的肽中有 69.4%（25 个中的 25 个）具有 pI > 或 = 6，通过 NH(2)-PMO 富集的肽中有 80%（28 个中的 21 个）具有 pI < 或 = 6。将 NH(2)-PMO 和 PMO 富集的结果结合起来，可以鉴定出 51 种肽，其 MOWSE 得分达到 333。还注意到，从其他蛋白质来源的肽溶液中也可以得到类似的结论。这可能是对肽与多孔宿主相互作用的理解的重要贡献，并且所提出的方法有望为材料科学和生物技术的发展做出贡献。
