4,4-dimethyl-4-silapentane-1-ammonium trifluoroacetate (DSA), a promising universal internal standard for NMR-based metabolic profiling studies of biofluids, including blood plasma and serum
4,4-dimethyl-4-silapentane-1-ammonium trifluoroacetate (DSA), a promising universal internal standard for NMR-based metabolic profiling studies of biofluids, including blood plasma and serum
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DOI：
10.1007/s11306-008-0103-9
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发表时间：
2008-06-01
期刊：
影响因子：
3.6
通讯作者：
Connor, Susan C.
中科院分区：
文献类型：
--
作者：
Alum, Mohammed F.;Shaw, Paul A.;Connor, Susan C.
基于核磁共振(NMR)的生物体液和组织代谢谱分析对于促进疾病、药物疗效和毒性研究的生物标记物的发现具有重要意义。尿液和血浆/血清是最受关注的生物流体，因为它们在临床和临床前研究中都是最容易获得的。然而，蛋白质流体，如血清或血浆，是最大的技术挑战，因为目前用于水基核磁共振样品的内标的化学位移(增量)和线宽(nu(1/2))很大程度上受到蛋白质结合的影响。因此，我们研究了4，4-二甲基-4-硅戊烷-1-三氟乙酸铵(DSA)作为生物体液通用内标物的适用性。用质子(H-1)核磁共振波谱测定了血清pH值(3、7.4和10)和DSA浓度对DSA三甲基硅基共振的整体线形和位置的影响。并与3-三甲基硅基丙酸钠盐(TSP)的测定结果进行了比较。DSA峰的化学位移和线宽都不受pH和DSA浓度的影响，而TSP的这些参数由于蛋白质结合而表现出较大的变化。此外，在所有pH条件下，DSA的峰面积与其浓度呈线性相关，而与TSP的相关性不明显。总体而言，与TSP相比，这些结果支持将DSA用作生物体液的准确通用内部化学位移参考和浓度/归一化标准。对于蛋白质生物流体，如血清，目前没有可用的标准，这为操作员和光谱仪节省了相当多的时间。
Nuclear magnetic resonance (NMR)-based metabolic profiling of biofluids and tissues are of key interest to enhance biomarker discovery for disease, drug efficacy and toxicity studies. Urine and blood plasma/serum are the biofluids of most interest as they are the most accessible in both clinical and preclinical studies. However, proteinaceous fluids, such as blood serum or plasma, represent the greatest technical challenge since the chemical shift (delta) and line-width (nu(1/2)) of internal standards currently used for aqueous NMR samples are greatly affected by protein binding. We have therefore investigated the suitability of 4,4-dimethyl-4-silapentane-1-ammonium trifluoroacetate (DSA) as a universal internal standard for biofluids. Proton (H-1) NMR spectroscopy was used to determine the effect of serum pH (3, 7.4 and 10) and DSA concentration on the overall lineshape and position of the trimethylsilyl resonance of DSA. The results were compared to that of 3-(trimethylsilyl)propionic acid sodium salt (TSP). Both the chemical shift and line-width of the DSA peak were not significantly affected by pH or DSA concentration, whereas these parameters for TSP showed large variations due to protein binding. Furthermore, the peak area of DSA correlated linearly with its concentration under all pH conditions, whilst no linear correlation was observed with TSP. Overall, in contrast to TSP, these results support the use of DSA as an accurate universal internal chemical shift reference and concentration/normalisation standard for biofluids. In the case of proteinaceous biofluids such as serum, where no current standard is available, this offers a considerable saving in both operator and spectrometer time.