Department of Physical and Analytical Chemistry, Faculty of Chemistry, University of Oviedo, Oviedo, Spain.
Anal Bioanal Chem. 2011 Nov;401(9):2747-54. doi: 10.1007/s00216-011-5232-8. Epub 2011 Jul 23.
Increased concentrations of circulating metal-degradation products derived from the use of Ti orthopaedic implants may have deleterious biological effects over the long term. Therefore, there is an increasing need to establish the basal level of Ti in the serum of the population (exposed and non-exposed) with appropriate highly sensitive techniques and strategies. With this aim, we have developed a quantitative strategy for the determination of total Ti concentration in human serum samples by isotope dilution analysis using a double-focussing inductively coupled plasma mass spectrometer. Minimizing sample handling and therefore contamination issues, we obtained detection limits of about 0.05 μg L(-1) Ti working at medium resolution (m/Δm 4000). Such extremely good sensitivity permitted us to establish the range of Ti concentration in serum of 40 control individuals (mean 0.26 μg L(-1)) and also to compare it with the level in exposed patients with different Ti metal implants. On the other hand, Ti transport "in vivo" studies have been enabled by online coupling of liquid chromatography (anion-exchange) separation and double-focussing inductively coupled plasma mass spectrometry for sensitive detection of Ti. The development of a postcolumn isotope dilution strategy permitted quantitative characterization of the Ti-transporting biomolecules in human serum. The results for unspiked serum revealed that 99.8% of the Ti present in this fluid is bound to the protein transferrin, with column recoveries greater than 95%.
来自骨科植入物钛的使用所产生的循环金属降解产物浓度的增加，可能会对长期的生物产生有害影响。因此，需要建立一个适用于人群（暴露和非暴露）的基础血清钛浓度，需要用适当的高灵敏度技术和策略来实现。为此，我们已经开发了一种通过使用双聚焦电感耦合等离子体质谱仪进行同位素稀释分析来定量测定人血清样品中总钛浓度的策略。为了尽量减少样品处理和因此产生的污染问题，我们在中等分辨率（m/Δm 4000）下获得了约 0.05μg L(-1) Ti 的检测限。如此高的灵敏度使我们能够确定 40 名对照个体血清中钛浓度范围（平均值 0.26μg L(-1))，并将其与不同钛金属植入物的暴露患者的水平进行比较。另一方面，通过在线连接液相色谱（阴离子交换）分离和双聚焦电感耦合等离子体质谱法，实现了钛的“体内”转运研究，以实现对钛的敏感检测。柱后同位素稀释策略的发展允许对人血清中转运钛的生物分子进行定量表征。对于未加标血清的结果表明，该液体中存在的 99.8%的钛与蛋白转铁蛋白结合，柱回收率大于 95%。
