In response to concerns over the degradation of titanium implants, researchers from the University of Oviedo in Spain have developed a highly sensitive method to determine the levels of titanium in human blood (Analytical and Bioanalytical Chemistry, July 22, 2011).
Titanium implants are routinely used for bone fractures and dental work, and it has been shown that titanium-based implants both corrode and degrade, generating metallic debris, according to the researchers. There is some concern over the increased concentrations of circulating metal-degradation products derived from these implants and their potential harmful biological effects over a period of time, including hepatic injury and renal lesions.
To assess the implications of these leaks, it is essential to accurately measure the basal, normal levels of titanium in the bloodstream and to quantify how much higher levels are in patients with implants, the researchers noted.
They collected blood from 40 healthy individuals and 37 patients with titanium implants -- 15 with tibia implants, eight with femur implants, and 14 with humerus implants. They then used isotope dilution analysis and mass spectrometry to analyze the blood samples.
They found that control individuals had very low levels of titanium in the blood, whereas titanium concentrations were significantly higher for all the patients with implants. The sensitivity of the method was such that the researchers were also able to show significant differences in titanium levels for different types of bone fixation devices. The more invasive implants shed more metallic debris into the blood than the external, superficial designs, according to the researchers.
This study also identified how the titanium from the implants is transported in the bloodstream and potentially distributed and accumulated.
"The simplicity of the methodology based on isotope dilution analysis and the accuracy and precision of the obtained results should encourage the use of the proposed strategy on a routine basis," the researchers concluded.