Edwards F M, Kraushaar J J, Ristinen R A, Rudolph H
Med Phys. 1977 Jan-Feb;4(1):58-65. doi: 10.1118/1.594303.
The use of the stable isotope 48Ca as a tracer in biological systems has been studied. Determination of 48Ca concentrations in samples was accomplished by proton activation via the (p,n) reaction with subsequent measurement of gamma-ray spectra from 44-h 48Sc and 4-h 44Sc. With protons of about 5.5 MeV and a Ge(Li) gamma-ray detector, and with no chemical processing of the samples, ratios of these two radioisotopes can be determined with sufficient precision to allow 48Ca tracer studies to be performed with sensitivity at least equivalent to that possible with the common 45Ca radioactive tracer.
已对稳定同位素48Ca作为生物系统示踪剂的用途进行了研究。通过质子活化经由（p，n）反应并随后测量来自44小时48Sc和4小时44Sc的伽马射线光谱来完成样品中48Ca浓度的测定。使用约5.5 MeV的质子和锗锂伽马射线探测器，并且不对样品进行化学处理，就可以足够精确地测定这两种放射性同位素的比率，从而能够以至少与常用的45Ca放射性示踪剂相当的灵敏度进行48Ca示踪剂研究。
