CALCIUM, POTASSIUM, ZINC, AND COPPER DETERMINATIONS IN CATARACTOUS HUMAN LENSES

The determination of inorganic ions such as Ca, K, and Na in cataractous lenses has been the subject of several investigations. On the other hand, few studies have been concerned with trace element contents in lenses and with their changes under pathological conditions. Moreover, the data reported are sometimes rather contradictory. The present investigation was carried out to evaluate the presence of Ca, Cu, K, and Zn in human lenses (53 cataractous and 10 clear lenses). Determinations of the elements were performed by atomic absorption spectrometry (both flame and flameless methods) after acid digestion of samples. Compared with results obtained in samples from normal subjects (namely, Ca, 9.9 ± 2.7; Cu, 0.53 ± 0.08; K, 10,306 ± 1232; Zn, 16.5 ± 2.5 mg/kg dry wt), the mean concentration values of cataractous lenses showed significant changes on the basis of the Mann-Whitney test. In fact, sensible increases in concentrations were noted for three of the said elements (Ca, 514 ± 449; Cu, 0.74 ± 0.22; Zn, 24.3 ± 6.0 mg/kg dry wt), whereas K showed a lower concentration (6440 ± 3003 mg/kg dry wt). A positive correlation was found between Zn and Cu concentrations (Y = 0.030X + 0.007, r = 0.79) while an inverse one was valid between Ca and K (Y = -0.097X + 1141, r = 0.65). © 1992.