Spectroscopic Analysis of Calcium Oxalate Kidney Stone Inhibition by Nordihydroguaiaretic Acid (NDGA)

This current study provides information regarding the inhibition of calcium oxalate type of kidney stones by the use of nordihydroguaiaretic acid (NDGA). Around 80% of kidney stones found in patients are principally made of calcium oxalate and calcium phosphate. NDGA is an antioxidant compound that is chemically extracted from the desert bush Larrea tridentata. This work is a logical continuation of a previous research, where different concentrations of Larrea tridentata extract were used for such inhibition. Size and morphological changes from a calcium oxalate monohydrate (COM) structure to a calcium oxalate dihydrate (COD) structure were previously reported. In the current research, synthetically grown calcium oxalate crystals with and without NDGA are analyzed by Raman and Fourier transformed infrared absorption spectroscopies. The Raman results show that the presence of NDGA has no contribution to previously observed morphological changes, but its presence affects the strength and bond between carbon atoms. The presence of a strong absorption line in infrared spectrum reveals the existence of NDGA in a sample