Simple Spectrophotometric Sequential Injection Analysis System for Determination of Serum Calcium

Abstract

A sequential injection analysis (SIA) system for the determination of total calcium in blood has been implemented. The assay principle is based on the arsenazo III method, in which the indicator’s complex with calcium forms a blue-purple colour. The absorbance peak height at 650 nm was proportional to the calcium content in samples. A linear range was obtained from 2.5 - 15 mg?dL–1 (r2 = 0.999), with a detection limit of 0.430 mg?dL–1 (3σ). Magnesium, glucose, hae-moglobin, and bilirubin at 123, 1,000, 50, and 0.5 mg?dL–1, respectively, were not found to interfere with the proposed system significantly (recovery 99.1% - 104.4%). The sampling frequency was 30 h–1, in which the carry-over effect was negligible (0.69%). The proposed SIA system was successfully applied to the determination of calcium from serum samples (r2 = 0.970; n = 30)

Development of a Paper-Based Analytical Method for the Colorimetric Determination of Calcium in Saliva Samples

“…Analytical methods such as complexometric titrations [ 14 , 15 ], fluorometric titrations [ 16 , 17 ], and spectrophotometric determination [ 18 ] have been used since the 1950s. Many instrumental analytical methods have been developed for the determination of calcium in a big variety of samples, utilizing various detection techniques, such as flame atomic absorption spectroscopy (FAAS) [ 19 , 20 , 21 ], atomic emission spectrometry [ 22 ], inductively coupled plasma mass spectrometry (ICP-MS) [ 23 , 24 , 25 , 26 ], fluorescence [ 27 , 28 ], ion chromatography [ 29 ] UV–Vis spectrophotometry [ 30 ], and flow injection [ 31 , 32 ].…”