Flame Photometric Determination of Calcium, Strontium, and Barium in Mixture

Abstract

consistent retention of trichloroacetic acid by dried precipitates of proteins, although some of the series (TableI, columns 7 and 8; Table II, No. 3) show mean minimum weights approximately 4 to 8% in excess of the amounts of protein determined by direct drying or by spectrophotometric methods.Gravimetric determination of proteins dried without other treatment at temperatures between 80°and 110°C. has been reported (3, 5-7, 18-20, 24)', such weights have been stated to represent anhydrous weights of proteins (3, 5, 6). It is possible that residual water may lead to errors in the estimation of dry weights of proteins. The weights obtained in these studies after precipitation of proteins with trichloroacetic acid are consistent and reproducible and may represent anhydrous weights; however, no attempt has been made to investigate the dried residues for content of water.

Roles of glycogen synthase kinase 3 alpha and calcineurin in regulating the ability of sperm to fertilize eggs

“…Standards were prepared by dissolving calcium chloride in 0.7% v/v TCA in RO filtered water. Calcium in the samples and standards were measured using Flame Photometry (Optima 8x00 ICP‐OES, PerkinElmer, MA, USA) . Calcium levels are reported as ng/10 8 sperm cells.…”

“…27 Calcium levels are reported as ng/10 8 sperm cells. Sperm suspensions on ice were sonicated twice at amplitude of 60% for 10 seconds each.…”

“…Calcium in the samples and standards were measured using Flame Photometry (Optima 8x00 ICP-OES, PerkinElmer, MA, USA). 27 Calcium levels are reported as ng/10 8 sperm cells.…”

A simple flame-photometer of high sensitivity

“…Several papers deal with the interference problems [13,14] of various alkaline determinations, mostly with the interference of two components [1,2] etc.…”

“…/1. Hegedª T. Millner and E. Pungor [ 14] describe methods for the flame-photometer analysis of barium, strontium and calcium mixtures.…”