Point Of Care Testing of Ionized Magnesium in Blood with Potentiometric Sensors - Opportunities and Challenges

Abstract

Magnesium assays are being increasingly requested in hospitals and clinical research institutions. The ionized form of magnesium (iMg) is regarded as the biologically active fraction. Ionophore-based potentiometric sensors can determine iMg and apply a selectivity correction for co-existing interfering electrolytes, e.g. Ca 2+ . This technology has been used in several commercial blood analyzers for measuring iMg in whole blood samples. This report reviews the utility of iMg in clinical settings with emphasis on point of care (POC) application, potentiometric Mg 2+ sensor technology and challenges and opportunities for future ionized magnesium assays.

Magnesium in milk

“…The ionised form of magnesium (Mg 2+ ) is regarded as the biologically active form and 117 hence there has been considerable interest in its determination (Zhang, 2011 …”

Ionized or Total Magnesium levels, what should we measure in critical ill patients?

“…Ionized magnesium refers to free magnesium ions and their detection requires laboratory techniques other than those for the total Mg. The availability of magnesium ionselective electrode and specific sensor technology linked with commercial blood analyzers assures more reliable measurement of ionized magnesium in a clinical setting [ 61 ]. This allows specific data collection in clinical practice directly on patients taking into account all those conditions that can alter magnesium levels as: independent factors, interferences with intake, absorption, losses and excretion.…”

Ionized or Total Magnesium Levels, What Should We Measure?

“…Ionized magnesium refers to free magnesium ions, and their detection requires laboratory techniques other than those for the total Mg. The availability of magnesium ion-selective electrode and specific sensor technology linked with commercial blood analyzers makes possible more reliable and widespread ionized magnesium measurements in a clinical setting [61]. Allowing data collection in clinical practice directly on patients considering all those conditions that can alter magnesium levels as independent factors, interfering with intake, absorption, losses, and excretion can create sufficient data to assume reference levels based on the evidence.…”