ETH 4030, also known as Magnesium Ionophore III, is primarily used in the field of analytical chemistry for the selective detection and measurement of magnesium ions (Mg²⁺) in various samples. Its application is particularly significant in the development of ion-selective electrodes (ISEs), which are essential tools for quantifying magnesium levels in biological, environmental, and industrial contexts.

In biological research, ETH 4030 is utilized to study magnesium's role in cellular processes, such as enzyme activation, signal transduction, and muscle contraction. It helps researchers monitor magnesium dynamics in living cells or tissues, providing insights into its physiological and pathological significance.

In environmental science, this ionophore is employed to assess magnesium concentrations in water bodies, soil, and other environmental samples, aiding in pollution monitoring and resource management.

Additionally, ETH 4030 finds use in industrial applications, where precise magnesium measurement is critical, such as in the quality control of pharmaceuticals, food products, and manufacturing processes. Its high selectivity for magnesium ions ensures accurate and reliable results in these diverse applications.