Which chemical forms a thermostable bond with calcium, causing chemical interference in atomic absorption?

The chemical that forms a thermostable bond with calcium, leading to chemical interference in atomic absorption, is phosphate. In the context of atomic absorption spectroscopy, the presence of phosphate can significantly impact the measurements of calcium levels because it binds to calcium ions, reducing the free calcium available for absorption analysis. This binding alters the equilibrium of calcium concentration in the sample, creating a challenge when trying to accurately determine calcium levels through atomic absorption techniques.

Phosphate’s ability to create a strong bond with calcium ions means that it can form complexes that remain stable under high-temperature conditions typically used in atomic absorption processes. This stability makes it particularly problematic because it can obscure or misrepresent the true concentration of calcium in the sample, leading to erroneous results.

Understanding this interaction is crucial for interpreting results in clinical chemistry, especially when assessing calcium levels, as it underscores the need for careful consideration of interfering substances like phosphate in analytical procedures.