Analytical methods for quantitating sulfate in plasma and serum

Abstract

Circulating sulfate needs to be maintained at sufficiently high levels for healthy growth and development. Animal studies have shown the adverse physiological consequences of low circulating sulfate level on the skeletal, neurological and reproductive systems. However, sulfate is not routinely measured in clinical investigations, despite the importance of sulfate being documented over the past several decades. Several methods have been developed for measuring serum and plasma sulfate level in animals and humans, including a range of barium sulfate precipitation techniques that have been a major focus of sulfate analytics since the 1960s. Evaluation of an ion chromatography method demonstrated its utility for investigation of sulfate levels in human health. More recently, liquid chromatography-tandem mass spectrometry has been used to show hyposulfatemia in a human case of mild skeletal dysplasia. This article provides an overview of analytical methods for measuring sulfate in serum and plasma, highlighting the strengths and limitations of each method.

Keywords: Assay; Biochemical pathology; Method; Sulfataemia; Sulfate.

Figure 1. The number of articles published in the field of circulating inorganic sulfate level

Articles were identified in PubMed 7 January 2024 using the search term (inorganic) AND ((sulfate) OR (sulphate)) AND ((blood) OR (plasma) OR (serum)). The increasing number of articles in recent years reflects the current interest in the physiological importance of circulating sulfate level in mammalian physiology.

Figure 2. Inorganic sulfate levels in plasma and serum

(A) Animal [2,3,15,19,20] and (B) human [2,13,15–19,21–32] plasma (filled symbols) and serum (unfilled symbols) levels (average of each study) determined using the methods shown at the bottom (matching symbols for panels A and B).