Inositol Analysis by HPLC and Its Stability in Scavenged Sample Conditions

Area of Science:

• Biochemistry
• Neonatology
• Clinical Chemistry

Background:

• Inositol is a sugar alcohol crucial for fetal development, with concentrations decreasing as gestational age advances.
• Limited studies suggest inositol may reduce retinopathy of prematurity and chronic lung disease in premature infants.
• Inositol's pharmacokinetics in premature newborns require further investigation, particularly concerning gestational age, postnatal age, and feeding.

Purpose of the Study:

• To develop and validate a high-pressure liquid chromatographic (HPLC) assay for quantifying inositol in human plasma.
• To assess the stability of inositol in human plasma under various storage conditions relevant to clinical laboratories.
• To determine the feasibility of using archived plasma samples for studying inositol concentrations in preterm newborns.

Main Methods:

• Development of a novel HPLC assay for inositol with a linear range of 0–1000 μM and a lower limit of quantitation of 50 μM.
• Inositol stability testing in human plasma stored under refrigeration and at room temperature for up to 14 days.
• Evaluation of inositol stability in the presence of intact or lysed red blood cells and common anticoagulants.

Main Results:

• The developed HPLC assay is sensitive and accurate for inositol quantification.
• Inositol in human plasma demonstrated stability for up to 14 days when stored at refrigeration or room temperature.
• Plasma inositol stability was unaffected by storage with red blood cells or common anticoagulants.

Conclusions:

• The novel HPLC method provides a reliable means for measuring inositol concentrations.
• Inositol is stable in archived human plasma for up to 14 days under typical clinical laboratory storage conditions.
• This stability facilitates retrospective studies on inositol levels in preterm infants, minimizing the need for additional sample collection and associated trauma.