A methodology study for sodium quantification in bone and soft tissue based on in vivo neutron activation analysis...

Area of Science:

• Nuclear Physics
• Human Physiology
• Biomedical Engineering

Background:

• Sodium (Na) is vital for health, but excess intake is linked to diseases.
• Sodium is stored in soft tissues and bone, with distinct exchange rates.
• Conventional methods cannot measure sodium in specific body compartments like bone and soft tissue.

Purpose of the Study:

• To develop and apply a transportable neutron generator-based in vivo neutron activation analysis (NAA) technique.
• To quantify sodium concentration separately in bone and soft tissue.
• To investigate the impact of dietary sodium intake on sodium storage and metabolism.

Main Methods:

• Utilized a portable neutron generator for in vivo NAA on pig legs.
• Employed a high-purity germanium detector to measure gamma rays from neutron-activated sodium.
• Developed a biokinetic model incorporating internal dosimetry to determine sodium concentration and retention half-life in bone and soft tissue.

Main Results:

• Pigs fed a high-sodium diet showed significantly higher soft tissue sodium concentration (1057.08±43.62 ppm) compared to those on a low-sodium diet (704.46±45.60 ppm, p=0.007).
• Bone sodium concentration was not significantly affected by dietary sodium intervention (856.45±78.48 ppm vs. 803.30±48.98 ppm, p=0.107).

Conclusions:

• The developed in vivo NAA method effectively measures altered sodium levels due to dietary intake.
• This technique has significant potential for studying the relationship between sodium consumption and health outcomes like hypertension.
• Dietary sodium primarily impacts soft tissue sodium storage, with minimal effect on bone sodium concentration.