Question 1

What is the Meaning of Isotope Dilution?

Accepted Answer

Isotope Dilution is an analytical method to quantify a substance by introducing a known amount of its isotopically labeled counterpart. This technique relies on complete mixing of the added labeled substance with the unlabeled substance present, enabling precise measurement of the original analyte concentration based on the change in isotopic ratio.

Question 2

What is the Context of Isotope Dilution?

Accepted Answer

Within biological systems, Isotope Dilution assesses dynamic processes not easily measured directly. It applies in endocrinology and metabolism to study production, secretion, and clearance rates of hormones, nutrients, and biomolecules. This is especially useful when substances are at low concentrations or when synthesis and breakdown occur concurrently.

Question 3

What is the Significance of Isotope Dilution?

Accepted Answer

Clinically, Isotope Dilution provides exceptional accuracy for determining endogenous hormone production and metabolic flux, critical for diagnosing and managing complex endocrine conditions. This precision assists in differentiating between overproduction and impaired clearance, directly informing therapeutic strategies and improving patient health outcomes.

Question 4

What is the Mechanism of Isotope Dilution?

Accepted Answer

A known, precise quantity of a stable or radioactive isotope of the compound is introduced into the biological system. After uniform mixing, a sample is collected. The isotopic ratio of labeled to unlabeled compound is determined using advanced analytical techniques, allowing calculation of the original concentration or total pool size.

Question 5

What is the Application of Isotope Dilution?

Accepted Answer

In clinical practice, Isotope Dilution measures physiological parameters such as cortisol secretion rates, growth hormone production, or glucose turnover. It also aids in determining total body water and lean body mass, providing objective nutritional assessments. This method is vital for research and obtaining highly accurate physiological data.

Question 6

What is the Metric of Isotope Dilution?

Accepted Answer

Quantitative assessment in Isotope Dilution studies primarily uses mass spectrometry (GC-MS or LC-MS) to measure stable isotope ratios. For radioisotopes, methods like scintillation counting or gamma spectrometry are employed. These platforms provide sensitive and specific data for accurate analyte calculation.

Question 7

What is the Risk of Isotope Dilution?

Accepted Answer

Stable isotope dilution methods carry minimal risk, mainly from intravenous administration. Radioactive isotope applications involve low-dose radiation, requiring strict safety guidelines and careful patient selection. Clinical risks include inaccurate results from incomplete equilibration, sample contamination, or analytical errors, potentially leading to misinterpretation of data and inappropriate clinical decisions.

Isotope Dilution

Meaning

Context

Significance

Mechanism

Application

Metric

Risk

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