NIUMAG QMR Series Low-Field NMR Body Composition Analyzer for C57BL/6 Mice

Overview

The NIUMAG QMR Series Low-Field NMR Body Composition Analyzer is a dedicated benchtop instrument engineered for non-invasive, quantitative assessment of body composition in live small laboratory animals—primarily C57BL/6 mice. It operates on the physical principle of low-field nuclear magnetic resonance (LF-NMR), exploiting inherent differences in transverse relaxation times (T₂) among adipose tissue, lean muscle mass, and free/bound water compartments. Unlike destructive endpoint assays (e.g., carcass dissection) or ionizing radiation-based modalities (e.g., DEXA), this system delivers absolute quantification of fat mass, lean mass, and total body water in conscious, unrestrained subjects—without anesthesia, sedation, or surgical intervention. The analyzer employs a permanent magnet with homogeneous field geometry optimized for murine-scale samples, coupled with a purpose-built RF coil tuned to the ¹H Larmor frequency at ~23.5 MHz (0.55 T). Measurement duration per subject is ≤ 90 seconds, enabling high-throughput longitudinal studies under consistent physiological conditions.

Key Features

• Non-destructive, in vivo quantification of fat mass, lean mass, and total body water in awake C57BL/6 mice
• No requirement for anesthesia, fasting, or physical restraint—minimizing stress-induced metabolic confounders
• Permanent magnet architecture ensuring long-term field stability and zero cryogen consumption
• Dedicated mouse-body-composition RF probe with optimized signal-to-noise ratio and spatial homogeneity
• Integrated hardware-software calibration protocol traceable to reference phantoms with known composition
• Robust mechanical design compliant with ISO 13485-aligned manufacturing practices for laboratory instrumentation

Sample Compatibility & Compliance

The QMR Series supports live, conscious specimens across multiple small-animal models: C57BL/6 mice (standard and diet-induced obese strains), BALB/c, ICR, Sprague-Dawley rats (juvenile/adult), and New Zealand White rabbits (≤ 3 kg). All measurements adhere to principles outlined in OECD Test Guideline 452 (Chronic Toxicity Studies) and support GLP-compliant data acquisition workflows. While the instrument itself does not require regulatory certification as an in vitro diagnostic device, its output parameters—including fat mass percentage (%FM), lean mass index (g/cm), and hydration ratio—are compatible with endpoints defined in FDA Guidance for Industry: “Preclinical Assessment of Investigational Drugs for Obesity” (2021) and EMA CHMP Reflection Paper on Animal Models in Obesity Research (2019). Data integrity is maintained via audit-trail-enabled software compliant with ALCOA+ principles.

Software & Data Management

NIUMAG’s proprietary MouseBodyQMR™ software provides full control over pulse sequence selection (CPMG-based multi-echo acquisition), real-time signal processing, and automated T₂ decay fitting using singular value decomposition (SVD) algorithms. Quantitative outputs are exported in CSV and HDF5 formats, supporting direct integration into statistical platforms such as R, Python (SciPy/Pandas), and GraphPad Prism. The software enforces user role-based access control (RBAC), electronic signatures, and 21 CFR Part 11–compliant audit trails—including timestamps for acquisition, analysis, and export events. Raw FID data and processed T₂ distributions are archived with SHA-256 checksum validation to ensure data provenance and reproducibility across multi-site collaborations.

Applications

• Longitudinal monitoring of adiposity dynamics during dietary intervention, genetic manipulation, or pharmacological treatment (e.g., GLP-1 receptor agonists, PPARγ modulators)
• Validation of obesity, insulin resistance, and sarcopenia phenotypes in transgenic and knockout mouse models
• Preclinical evaluation of anti-obesity therapeutics—supporting dose-response characterization and mechanism-of-action studies
• Metabolic phenotyping in circadian rhythm, aging, and gut-microbiome interaction research
• Quality control of breeding colonies through routine body composition screening

FAQ

Is anesthesia required during measurement?
No. The QMR Series is explicitly designed for conscious-animal operation; no sedation or anesthesia is needed.
What is the minimum and maximum animal weight supported?
Validated range: 15–45 g for C57BL/6 mice; up to 500 g for juvenile rats and rabbits (with optional coil adapters).
How is system accuracy verified?
Each unit undergoes factory calibration using NIST-traceable reference phantoms containing triglyceride/water/gelatin matrices mimicking biological T₂ distributions.
Can data be exported for third-party statistical analysis?
Yes—quantitative results and raw time-domain signals are exportable in open, platform-agnostic formats (CSV, HDF5) with metadata tagging.
Does the instrument comply with electromagnetic compatibility (EMC) standards?
Yes—certified to IEC 61326-1:2013 for laboratory equipment EMC requirements and IEC 61000-4 series immunity testing.