Chromium51EDTAChecker

Utility description: Chromium-51 EDTA

Chromium-51 EDTA Quality Checker — Chromium-51 EDTA for GFR assessment

ℹ️  Utility checks critical parameters of chromium-51 EDTA:
    • Radiochemical purity (≥95%) — fraction of Cr-51 bound to EDTA
    • Free chromium-51 (≤5%) — unreacted chromium, accumulates in liver/spleen
    • pH (4.0–7.0) — critical for complex stability and safety
    • Sterility and apyrogenicity (endotoxins ≤175 EU/vial)
    • Appearance (clarity, absence of particles)
    • Stability control considering Cr-51 half-life (27.7 days)

⚠️  CRITICAL: 
    • Free chromium-51 >5% → accumulation in liver and spleen, distorted GFR results!
    • Radiochemical purity <95% → unreliable kidney function assessment!
    • Preparation age >48 hours → risk of complex degradation!

Usage:
  Chromium51EDTAChecker.exe                            → demo mode (console output)
  Chromium51EDTAChecker.exe input.csv output.json      → evaluate your data

Input format:
BatchNumber,ActivityMBqPerML,RadiochemicalPurityPercent,FreeChromiumPercent,pH,EndotoxinsEU,SterilityTest,Appearance,PreparationDate

Example (sterility: 0=sterile, 1=contaminated; appearance: 0=clear, 1=turbid):
  CR51-EDTA-2026-001,50.0,98.5,1.2,6.5,10.0,0,0,2026-05-20

Supported product types:
• Standard — standard solution for injection
• Kit — kit for ex tempore preparation

— WHY IS THIS NEEDED?
Chromium-51 EDTA is the "gold standard" for measuring GFR (glomerular filtration rate):
• 27.7-day half-life — convenient for logistics and multi-day studies
• Gamma emission (320 keV) — optimal for gamma camera detection
• Cr-51-EDTA complex is not metabolized, freely filtered in kidney glomeruli, and not secreted by tubules
• Used in suspected renal failure, before nephrotoxic chemotherapy, for dosing renally-excreted drugs

⚠️  CRITICAL:
• Radiochemical purity ≥95% — ensures that filtration of the complex, not free chromium, is measured
• Free chromium ≤5% — free Cr-51 binds to plasma proteins and accumulates in the reticuloendothelial system (liver, spleen), leading to underestimation of calculated GFR
• pH 4.0–7.0 — outside this range, the complex may degrade or cause phlebitis
• Sterility and endotoxins — mandatory for intravenous administration
• Appearance — solution must be clear, particle-free
• Stability — preparation is usable within 24–48 hours after preparation when stored refrigerated (2–8°C)

Key features:
• Radiochemical purity check (main quality parameter)
• Free chromium-51 control (critical impurity)
• Stability assessment based on preparation date (considering T½=27.7 days)
• Activity correction factor calculation for time of administration
• Physicochemical parameter checks (pH, sterility, endotoxins, appearance)

Critical parameters:
• Radiochemical purity: ≥95.0%
• Free chromium-51: ≤5.0%
• pH: 4.0–7.0
• Endotoxins: ≤175 EU/vial (or ≤5 EU/kg body weight)
• Sterility: no microbial growth
• Appearance: clear colorless solution
• Stability: ≤48 hours after preparation

💡 Usage tips:
1. Radiochemical purity controlled by thin-layer chromatography (TLC) or HPLC
2. For TLC use: Whatman No.1 paper, eluent — acetone/water (9:1). Rf Cr-51-EDTA ≈ 0.0, Rf free Cr-51 ≈ 0.8–1.0
3. Preparation is stable for 24–48 hours after preparation when stored refrigerated (2–8°C)
4. Activity is corrected to time of administration considering 27.7-day half-life
5. If free chromium >5% detected — batch rejected (GFR results will be inaccurate)!
6. Turbidity or presence of particles — absolute contraindication for administration!

⚠️ Note: Chromium-51 EDTA is the reference method for GFR measurement. Any deviation in radiochemical purity directly affects the accuracy of kidney function diagnosis. Free chromium creates background activity in the liver and spleen, interfering with correct clearance calculation.