Technetium99mPyrophosphateChecker

URS & FS — User Requirements and Functional Specification

This document describes the controlled interface and behaviour of Technetium99mPyrophosphateChecker for Tc-99m PYP.

Domain limits and critical parameters

• ℹ️ Utility checks critical parameters of Tc-99m PYP:
• • Radiochemical purity (≥95%)
• • Free pertechnetate (≤5%)
• • Colloidal technetium (≤5%)
• • Aluminum content (≤10 ppm) — CRITICAL!
• • pH, endotoxins, sterility
• ⚠️ CRITICAL: Aluminum breakthrough from generator (>10 ppm) leads to colloid formation.
• BatchNumber,TotalActivityMBq,RadiochemicalPurityPercent,FreePertechnetatePercent,ReducedHydrolyzedTcPercent,pH,EndotoxinsEU,SterilityTest,AluminumContentPPM,ProductType
• Example (sterility: 0=sterile, 1=contaminated):
• ⚠️ CRITICAL:
• • Radiochemical purity ≥95% — Low RCP reduces contrast. For cardiology, absence of colloid is particularly important because the liver is located directly beneath the heart. Liver background can mimic or mask uptake in the heart.
• • Aluminum Breakthrough ≤10 ppm — CRITICAL PARAMETER. Aluminum ions react with pyrophosphate, forming insoluble particles. This leads to uptake by RES cells of liver and spleen ("hot liver"), which completely distorts the image of the heart and lower ribs.
• • Free pertechnetate ≤5% — Artifacts in thyroid and stomach area.
• • Reduced/Hydrolyzed Tc ≤5% — Colloid accumulating in liver.

URS — User Requirements Specification

input.csv contract

BatchNumber,TotalActivityMBq,RadiochemicalPurityPercent,FreePertechnetatePercent,ReducedHydrolyzedTcPercent,pH,EndotoxinsEU,SterilityTest,AluminumContentPPM,ProductType
TC99M-PYP-2026-090,740.0,97.0,2.0,1.0,6.0,10.0,0,1.5,CardiacAmyloidosis
TC99M-PYP-BONE-091,800.0,96.5,2.5,1.0,6.2,12.0,0,2.0,BoneImaging
TC99M-PYP-AL-FAIL,700.0,95.0,3.0,2.0,6.5,15.0,0,12.0,CardiacAmyloidosis

FS — Functional Specification

Example output.json

{
  "utilityId": "technetium99m-pyrophosphate-checker",
  "api": "Tc-99m PYP",
  "overallStatus": "PASS|WARNING|FAIL",
  "sourceFile": "input.csv",
  "checks": [
    {
      "parameter": "BatchNumber",
      "value": "TC99M-PYP-2026-090",
      "status": "PASS|WARNING|FAIL",
      "message": "Rule-based check result"
    },
    {
      "parameter": "TotalActivityMBq",
      "value": "740.0",
      "status": "PASS|WARNING|FAIL",
      "message": "Rule-based check result"
    },
    {
      "parameter": "RadiochemicalPurityPercent",
      "value": "97.0",
      "status": "PASS|WARNING|FAIL",
      "message": "Rule-based check result"
    },
    {
      "parameter": "FreePertechnetatePercent",
      "value": "2.0",
      "status": "PASS|WARNING|FAIL",
      "message": "Rule-based check result"
    },
    {
      "parameter": "ReducedHydrolyzedTcPercent",
      "value": "1.0",
      "status": "PASS|WARNING|FAIL",
      "message": "Rule-based check result"
    },
    {
      "parameter": "pH",
      "value": "6.0",
      "status": "PASS|WARNING|FAIL",
      "message": "Rule-based check result"
    },
    {
      "parameter": "EndotoxinsEU",
      "value": "10.0",
      "status": "PASS|WARNING|FAIL",
      "message": "Rule-based check result"
    },
    {
      "parameter": "SterilityTest",
      "value": "0",
      "status": "PASS|WARNING|FAIL",
      "message": "Rule-based check result"
    }
  ],
  "criticalFindings": []
}

OQ/PQ test scenarios

QA/QC and change control

• Do not rename columns without updating the validator and test set.
• Retain input.csv, output.json, executable version and checksum.
• Before production use, perform IQ/OQ/PQ or equivalent CSV/CSA verification.
• Critical radiopharmaceutical limits must be verified against the approved specification and local SOPs.