Nitrogen13AmmoniaQualityChecker

URS & FS — User Requirements and Functional Specification

This document describes the controlled interface and behaviour of Nitrogen13AmmoniaQualityChecker for Nitrogen-13 Ammonia.

Domain limits and critical parameters

• ℹ️ Utility checks critical parameters of [13N]Ammonia:
• • Radionuclidic purity (≥99.5%)
• • Fluorine-18 impurity (≤0.1%)
• • Radiochemical purity (≥95%)
• • Nitrate/Nitrite (≤5%)
• • pH (4.5–8.5), endotoxins, sterility
• ⚠️ CRITICAL: F-18 impurity >0.1% distorts quantitative blood flow analysis!
• BatchNumber,TotalActivityMBq,RadionuclidicPurityPercent,Fluorine18ImpurityPercent,RadiochemicalPurityPercent,NitrateNitritePercent,pH,EndotoxinsEU,SterilityTest,HeavyMetalsPPM,ProductType
• Example (sterility: 0=sterile, 1=contaminated):
• ⚠️ CRITICAL:
• • Radiochemical purity ≥95% — Only ammonia ([13N]NH3) is effectively taken up by the myocardium. Oxidized forms ([13N]NOx) do not accumulate and create blood pool background.
• • Fluorine-18 impurity ≤0.1% — F-18 (T½=110 min) is often formed as a byproduct. Due to its long half-life, F-18 creates a constant background, distorting dynamic input-output curves in kinetic modeling.
• • Nitrate/Nitrite ≤5% — Radiolysis and oxidation products. Do not participate in myocardial metabolism.
• • Control of F-18 impurity (critical for quantitative analysis)

URS — User Requirements Specification

input.csv contract

BatchNumber,TotalActivityMBq,RadionuclidicPurityPercent,Fluorine18ImpurityPercent,RadiochemicalPurityPercent,NitrateNitritePercent,pH,EndotoxinsEU,SterilityTest,HeavyMetalsPPM,ProductType
N13-NH3-2026-001,15000.0,99.9,0.01,99.5,0.2,6.5,20.0,0,1,Cardiac_PET
N13-NH3-2026-002,14500.0,99.0,0.5,94.0,6.5,7.0,150.0,0,5,Cardiac_PET
N13-NH3-2026-003,16000.0,99.95,0.005,99.8,0.1,6.8,10.0,0,0.5,Cardiac_PET

FS — Functional Specification

Example output.json

{
  "utilityId": "nitrogen13-ammonia-quality-checker",
  "api": "Nitrogen-13 Ammonia",
  "overallStatus": "PASS|WARNING|FAIL",
  "sourceFile": "input.csv",
  "checks": [
    {
      "parameter": "BatchNumber",
      "value": "N13-NH3-2026-001",
      "status": "PASS|WARNING|FAIL",
      "message": "Rule-based check result"
    },
    {
      "parameter": "TotalActivityMBq",
      "value": "15000.0",
      "status": "PASS|WARNING|FAIL",
      "message": "Rule-based check result"
    },
    {
      "parameter": "RadionuclidicPurityPercent",
      "value": "99.9",
      "status": "PASS|WARNING|FAIL",
      "message": "Rule-based check result"
    },
    {
      "parameter": "Fluorine18ImpurityPercent",
      "value": "0.01",
      "status": "PASS|WARNING|FAIL",
      "message": "Rule-based check result"
    },
    {
      "parameter": "RadiochemicalPurityPercent",
      "value": "99.5",
      "status": "PASS|WARNING|FAIL",
      "message": "Rule-based check result"
    },
    {
      "parameter": "NitrateNitritePercent",
      "value": "0.2",
      "status": "PASS|WARNING|FAIL",
      "message": "Rule-based check result"
    },
    {
      "parameter": "pH",
      "value": "6.5",
      "status": "PASS|WARNING|FAIL",
      "message": "Rule-based check result"
    },
    {
      "parameter": "EndotoxinsEU",
      "value": "20.0",
      "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.