Purpose

Define user requirements for a standalone FUZKK utility that accepts laboratory CSV data, evaluates the records using limits embedded in code, and produces LabWare-compatible JSON.

Scope

The utility is intended for preliminary QC/QA review, integration testing, LIMS/LabWare flow and evidence-trail preparation. Final release decisions remain under the laboratory's validated procedure and responsible personnel.

Users

QC analyst, QA reviewer, CSV/validation engineer, LIMS/LabWare integration engineer, responsible laboratory specialist.

User requirements

1. The utility shall run without arguments and print its self-description, a built-in input.csv example from GetDemoData(), and demo evaluation for the embedded records.
2. The utility shall run with two arguments: input.csv output.json.
3. The utility shall not read input.csv and shall not write output.json when started without arguments.
4. CSV numeric values shall be parsed using CultureInfo.InvariantCulture.
5. Output shall be generated as LabWare-compatible JSON with Header, Samples, Results, Status, StatusCode, ErrorMessage, Description and DescriptionEN.
6. For PASS records, ErrorMessage shall be an empty string.
7. Embedded limits shall follow this priority: Ph. Eur. → British Pharmacopoeia / UK implementation → EAEU / regional requirements → EMA/ICH/EU guidance → USP fallback.
8. If an exact monograph is not known, strict standard API limits are used where applicable: assay 98–102%, total impurities ≤1.0%, individual impurity ≤0.5%.
9. For biologics and mAb-like products, aggregation, sterility and endotoxin checks shall be included where relevant to the utility purpose.
10. If a parameter may arrive in different units, the unit shall be represented as a separate input field or explicitly reflected in the input.csv field name.

Input CSV

BatchNumber,ProductName,Monomer_Percent,HMW_Aggregates_Percent,LMW_Fragments_Percent,Mw_Monomer_kDa,Rg_Monomer_nm,Turbidity_NTU,VisualInspection_Score,StressCondition
PEP-AGG-2026-001,Semaglutide API,99.2,0.3,0.5,4.1,1.2,1.5,1.0,None
PEP-AGG-2026-002,Liraglutide Bulk,98.5,0.8,0.7,3.7,1.1,2.0,1.0,Thermal
PEP-AGG-2026-003,Tirzepatide API,97.0,2.5,0.5,4.8,1.4,8.5,3.0,Freeze-Thaw

input.csv fields

Utility description

Peptide Aggregation SEC-MALS Checker — Peptide Aggregation Control (SEC-MALS)

Peptide Aggregation SEC-MALS Checker — Peptide Aggregation Control (SEC-MALS)

ℹ️ Utility analyzes SEC-MALS data for peptides:
• Monomer purity (≥98.0%)
• HMW Aggregates (≤1.0%)
• LMW Fragments (≤1.0%)
• Molecular weight (MALS)
• Turbidity and visual clarity

⚠️ CRITICAL: Peptide aggregates cause immune response!
GLP-1 analogs are prone to fibril formation under stress.

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

Input format:
BatchNumber,ProductName,Monomer_Percent,HMW_Aggregates_Percent,LMW_Fragments_Percent,Mw_Monomer_kDa,Rg_Monomer_nm,Turbidity_NTU,VisualInspection_Score,StressCondition

Example:
PEP-AGG-2026-001,Semaglutide API,99.2,0.3,0.5,4.1,1.2,1.5,1.0,None

— WHY IS THIS NEEDED?
Aggregation control is critical for peptide drugs (Novo Nordisk, Eli Lilly, Gan & Lee):
• Peptides tend to self-associate and form fibrils (amyloids)
• Aggregates can cause unwanted immune response (ADA) in patients
• SEC-MALS allows precise determination of molecular weight and aggregate size without standard calibration
• Important for assessing stability during storage and transport (thermal shock, freezing)

⚠️ CRITICAL:
• Monomer ≥98.0% — ensures dosing accuracy
• HMW Aggregates ≤1.0% — strict safety limit
• LMW Fragments ≤1.0% — chemical degradation control
• Turbidity ≤5.0 NTU — early indicator of precipitation
• Visual clarity — mandatory requirement for injectables

Key features:
• Combined SEC (separation) and MALS (mass detection) analysis
• Immunogenicity risk assessment via aggregate levels
• Stability monitoring under stress tests
• Support for various peptides (Semaglutide, Liraglutide, Tirzepatide)

Critical parameters:
• Monomer: ≥98.0%
• HMW Aggregates: ≤1.0%
• LMW Fragments: ≤1.0%
• Turbidity: ≤5.0 NTU
• Visual Score: 1 (Clear)

💡 Usage tips:
1. Use small pore volume columns for better peptide separation
2. MALS detector distinguishes dimers from larger aggregates
3. Compare profiles before and after stress tests (freeze/thaw, agitation)
4. High turbidity with low SEC aggregates may indicate large insoluble particles
5. For GLP-1 analogs, fibril formation control during long-term storage is especially important

⚠️ Note: Unlike proteins, peptides can form specific structures (fibrils) that are difficult to detect with standard UV detectors. MALS provides absolute mass data, which is critical for confirming the nature of aggregation peaks.

Traceability and limitations

• The URS is used as the source document for functional specification, CSV review and later validation work.
• This document does not replace an approved pharmacopoeial monograph, validated analytical method or internal product specification.
• For product-specific limits, the approved customer specification takes priority.

The functional specification describes the behaviour of the standalone FUZKK console utility, input-data format, evaluation algorithm and output JSON structure.

Functional flow

1. Main() checks the number of arguments.
2. If no arguments are provided: PrintHello() prints the description and built-in input.csv example, then RunDemoEvaluation() executes Evaluate() over GetDemoData() and prints demo JSON.
3. If two arguments are provided: RunWithFiles(input.csv, output.json) reads CSV, evaluates each record and writes LabWare-compatible JSON.
4. LoadData() uses CultureInfo.InvariantCulture and shall not be called in no-arguments mode.
5. Evaluate() returns a named tuple with BatchNumber, ProductName, Parameters, CriticalFailCount, WarningCount, Recommendation and RecommendationEN.
6. GetIssues() builds messages for ErrorMessage in WARNING/FAIL cases.

Evaluation rules

• PASS: CriticalFailCount = 0 and WarningCount = 0.
• WARNING: CriticalFailCount = 0 and WarningCount > 0.
• FAIL: CriticalFailCount > 0.
• ERROR: exception during reading or processing.
• ErrorMessage remains empty for PASS.
• Limits are embedded in Program.cs; no external limit configuration is required.

Input and fields

BatchNumber,ProductName,Monomer_Percent,HMW_Aggregates_Percent,LMW_Fragments_Percent,Mw_Monomer_kDa,Rg_Monomer_nm,Turbidity_NTU,VisualInspection_Score,StressCondition
PEP-AGG-2026-001,Semaglutide API,99.2,0.3,0.5,4.1,1.2,1.5,1.0,None
PEP-AGG-2026-002,Liraglutide Bulk,98.5,0.8,0.7,3.7,1.1,2.0,1.0,Thermal
PEP-AGG-2026-003,Tirzepatide API,97.0,2.5,0.5,4.8,1.4,8.5,3.0,Freeze-Thaw

Output JSON

{
  "Header": {
    "UtilityName": "Peptide_Aggregation_SECMALS_Checker",
    "Version": "1.0.0",
    "Timestamp": "UTC",
    "InstrumentID": "FUZKK-QC-WORKSTATION",
    "OperatorID": "Admin"
  },
  "Samples": [
    {
      "SampleID": "from BatchNumber",
      "BatchNumber": "from CSV",
      "ProductName": "from CSV",
      "TestName": "utility-specific test",
      "AnalysisCode": "utility-specific code",
      "Status": "PASS | WARNING | FAIL | ERROR",
      "StatusCode": "1 | 2 | 0 | -1",
      "ErrorMessage": "",
      "Description": "Russian recommendation",
      "DescriptionEN": "English recommendation",
      "Results": [
        {
          "ParameterName": "parameter",
          "ResultValue": 0.0,
          "UnitOfMeasure": "unit",
          "SpecificationLimit": "limit",
          "IsWithinSpec": true
        }
      ]
    }
  ]
}