ParticleSizeDistributionChecker
Particle Size Distribution
Particle Size Distribution Checker — Particle Size Analysis (ISO 13485, Ph. Eur.)
ℹ️ The utility checks D10, D50, D90, max size, agglomerates, Span (homogeneity).
ℹ️ Does not use machine learning — rule-based logic only.
⚠️ CRITICAL! D_Max > 800 µm needle clogging risk. Agglomerates > 1% granuloma risk!
Usage:
ParticleSizeDistributionChecker.exe → demo mode
ParticleSizeDistributionChecker.exe input.csv output.json → evaluate data
Input format:
BatchNumber,D10_um,D50_um,D90_um,D_Max_um,Agglomerates_Percent,Span_Value,Concentration_ParticlesPerMl,Viscosity_Pa_s,pH_Value,SterilityTest,Endotoxin_EU_ml,Measurement_Method
Example:
PSD-HA-2026-001,45.0,150.0,350.0,480.0,0.3,2.03,50000,20.0,7.1,0,0.1,LaserDiffraction
— WHY IS THIS NEEDED?
Particle size distribution — critical quality parameter for homogenized fillers (HA, CaHA, PLLA):
• Determines passability through thin needles (27G, 30G)
• Affects injection smoothness and risk of lumps/granulomas
• D50 (median) characterizes average particle size
• D90 and D_Max control presence of large outlier particles
• Span ((D90-D10)/D50) shows distribution homogeneity (lower is better)
⚠️ CRITICAL:
• D_Max ≤ 800 µm — larger particles may clog needle or cause embolism
• Agglomerates ≤ 1% — clumped particles are main cause of granulomas and skin irregularities
• D50 in range 20–400 µm — optimal for most facial areas
• Span ≤ 2.5 — ensures predictable gel behavior
• Sterility and endotoxins — mandatory for all injectable forms
⚠️ Note: Measurement performed by laser diffraction, dynamic light scattering, or automated microscopy. Important to control not only averages but also distribution "tails" (D90, D_Max), as large particles cause injection problems. Agglomerates may form during improper storage or synthesis. Homogeneity (low Span) critical for uniform filler distribution in tissues.
input.csv
BatchNumber,D10_um,D50_um,D90_um,D_Max_um,Agglomerates_Percent,Span_Value,Concentration_ParticlesPerMl,Viscosity_Pa_s,pH_Value,SterilityTest,Endotoxin_EU_ml,Measurement_Method PSD-HA-2026-001,45.0,150.0,350.0,480.0,0.3,2.03,50000,20.0,7.1,0,0.1,LaserDiffraction
URS & FS — user requirements and functional specification
This document defines user requirements and functional specification for the quality-control utility. It supports deployment discussion, IQ/OQ preparation and QC workflow integration.
1. Scope
The Particle Size Distribution Checker utility is used for Particle Size Distribution. The actual input.csv is the source of truth for the input structure; control criteria are defined by the executable and the domain description.
The utility does not use machine learning; decisions are produced by deterministic rules.
Categories: Dermal fillers, EAEU pharmacopoeia
Tags: dermal fillers, dissolution, EAEU, endotoxins, hyaluronic acid, impurities, injectables, microbiology, particles, pharmacopoeia, rheology, specification, sterility
2. Execution modes
ParticleSizeDistributionChecker.exe → demo mode ParticleSizeDistributionChecker.exe input.csv output.json → evaluate data
3. Key controlled areas
- assay / content
- dissolution / disintegration
- microbiology and pathogens
- pH and physicochemical parameters
4. Domain limits and critical parameters
- ⚠️ CRITICAL! D_Max > 800 µm needle clogging risk. Agglomerates > 1% granuloma risk!
- ⚠️ CRITICAL:
- D_Max ≤ 800 µm — larger particles may clog needle or cause embolism
- Agglomerates ≤ 1% — clumped particles are main cause of granulomas and skin irregularities
- D50 in range 20–400 µm — optimal for most facial areas
- Span ≤ 2.5 — ensures predictable gel behavior
- Sterility and endotoxins — mandatory for all injectable forms
- ⚠️ Note: Measurement performed by laser diffraction, dynamic light scattering, or automated microscopy. Important to control not only averages but also distribution "tails" (D90, D_Max), as large particles cause injection problems. Agglomerates may form during improper storage or synthesis. Homogeneity (low Span) critical for uniform filler distribution in tissues.
5. URS — user requirements
| ID | Requirement | Criticality | Acceptance criterion |
|---|---|---|---|
| URS-001 | The system shall accept an input.csv file for Particle Size Distribution with the exact columns listed in the “Input data contract” section. | High | A file with the correct header is processed without manual editing; missing mandatory columns produce FAIL/import error. |
| URS-002 | The system shall support execution without arguments in demo mode and execution with input.csv output.json for user data. | Medium | Both execution scenarios produce a predictable result or clear diagnostic error. |
| URS-003 | The system shall perform rule-based controls for: assay / content, dissolution / disintegration, microbiology and pathogens, pH and physicochemical parameters. | High | Each controlled parameter receives a status and message; the result does not depend on hidden Excel formulas or ML. |
| URS-004 | The system shall preserve traceability between batch/lot, source values, applied rules and final verdict. | High | Output includes batch identifier, source values, parameter statuses and critical findings. |
| URS-005 | The system shall generate machine-readable output.json for LIMS/ELN/MES, batch record and QA/QC review. | High | JSON contains overall status, check array, warnings, failures and source-file reference. |
| URS-006 | The system shall support use in the client validation package: URS/FS, IQ/OQ preparation, installation and operational scenario checks. | High | The document, test scenarios and reproducible CSV/JSON flow are suitable for audit and internal approval. |
| URS-007 | The system shall clearly separate technical data errors from specification nonconformities. | Medium | Schema/type errors are not mixed with pharmacopoeial deviations and are reported separately. |
6. input.csv data contract
The source of truth for the input schema is the actual input.csv header. Column names are technical identifiers and are not translated.
| # | Column | Type | Unit | Description | Sample | Control rule |
|---|---|---|---|---|---|---|
| 1 | BatchNumber | identifier | as specified | Batch Number | PSD-HA-2026-001 | mandatory field; used for batch/lot traceability |
| 2 | D10_um | decimal | µm | D10 um | 45.0 | mandatory numeric value; rule comparison is performed by the utility |
| 3 | D50_um | decimal | µm | D50 um | 150.0 | mandatory numeric value; rule comparison is performed by the utility |
| 4 | D90_um | decimal | µm | D90 um | 350.0 | mandatory numeric value; rule comparison is performed by the utility |
| 5 | D_Max_um | decimal | µm | D Max um | 480.0 | mandatory numeric value; rule comparison is performed by the utility |
| 6 | Agglomerates_Percent | decimal | % | Agglomerates % | 0.3 | mandatory numeric value; rule comparison is performed by the utility |
| 7 | Span_Value | decimal | as specified | Span Value | 2.03 | mandatory numeric value; rule comparison is performed by the utility |
| 8 | Concentration_ParticlesPerMl | decimal | as specified | Concentration Particles per Ml | 50000 | numeric value; compared with assay/purity limit from specification or method |
| 9 | Viscosity_Pa_s | decimal | as specified | Viscosity Pa s | 20.0 | mandatory numeric value; rule comparison is performed by the utility |
| 10 | pH_Value | decimal | pH | p H Value | 7.1 | mandatory numeric value; rule comparison is performed by the utility |
| 11 | SterilityTest | boolean / flag | 0/1 | Sterility Test | 0 | valid flag required; prohibited organisms and growth are normally expected as 0 / absent |
| 12 | Endotoxin_EU_ml | decimal | as specified | Endotoxin EU ml | 0.1 | numeric value; critical safety attribute compared with endotoxin limit |
| 13 | Measurement_Method | text | as specified | Measurement Method | LaserDiffraction | mandatory value; format and acceptability are checked by the utility |
CSV example
BatchNumber,D10_um,D50_um,D90_um,D_Max_um,Agglomerates_Percent,Span_Value,Concentration_ParticlesPerMl,Viscosity_Pa_s,pH_Value,SterilityTest,Endotoxin_EU_ml,Measurement_Method PSD-HA-2026-001,45.0,150.0,350.0,480.0,0.3,2.03,50000,20.0,7.1,0,0.1,LaserDiffraction
7. FS — functional specification
| ID | Function | Implementation description |
|---|---|---|
| FS-001 | CLI entry point | The executable ParticleSizeDistributionChecker.exe supports demo mode and input.csv output.json processing mode. |
| FS-002 | CSV parser | The import module reads CSV, validates header, column presence/order, value count and encoding. Decimal values are expected with a dot separator. |
| FS-003 | Field conversion | Each column is converted to the expected type: identifier, text, decimal number, date/time or boolean flag. |
| FS-004 | Domain rule engine | For Particle Size Distribution, explicit rules are applied: range, minimum, maximum, absence of prohibited flag, data completeness or calculation-based check. |
| FS-005 | Criticality handling | Critical violations produce FAIL; non-critical deviations and incomplete data produce WARNING; full conformance produces PASS. |
| FS-006 | JSON writer | output.json stores overall status, per-parameter results, source values, warnings, failures and diagnostic messages. |
| FS-007 | Integration contract | The CSV → JSON format is stable for invocation from LIMS/ELN/MES, scheduled task or wrapper service. |
| FS-008 | Error handling | Schema error, missing file, non-numeric value or JSON write failure returns diagnosable error without silent PASS. |
8. output.json contract
The output file must be suitable for automated processing, audit review and correlation with the source input.csv row.
{
"utility": "ParticleSizeDistributionChecker",
"api": "Particle Size Distribution",
"batchNumber": "PSD-HA-2026-001",
"overallStatus": "PASS|WARNING|FAIL",
"checkedAtUtc": "2026-05-18T00:00:00Z",
"checks": [
{
"parameter": "BatchNumber",
"value": "PSD-HA-2026-001",
"unit": "as specified",
"status": "PASS|WARNING|FAIL",
"message": "Rule-based check result"
},
{
"parameter": "D10_um",
"value": "45.0",
"unit": "µm",
"status": "PASS|WARNING|FAIL",
"message": "Rule-based check result"
},
{
"parameter": "D50_um",
"value": "150.0",
"unit": "µm",
"status": "PASS|WARNING|FAIL",
"message": "Rule-based check result"
},
{
"parameter": "D90_um",
"value": "350.0",
"unit": "µm",
"status": "PASS|WARNING|FAIL",
"message": "Rule-based check result"
},
{
"parameter": "D_Max_um",
"value": "480.0",
"unit": "µm",
"status": "PASS|WARNING|FAIL",
"message": "Rule-based check result"
},
{
"parameter": "Agglomerates_Percent",
"value": "0.3",
"unit": "%",
"status": "PASS|WARNING|FAIL",
"message": "Rule-based check result"
},
{
"parameter": "Span_Value",
"value": "2.03",
"unit": "as specified",
"status": "PASS|WARNING|FAIL",
"message": "Rule-based check result"
},
{
"parameter": "Concentration_ParticlesPerMl",
"value": "50000",
"unit": "as specified",
"status": "PASS|WARNING|FAIL",
"message": "Rule-based check result"
}
],
"criticalFindings": [],
"sourceFile": "input.csv"
}9. OQ/PQ test scenarios
| ID | Scenario | Expected result |
|---|---|---|
| TC-001 | Valid CSV with expected header and sample row | All rows are processed; output contains PASS/WARNING/FAIL and parameter-level detail. |
| TC-002 | A mandatory input.csv column is missing | Import is rejected or the row receives FAIL with schema reference. |
| TC-003 | A numeric field contains text or a blank value | Type conversion error is recorded; the result is not hidden as PASS. |
| TC-004 | A parameter is outside specification or critical limit | Critical parameters produce FAIL; non-critical deviations produce WARNING according to the rule. |
| TC-005 | Positive pathogen/microbiological flag or microbiological limit excursion | Critical FAIL is produced with the offending parameter. |
10. QA/QC, CSV and change control
- Before production use, the client records executable version, checksum, specification/monograph version, test CSV, expected JSON and IQ/OQ results.
- Column names must not be changed without updating the validator and test scenarios.
- The source CSV, output.json and utility version should be stored together as an evidence package.
- Any change in control rules must go through change control and repeated OQ scenario verification.
Included in packages
Dental & Dental Materials QC Suite
QC utility package for dental medicinal products, oral-care products and dental materials: anaesthetics, antiseptics, analgesic/anti-infective products, polymers/minerals, resins, bonding workflows, microbiology, stability and material QC.
OpenDermal Fillers QC Suite
Package for injectable implants and dermal fillers: hyaluronic acid, CaHA, PLLA, PMMA, collagen and related tests.
OpenEAEU Pharmacopoeia QC Suite
Package for EAEU pharmacopoeial methods: specifications, dissolution, microbiology, impurities and general tests.
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