UVVisIdentityAssayQualityChecker

UV-Vis Identity & Assay Quality Checker — Control of Identity and Content (UV Spectroscopy)

ℹ️ Utility checks identity and quantitative content of active pharmaceutical ingredients by UV spectroscopy according to Pharmacopoeia requirements:
• Position of absorption maximum (Lambda Max) — main identity criterion
• Specific Absorbance A(1%, 1 cm) — characteristic of purity and identity
• Absorbance ratio at different wavelengths — additional identity criterion
• Quantitative content (Assay %) — calculation based on Beer-Lambert law

⚠️ CRITICAL: Shift in lambda max (>±1 nm) may indicate impurities, degradation, or wrong solvent!
Specific absorbance value must strictly fall within narrow limits specified in the monograph.

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

Input format:
BatchNumber,ProductName,LambdaMax_nm,AbsorbanceAtLambdaMax,SpecificAbsorbance_A1cm1,AssayPercent,AbsorbanceRatio_250_300,PathLength_cm,Concentration_g_per_100ml

Example:
UV-2026-API-001,Paracetamol,243.0,0.850,850.0,99.8,1.85,1.0,0.001

— WHY IS THIS NEEDED?
UV spectroscopy is a fast and reliable method for identifying substances with chromophore groups.
It is widely used for incoming raw material control and finished product control.
Combination of peak position and absorbance magnitude provides high confidence in identification.

⚠️ CRITICAL:
• Lambda Max: Must match reference standard. Solvent strongly affects peak position (solvatochromism).
• Specific Absorbance A(1%, 1 cm): Calculated as A / (c * l), where c is concentration in g/100 ml, l is path length in cm.
• Beer-Lambert Law: Valid only for dilute solutions. Deviations occur at high concentrations.
• Cuvette Cleanliness: Scratches or dirt on cuvette distort absorbance results.

Key features:
• Check of spectral identity parameters
• Calculation and control of specific absorbance
• Assessment of quantitative content (Assay)
• Generation of reports for QC and LIMS LabWare
• Compliance with general Pharmacopoeia chapters on spectroscopy

Critical parameters:
• Lambda Max: within ±1-2 nm of standard
• Specific Absorbance: within limits specified in monograph (e.g., ±2-3%)
• Assay: 98.0–102.0% (for APIs)
• Absorbance Ratio: within established limits

💡 Usage tips:
1. Solvent: Use only the solvent specified in the method (often alcohol, water, or buffer).
2. Scanning: Before measuring absorbance, it is recommended to scan full spectrum (e.g., 200-400 nm) to check peak shape.
3. Blank: Always subtract spectrum of pure solvent (Blank).
4. Absorbance Range: Most accurate measurements are in absorbance range 0.2–0.8. Avoid values >1.5.
5. Calibration: Check wavelength and photometric accuracy of instrument using filters (e.g., holmium oxide).

⚠️ Note: UV method is not specific for complex mixtures, as many substances absorb in similar regions. For complex matrices, HPLC is preferred. However, for individual APIs, it is an excellent tool.