Quantification of active ingredients in shampoo using near-infrared spectroscopy (NIR)

Significance of the Topic

Shampoo products combine cleaning detergents and functional additives such as preservatives and anti-dandruff agents.
Accurate and rapid analysis of these ingredients is critical for quality control and batch release.
Traditional methods like HPLC require lengthy sample preparation, solvents and generate waste.
Near-infrared spectroscopy (NIRS) offers a fast, non-destructive, solvent-free alternative for simultaneous multi-constituent analysis.

Objectives and Study Overview

This feasibility study aimed to evaluate NIRS for quantifying one preservative and two active ingredients in liquid shampoo.
A total of 48 samples with varying concentrations of components A, B and C were prepared.
The goal was to develop calibration models for each analyte and assess prediction errors.

Methodology and Used Instrumentation

• Instrumentation
  • Metrohm NIRS XDS RapidLiquid Analyzer
  • NIRS Quartz Cuvette Open Top 0.5 mm with spacer
  • Vision Air 2.0 Complete software for data processing
• Data Acquisition
  • Spectra collected in relevant NIR regions for each analyte
  • Second derivative spectral pretreatment
  • Partial Least Squares regression for calibration

Main Results and Discussion

• Preservative A
  • PLS model with 4 factors
  • Standard Error of Calibration (SEC): 0.111% across 0–4% range
• Active Ingredient B
  • PLS model with 4 factors
  • SEC: 0.147% over 0–4% concentration range
• Active Ingredient C
  • PLS model with 2 factors
  • SEC: 0.026% across 0–1% range

The low SEC values and strong correlation plots demonstrate reliable quantification capability of NIRS for multiple analytes in shampoo with analysis times under one minute.

Benefits and Practical Applications

• Non-destructive, solvent-free analysis reduces chemical usage and waste.
• Rapid measurement under one minute supports high-throughput quality control.
• Simultaneous multi-component detection enhances efficiency.
• Eliminates the need for costly chromatography columns and lengthy separations.

Future Trends and Potential Applications

• Extension to other personal care and cosmetic formulations.
• Integration with process analytical technology for real-time monitoring.
• Development of portable NIR systems for on-site quality checks.
• Advanced chemometric methods to further improve prediction accuracy.

Conclusion

Near-infrared spectroscopy has been validated as a rapid and accurate tool for quantification of preservatives and active agents in shampoo.
This approach offers a cost-effective, eco-friendly alternative to conventional chromatographic methods for routine quality control.

Reference

No external literature references were provided in the original text.