Negative Mode Detection of Pigments in Cosmetics using the MALDI-8030 Dual Polarity Benchtop MALDI-TOF Mass Spectrometer

Significance of the Topic

Color and pigment identity in cosmetic products play a critical role in consumer safety, regulatory compliance and lifestyle choices. With the global cosmetics market exceeding USD 863 billion in 2024, rapid and reliable analytical methods are needed to verify ingredient lists, ensure adherence to vegan, halal or organic standards, and detect potential allergens such as carmine.

Objectives and Study Overview

This study demonstrates a straightforward workflow for extracting and detecting color pigments from commercial lipsticks using the MALDI-8030 dual polarity benchtop linear TOF mass spectrometer. Four market segments were represented: non-vegan/non-organic (two shades), organic/non-vegan, and vegan/halal. The goal was to confirm labeled pigments and assess method suitability for routine quality control in cosmetic analysis.

Methodology and Instrumentation

Sample Preparation:

• Approximately 10 mg of lipstick dissolved in 50 µL water/methanol (1:1)
• Sonication for 30 min to extract pigments into solution
• Centrifugation to remove solids and recover pigment-containing supernatant

Matrix and Analysis:

• Matrix: 9-Aminoacridine (10 mg/mL in methanol)
• Analysis: MALDI-8030 in negative ion mode for pigment mass profiling
• Confirmation: MALDI-7090 MS/MS for select standards and samples (not required for routine screening)

Used Instrumentation

• MALDI-8030 dual polarity benchtop linear MALDI-TOF mass spectrometer (negative ion mode)
• MALDI-7090 for MS/MS confirmation
• Sonicator and benchtop centrifuge for sample preparation

Main Results and Discussion

Non-vegan/Non-organic Lipstick 1:

• Detected CI 15850 (Red 7), CI 15985 (Yellow 6 Lake) and CI 45380 (Red 22 Lake)
• No signal for CI 45410 (Red 28), CI 19140 (Yellow 5), CI 42090 (Blue 1 Lake) or CI 75470 (Carmine)

Non-vegan/Non-organic Lipstick 2:

• Detected CI 15850 (Red 7), CI 15985 (Yellow 6 Lake) and CI 19140 (Yellow 5 Lake)
• No signal for CI 45380, CI 42090 or CI 75470

Organic (Non-vegan) Lipstick 3:

• Only CI 75470 (Carmine) detected, consistent with label but flagged as allergenic and non-halal

Vegan/Halal (Non-organic) Lipstick 4:

• Detected CI 12085 and CI 15850:1, matching ingredient list
• No carmine signal, confirming compliance with vegan/halal requirements

Isotopic patterns and exact mass measurements provided high confidence in pigment identification, while MS/MS confirmation supported assignments for non-characteristic species.

Benefits and Practical Applications

The proposed method enables rapid, low-cost screening of cosmetic pigments with minimal sample preparation. Quality spectra in negative ion mode deliver accurate mass and isotopic information, facilitating:

• Verification of regulatory labeling (EU 1223/2009)
• Screening for allergens and non-permissible pigments in vegan/halal products
• Quality control in R&D and production environments

Future Trends and Applications

Potential developments include quantitative MALDI workflows for pigment concentration assessment, expansion to other beauty products (eyeshadows, foundations), integration with automated sample handling, and the use of portable MALDI-TOF systems for in-field testing. Advances in matrix selection and data analysis algorithms may further improve sensitivity and specificity for complex formulations.

Conclusion

The MALDI-8030 benchtop linear TOF offers a simple, efficient approach to qualitative pigment profiling in lipsticks across diverse market segments. The method meets industry requirements for speed, accuracy and compliance, and can be readily adopted for routine cosmetic safety and authenticity testing.

Reference

1. Zion Market Research (2018). A Global Cosmetic Products Market Size, Share 2017: Industry Trends, Growth Analysis and Forecast, 2024.
2. Riaz MN, Chaudry MM (2018). Halal Food Model. In Handbook of Halal Food Production, p. 30.