THE LAB

Mérieux NutriSciences | Pharma & HealthCare quality control laboratories are an essential pillar to ensure the safety, efficacy and quality of MSDs and biocide products. With a wide range of analytical techniques, compliance with all regulatory standards is ensured. Our qualified scientists use advanced tools and technologies to provide highly accurate and reliable results.

• Wide analytical offer: over 13,000 procedures developed according to official standards and customized methods.
• Variety of analytical techniques: more than 50 techniques available for complete analysis.
• Excellence in quality systems: compliance with rigorous GLP and GMP standards to ensure maximum accuracy and reliability.

PHYSICAL-CHEMICAL ANALYSIS

Physical-chemical analyses are essential to evaluate the properties and safety of MSDs and biocides, in order to characterize products, verify batch quality and ensure regulatory compliance.

• Analysis of chemical parameters (acidity/basicity, solubility, density).
• Physical properties (viscosity, surface tension, melting point).
• Chemical compatibility and formulation stability.
• Validation of the analytical method according to international guidelines.The analyses are performed in compliance with CIPAC, OECD and CLP regulations, with
• GLP and ISO 17025 certifications.

Physical-chemical analyses require advanced instruments and specialized skills. The main challenges include:

• The complexity of formulations, which can affect stability and efficacy.
• The need to adapt testing to new regulations and emerging requirements.
• The integration of innovative methods, such as high-resolution mass spectrometry
• (HRMS), for the identification of impurities and contaminants.

The analyses of physical-chemical properties include a wide range of tests, and are performed at our laboratories or qualified partners’:

1. Physical-chemical properties:

• Spectral data (UV/Vis, IR, NMR, MS/HRMS, XRD, SEM-EDX)
• Appearance and infiltration data
• Acidity/Alkalinity
• Relative and apparent density
• Physical and chemical compatibility with other products
• Surface tension
• Viscosity
• Melting point, freezing point, boiling point
• Solubility in water and organic solvents
• Distribution coefficient
• Dissociation constant

2. Physical risks:

• Flash point
• Flammability of solids
• Corrosiveness on metals

3. Technical properties:

• Wettability
• Suspensibility, spontaneity and stability of dispersion
• Dry and wet sieve analysis
• Emulsifying capacity, re-emulsifying capacity and emulsion stability
• Time of disintegration
• Granulometric distribution, friability
• Burn rate and completeness
• Degree of dissolution and stability to dilution
• Technical properties of aerosols

4. Active ingredient titles. The content of the active substance may vary from batch to batch, so it is essential to define specifications (tolerance) compared to the nominal value at the time of production.

Table 5. Tolerance limits of the active substance content at the point of manufacture
DECLARED NOMINAL CONTENT OF ACTIVE [g/kg or g/l]	TOLERANCE LIMIT
Up to 25	±15% of the declared nominal content for homogeneous formulations (e.g. emulsifiable concentrates, soluble concentrates, concentrates in aqueous suspension) ±25% of the declared nominal content for homogeneous preparations (e.g. granules, water-dispersible granules)
Above 25 up to 100	±10% of the declared nominal content
Above 100 up to 250	±6% of the declared nominal content
Above 250 up to 500	±5% of the declared nominal content
Above 500	±25 g/kg or g/l of the declared nominal content

5. Analysis of physical-chemical parameters and technical properties

Define such parameters and properties to be controlled

• based on the physical nature of the product (solid, liquid)
• for its use (ready-to-use product, concentrated product to be diluted)
• to its packaging/delivery system.

Additionally, depending on the nature of the product and the active substance, it may be required that hazard checks are carried out in accordance with the CLP Regulation.

Parameters to evaluate for a product in trigger related to the formulation type

• 3.5.6 Droplet size (aerosols & sprays) + MMAD Mass Median Aerodynamic Diameter
• 3.5.12 Evaluation of aerosol spray patterns
• 3.5.13 Trigger sprayer operability: nozzle blockage/spray diameter/average amount of spray delivered

Parameters to evaluate for a concentrated liquid product

• 3.5.7 Persistent foaming
• 3.7 Dilution stability

A fundamental aspect is the validation of the analytical methods used to demonstrate their suitability for the intended purpose, evaluating:

• Linearity and application range
• Specificity towards the active substance or impurities
• Repeatability and reproducibility
• Accuracy (percentage of recovery of the active substance)

Importance of analyses for regulatory compliance. Regulatory authorities require detailed characterization of biocides, both during the registration process and for post- market verification. Physical-chemical analyses not only ensure compliance with legal requirements, but are also essential for

• Ensuring safety of use for operators and end consumers.
• Preventing environmental risks related to distribution and improper use.
• Providing a scientific basis for efficacy and safety claims.

Physical-chemical analyses are an indispensable tool to ensure quality, safety and regulatory compliance, helping to protect public health and the environment.