Colour measurement of liquid biopharmaceutical products with the UltraScan VIS spectrophotometer

In the pharmaceutical industry, the precise determination of the colour of transparent liquid products is crucial in development and quality management. Accurate colour measurement in transmission according to CIE and ASTM standards is essential to qualify the colour of liquid APIs, injectables and other liquid products according to international pharmaceutical guidelines. In particular, the exact assignment of internationally defined colour numbers must be guaranteed even for the smallest sample quantities. HunterLab colour measurement offers the perfect solution to meet these requirements, providing the pharmaceutical industry with reliable, accurate colour values and colour numbers – even with minimal sample quantities.

The task

In addition to the exact measurement of the CIE L*a*b* colour values, the reliable determination of various colour numbers, such as the EP colour number EP 2.2.2, the USP colour number, the Apha colour number or the determination of the Haze value in the analysis of pharmaceutical liquids is also required. When measuring colour in transmission, often only very small quantities of the product are available.

With the UltraScan VIS spectrophotometer, transparent liquid pharmaceutical products can be precisely measured in transmission. In the EasyMatch QC software, all colour numbers commonly used in the pharmaceutical industry can be calculated and displayed immediately in addition to the standard colour scales (see box). If you only want to use very small sample quantities, HunterLab offers various holders and cuvettes that can be used to measure quantities from approx. 300 µl. The layer thickness of 1.0 cm is retained for reliable measurement.

The accessories

The following cuvettes with matching holder:

• Rectangular cells with layer thicknesses from 2 mm to 50 mm
• Macro cuvettes (from 2.5 ml)
• Semi-microcuvettes (from 0.6 ml)
• Ultra-microcuvettes (from 300 µl)