BUCHI NIRFlex N-500 - Manual (Page 61)

6 Operation
61 NIRFlex N-500 Operation Manual, Version F
Typical samples for the NIRFlex Solids Transmittance include tablets, hard gelatin capsules, powders
or soft gelatin capsules including semi-liquids or oily liquids, which requires a very high dynamic photo-
metric range of the system. The design of the measuring cell takes this requirement into account.
Without any special settings the user will generate spectra with optimized signal-to-noise ratio for his
specific samples.
For reproducible and accurate results in tablet transmission measurements, it is essential to prevent
stray light caused by light passing around the side of the tablets. Therefore the sample plates are
individually customized in order to fit perfectly for your tablets and to ensure the optimal performance.
Additionally the sample plates exhibit a specially selected coating to prevent reflection and light
leakage.
All sample plates include an External Reference position. By default reference measurements are
performed automatically before every measurement sequence.
NOTICE
Risk of damage at the coating of the sample plate
Do not cleat the sample plate in a dishwasher •
Clean the sample plate with Ethanol and a soft, lint-free tissue •
6 .6 NIRFlex Liquids
System preparation
The liquid cell must reach a stable working temperature before a measurement can be performed. The
heat-up time depends on the ambient temperature.
Starting at standard ambient temperature of 25 °C the measurement cell needs:
approximately 15 minutes to stabilize at 35 °C. •
approximately 30 minutes to stabilize at 60 – 65 °C. •
NOTICE
Risk of measurement errors by unsufficient heat-up time
Cuvettes and sample material must be completely heated-up at measurement •
Depending on the heat distribution and the positioning of the cuvettes the temperature difference
between probe and liquid temperature is about 2 °C at a measurement temperature of 65 °C.
NIRFlex Liquids measurement cell