Metrohm NIRS XDS SmartProbe Analyzer - Manual (Page 36)

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Reference Standardization is not technically
required for the Interactance Immersion tip,
because air is used as a reference, and it is
assumed to be 100% transmissive.
However, Reference Standardization is required for
Instrument Calibration, and should be selected in
Configure, Options.
Instrument Calibration must be performed in the
Reflectance mode. After mounting the
Interactance Immersion tip, run Wavelength
Linearization if Auto-Linearization is selected under
Project Options.
Always follow these guidelines when handling sample materials:
1. Always use appropriate safety equipment with hazardous materials, to prevent injury. This
equipment may include safety glasses, gloves, lab apron, and fume hood. Always check the
MSDS (Material Safety Data Sheet) for the materials being analyzed for recommended
handling precautions.
2. When inserting the reflectance tip into powdered samples, try to press it consistently each
time. This provides fairly uniform “sample packing” in front of the sample window, and gives
minimal baseline differences in spectra.
3. Be sure the probe end is not at the extreme edge of the container, where sample material
may be thin. The probe should always see “infinite thickness” of powder for best operation.
This varies with material, but 13mm or 1/2” is generally considered sufficient.
Cleaning the Probe End:
Following analysis, the probe end should be cleaned to prevent sample carryover, which could affect
analysis. Cleaning depends upon the sample material. Always follow the precautions on the MSDS
when performing cleaning. Normal samples and cleaning methods include:
Sample Type Cleaning Method
Free-flowing crystalline materials, pellets,
fibrous samples
Wipe from probe end with disposable lab wipe.
Wipe probe window with dampened wipe. Rinse
with de-ionized water, and dry thoroughly.
Dense powders which tend to clump, thick
slurries
Wipe from probe sampling area with spatula or
wooden tongue depressor. Clean window using a
mild detergent solution, rinse, then dry.
Thick, pasty samples with high oil content
Dig out using spatula or wooden tongue
depressor. Wash cell and window in a strong
detergent to remove all residual sample material.
Rinse and dry.
Pharmaceutical applications may require a “Cleaning validation” which describes each step of the
cleaning process, solvents to be used, and specific verification tests to determine whether cleanliness