Local and average gloss from flat-faced sodium chloride tablets.

Area of Science:

• Materials Science
• Pharmaceutical Technology

Background:

• Tablet surface properties are critical for drug performance and manufacturing.
• Assessing surface structure changes often requires complex imaging techniques.

Purpose of the Study:

• To detect local gloss and surface structure changes in sodium chloride tablets.
• To evaluate the utility of a diffractive optical element-based glossmeter (DOG) for characterizing tablet surfaces.
• To correlate gloss variations with surface roughness and structural changes.

Main Methods:

• Utilized a diffractive optical element-based glossmeter (DOG) to create 2D gloss maps of tablet surfaces.
• Compared DOG gloss measurements with scanning electron microscopy (SEM) and diamond stylus profilometry.
• Analyzed surface roughness changes in relation to compression force.

Main Results:

• Profilometry indicated decreased surface roughness with increased compression force.
• Average gloss values decreased with increasing compression force, contrary to expectations for smoother surfaces.
• DOG detected gloss loss in individual sodium chloride particles due to fragmentation and cracking, correlating with SEM findings.
• Local gloss variation provided detailed insights into tablet surface structural modifications.

Conclusions:

• Diffractive optical element-based glossmetry is a viable method for detecting local surface structure changes in tablets.
• Gloss variation analysis offers valuable information complementary to traditional surface roughness measurements.
• Understanding gloss changes provides critical data on tablet material behavior under compression.