Local and average gloss from flat-faced sodium chloride tablets

Abstract

The purpose of this study was to detect local gloss and surface structure changes of sodium chloride tablets. The changes in surface structure were reflected by gloss variation, which was measured using a diffractive optical element-based glossmeter (DOG). By scanning a surface area, we constructed a 2-dimensional gloss map that characterized the tablet's surface structure. The gloss variation results were compared with scanning electron microscopy (SEM) images and average surface roughness values that were measured by conventional diamond stylus profilometry. The profilometry data showed a decrease in tablet surface roughness as a function of compression force. In general, a smoother surface contributes to higher average gloss values. The average gloss values for this material, in contrast, showed a decrease as a function of the compression force. The sequence of particle fragmentation and deformation together with crack formation in sodium chloride particles resulted in a loss of gloss for single sodium chloride particles at the tablet surfaces, which could be detected by the DOG. These results were supported by the SEM images. The results show that detailed information regarding tablets' surface structure changes can be obtained by detection of local gloss variation and average gloss.

Terahertz study on porosity and mass fraction of active pharmaceutical ingredient of pharmaceutical tablets

“…Even though much effort has been devoted to improving the efficacy and safety of pharmaceutical tablets, yet pharmacists are interested in search of fast and nondestructive methods and techniques to optimize the quality and efficacy of all pharmaceutical tablets before reaching the end-users. To achieve this demand, and bearing in mind the number of tablets produced per hour in pharmaceutical industries, pharmacists have recently resorted to the use of optical techniques [1][2][3][4]. This is due to the fact that optical methods can meet the desired measuring speed, for example in THz sensing [5], i.e.…”

Optical and terahertz measurement techniques for flat-faced pharmaceutical tablets: a case study of gloss, surface roughness and bulk properties of starch acetate tablets

“…To avoid this problem, we have recently introduced a novel diffractive glossmeter [12] for the measurement of local and average gloss from sodium chloride tablets. Due to the high resolution of this device, gloss can be detected even from a single particle, and also a very small gloss variation that is beyond the capability of conventional glossmeters [2].…”

“…Conventional glossmeters are sensitive only against the amplitude (intensity) of the reflected light. Since the invention of [12], we have also introduced novel statistical gloss parameters [13], which will be utilized for the first time in the case of pharmaceutical tablets in this paper, which is a novelty of this study. These new parameters are in analogy to the standardized surface roughness parameters.…”

Gloss measurement in detection of surface quality of pharmaceutical tablets: a case study of screening of genuine and counterfeit antimalaria tablets

“…We have developed diffractive optical-element based sensors for surface porosity inspection of two-phase pharmaceutical compacts with flat-faces [7], film coating inspection of oval shaped pharmaceutical tablets [8], single crystal inspection of a pharmaceutical compact [9], and also the detection of surface gloss (surface porosity) of a whole pharmaceutical compact with the aid of gloss map [10].…”