Aspirin/Magnesium Carbonate/Dihydroxyaluminum Aminoacetate

This is the first report of a simultaneous ultraviolet/visible/NIR and longwave infrared laser-induced breakdown spectroscopy (UVN + LWIR LIBS) measurement. In our attempt to study the feasibility of combining the newly developed rapid LWIR LIBS linear array detection system to existing rapid analytical techniques for a wide range of chemical analysis applications, two different solid pharmaceutical tablets, Tylenol arthritis pain and Bufferin, were studied using both a recently designed simultaneous UVN + LWIR LIBS detection system and a fast AOTF NIR (1200 to 2200 nm) spectrometer. Every simultaneous UVN + LWIR LIBS emission spectrum in this work was initiated by one single laser pulse-induced micro-plasma in the ambient air atmosphere. Distinct atomic and molecular LIBS emission signatures of the target compounds measured simultaneously in UVN (200 to 1100 nm) and LWIR (5.6 to 10 µm) spectral regions are readily detected and identified without the need to employ complex data processing. In depth profiling studies of these two pharmaceutical tablets without any sample preparation, one can easily monitor the transition of the dominant LWIR emission signatures from coating ingredients gradually to the pharmaceutical ingredients underneath the coating. The observed LWIR LIBS emission signatures provide complementary molecular information to the UVN LIBS signatures, thus adding robustness to identification procedures. LIBS techniques are more surface specific while NIR spectroscopy has the capability to probe more bulk materials with its greater penetration depth. Both UVN + LWIR LIBS and NIR absorption spectroscopy have shown the capabilities of acquiring useful target analyte spectral signatures in comparable short time scales. The addition of a rapid LWIR spectroscopic probe to these widely used optical analytical methods, such as NIR spectroscopy and UVN LIBS, may greatly enhance the capability and accuracy of the combined system for a comprehensive analysis.

The most appropriate method to preserve Bufferin 81-mg tablets dispensed for unit-dose packaging in the hospital pharmacy was examined. The surface color change of the tablets was investigated over time by spectrophotometry, and the decomposition rate of aspirin was measured by high-performance liquid chromatography (HPLC). To overcome these, it was found that we can effectively prevent color changes and preserve the quality by maintaining the humidity as 55% or less, storage with drying agent in a plastic or aluminum pack. It was revealed that the color changes became greater and the decomposition rate became higher as time passed. Color changes markedly affect the patients' compliance, and are found to be a very important factor. It was considered that the clarity of the correlation between the color change and decomposition rate may contribute to a decrease in the number of tablets discarded before the expiration date.