Wagh M P, Sonawane Y H, Joshi O U
NDMVPS's College of Pharmacy, Department of Pharmaceutics, Shivajinagar, Gangapur Road, Nashik-422 002, India.
Indian J Pharm Sci. 2009 May;71(3):235-41. doi: 10.4103/0250-474X.56014.
The terahertz gap has a frequency ranges from approximately 0.3 THz to approximately 10 THz in the electromagnetic spectrum which is in between microwave and infrared. The terahertz radiations are invisible to naked eye. In comparison with x-ray they are intrinsically safe, non-destructive and non-invasive. Terahertz spectroscopy enables 3D imaging of structures and materials, and the measurement of the unique spectral fingerprints of chemical and physical forms. Terahertz radiations are produced by a dendrimer based high power terahertz source and spectroscopy technologies. It resolves many of the questions left unanswered by complementary techniques, such as optical imaging, Raman and infrared spectra. In the pharmaceutical industries it enables nondestructive, internal, chemical analysis of tablets, capsules, and other dosage forms. Tablet coatings are a major factor in drug bioavailability. Therefore tablet coatings integrity and uniformity are of crucial importance to quality. Terahertz imaging gives an unparalleled certainty about the integrity of tablet coatings and the matrix performance of tablet cores. This article demonstrates the potential of terahertz pulse imaging for the analysis of tablet coating thickness by illustrating the technique on tablets.
太赫兹波段在电磁频谱中频率范围约为0.3太赫兹至10太赫兹，介于微波和红外之间。太赫兹辐射肉眼不可见。与X射线相比，它们本质上是安全的，具有非破坏性和非侵入性。太赫兹光谱能够对结构和材料进行三维成像，并测量化学和物理形态的独特光谱指纹。太赫兹辐射由基于树枝状大分子的高功率太赫兹源和光谱技术产生。它解决了许多互补技术（如光学成像、拉曼光谱和红外光谱）未解答的问题。在制药行业，它能够对片剂、胶囊和其他剂型进行无损内部化学分析。片剂包衣是药物生物利用度的一个主要因素。因此，片剂包衣的完整性和均匀性对质量至关重要。太赫兹成像能为片剂包衣的完整性和片芯的基质性能提供无与伦比的确定性。本文通过在片剂上展示该技术，证明了太赫兹脉冲成像在分析片剂包衣厚度方面的潜力。
