Manufacturing and Assessing the New Orally Disintegrating Tablets, Containing Nimodipine-hydroxypropyl-ß-cyclodextrin and Nimodipine-methyl-ß-cyclodextrin Inclusion Complexes.

The aim of the present study was to manufacture new orally disintegrating tablets containing nimodipine-hydroxypropyl-ß-cyclodextrin and nimodipine-methyl-ß-cyclodextrin inclusion complexes. For obtaining a better quality of the manufactured tablets, three methods of the preparation of inclusion complexes, in a 1:1 molar ratio, were used comparatively; namely, a solid-state kneading method and two liquid state coprecipitation and lyophilization techniques. The physical and chemical properties of the obtained inclusion complexes, as well as their physical mixtures, were investigated using Fourier transformed infrared spectroscopy, scanning electron microscopy, X-ray diffraction analyses, and differential scanning calorimetry. The results showed that the lyophilization method can be successfully used for a better complexation. Finally, the formulation and precompression studies for tablets for oral dispersion, containing Nim-HP-ß-CD and Nim-Me-ß-CD inclusion complexes, were successfully assessed.

Design and Evaluation of Orally Dispersible Tablets Containing Amlodipine Inclusion Complexes in Hydroxypropyl-ß-cyclodextrin and Methyl-ß-cyclodextrin.

The development of new orally dispersible tablets containing amlodipine (AML) inclusion complexes in hydroxypropyl-ß-cyclodextrin (HP-ß-CD) and in methyl-ß-cyclodextrin (Me-ß-CD) was studied. The methods of obtaining amlodipine and the physical and chemical properties of the inclusion complexes using the two cyclodextrins was investigated separately. Solid inclusion complexes were obtained by three methods: kneading, coprecipitation, and lyophilization, at a molar ratio of 1:1. For comparison, a physical mixture in the same molar ratio was prepared. The aim of the complexation process was to improve the drug solubility. As the lyophilization method leads to a complete inclusion of the drug in the guest molecule cavity, for both used cyclodextrins, these types of compounds were selected as active ingredients for the design of orally dispersible tablets. Subsequently, the formulation of the orodispersible tablets containing AML-HP-ß-CD and AML-Me-ß-CD inclusion complexes and quality parameters of the final formulation were evaluated. The results prove that F1 and F4 formulations, based on silicified microcrystalline cellulose, which contains insignificant proportions of very small or very large particles, had the lowest moisture degree (3.52% for F1 and 4.03% for F4). All of these demonstrate their porous structure, which led to good flowability and compressibility performances. F1 and F4 formulations were found to be better to manufacture orally dispersible tablets.

Formation and Physico-Chemical Evaluation of Nifedipine-hydroxypropyl-ß-cyclodextrin and Nifedipine-methyl-ß-cyclodextrin: The Development of Orodispersible Tablets.

The novelty in this study is the development of new orodispersible tablets containing nifedipine (NIF) as the active ingredient. Initially, the formation of inclusion complexes between nifedipine and two derivatives of beta-cyclodextrin, namely, hydroxypropyl-ß-cyclodextrin (HP-ß-CD) and methyl-ß-cyclodextrin (Me-ß-CD), was established. Inclusion complexes of nifedipine were prepared by different procedures: kneading, coprecipitation and lyophilization methods, using a 1:1 molar ratio among the drug and cyclodextrin compounds. A physical mixture was also developed for comparison, with the same molar ratio. The physicochemical and structural properties of these obtained complexes were subsequently analysed using Fourier-transform infrared spectroscopy, scanning electron microscopy, differential scanning calorimetry and X-ray diffraction techniques. The lyophilization method of preparation leads to obtaining the complete inclusion of nifedipine in the used cyclodextrin cavity, for both the derivative cyclodextrins. After that, preformulation studies and manufacturing of orodispersible tablets containing NIF-HP-ß-CD and NIF-Me-ß-CD, respectively, inclusion complexes were advanced. The obtained findings show that only F3 (which contains NIF-HP-ß-CD) and F6 (which contains NIF-Me-ß-CD) have a suitable flowability for the direct compression materials.

Bioacoustics response of small benign or malignant nodules.

One of the most important features of separation between benign or malignant tissues is their smooth or rough shape. This article presents a new method for early diagnosis of thyroid cancer by knowing the resonance frequencies of a certain tissue. Two types of nodules were investigated: spherical and elliptical. Their external surfaces were smooth or rough with different values of spicules. Propagation of sound through the human body was modeled by a classical partial differential equation associated with Neumann or Dirichlet boundary conditions. The assessments of about ten acoustic eigenfrequencies are enough to decide the type of external surfaces: smooth or rough, or whether nodule is benign or malignant. Data obtained by this method refers to the result of investigating 3D bodies smaller than 5 mm, when other medical devices such as ultrasound or CT cannot evaluate their surface shape because of their limited spatial resolution.