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Drug Substance and Excipient Characterization
Published in Dilip M. Parikh, Handbook of Pharmaceutical Granulation Technology, 2021
Parind M. Desai, Lai Wah Chan, Paul Wan Sia Heng
In photon correlation spectroscopy, fluctuations in the scattered light intensity are determined. These fluctuations are due to the Brownian motion of the test particles suspended in a liquid medium. Larger particles will move more slowly than smaller ones and therefore, the rate of decay in intensity of the scattered light at a particular measuring point will depend on the size of the particle. The particle size distribution is computed using complex calculations based on the different intensity of scattered light (normally at 90° to the incident beam) and rate of decay. Multiple angle measurements are sometimes applied to improve the quality of the size parameters obtainable. Although there has been much development in the field of nanosizing, including real-time direct observation and measurements based on diffusion, these techniques determine particles that are not in the size range commonly encountered in larger scale product manufacture.
Best Practices in Cancer Nanotechnology: Perspective from NCI Nanotechnology Alliance *
Published in Valerio Voliani, Nanomaterials and Neoplasms, 2021
William C. Zamboni, Vladimir Torchilin, Anil K. Patri, Jeff Hrkach, Stephen Stern, Robert Lee, Andre Nel, Nicholas J. Panaro, Piotr Grodzinski
Regulatory agencies are becoming increasingly stringent about characterization of the particle size distribution of nanotechnology-based products. Because the particle size distribution may have a significant influence on the biodistribution and biologic efficacy of the formulation, this parameter is critical to measure and track. This task is not trivial and needs to be well understood to generate meaningful and actionable data. A review of particle size analysis is beyond the scope of this article, and the reader is referred to the literature [83].
Technetium-Labeled Compounds
Published in Garimella V. S. Rayudu, Lelio G. Colombetti, Radiotracers for Medical Applications, 2019
Suresh C. Srivastava, Powell Richards
Whereas the H2S method provides an essentially monodisperse colloidal preparation containing particles (90%) with a size (diameter) of 0.09 ± 0.01 μ m,355 the thiosulfate method gives a more nonuniform size distribution of the colloid when prepared using commercially available kits. Using nucleopore filtration, Davis et al.371 determined the size distribution of the particles to be as follows: <0.1 μ m (15%); <0.4 μ m (70%); 0.1 to 1.0 μ m (80%); >1.0 μ m (5%). A number of commercial kits were used in this study and they all provided essentially similar size distribution data. Other recent studies utilizing various techniques have also given corresponding results on the particle size distribution.372,373 For routine imaging of the liver and spleen, use of the thiosulfate colloid is quite satisfactory; availability of several kits for this purpose greatly adds to its convenience.
Intra-articular drug delivery systems for osteoarthritis therapy: shifting from sustained release to enhancing penetration into cartilage
Published in Drug Delivery, 2022
Huirong Huang, Zijian Lou, Shimin Zheng, Jianing Wu, Qing Yao, Ruijie Chen, Longfa Kou, Daosen Chen
While the particle size affects the penetration depth, size distribution affects osmotic dose. Enough drug particles are required to reach the drug target to get satisfactory curative effects. If particle size distribution is too wide, the number of particles with the appropriate size reduces, and fewer particles reach the drug target. An increase in dosage may solve this problem but is likely to be associated with adverse reactions. Consequently, improving the homogeneity of drug particles is the best way to ensure adequate drug concentration and reduce the probability of adverse reactions. Therefore, there is a need to develop technology for preparing homogeneous particles. Ansboro et al. were able to prepare homogeneous nanoparticles using a sulfonated polystyrene template, thus enhancing curative effects (Ansboro et al., 2014).
Characterization and pharmacokinetic evaluation of microcomposite particles of alpha lipoic acid/hydrogenated colza oil obtained in supercritical carbon dioxide
Published in Pharmaceutical Development and Technology, 2020
Masatoshi Honjo, Okuhara Yasuhide, Masayoshi Yamada, Sei Higuchi, Kenji Mishima, Tanjina Sharmin, Taku Michael Aida, Takafumi Kato, Makoto Misumi, Tadashi Suetsugu, Hideaki Orii, Keiichi Irie, Kazunori Sano, Kenichi Mishima, Tomomitsu Satho, Takunori Harada
The surface morphology of the particles observed by SEM is shown in Figure 3. The particle-size distribution determined by a particle size analyzer is as follows. The median diameter (D 50) of pure HCO and ALA bulk powder were 60.9 and 57.1 μm, respectively (Figure 3(a,b)). The ALA/HCO/SCP (Figure 3(c)) had a particle diameter of 0.71 μm (D 10) and 6.6 μm (D 90) with a median diameter of 3.2 μm. The MC-50F particles had a particle diameter of 12.1 μm (D 10) to 363.1 μm (D 90) with a median diameter of 88.1 μm (Figure 3(d)). The particle-size distribution of HCO, ALA bulk powder, ALA/HCO/SCP and MC-50F particles are presented in Supplementary Figure (S1). The median diameter of ALA/HCO/SCP particles produced by modified PGSS is about one twentieth smaller than that of MC-50F particles. This size effect of ALA/HCO/SCP and MC-50F particles will appear in the difference in the pharmacokinetic parameters such as Cmax refers to the maximum drug concentration after the administration of the drugs.
Stimuli-responsive polyvinylpyrrolidone-NIPPAm-lysine graphene oxide nano-hybrid as an anticancer drug delivery on MCF7 cell line
Published in Artificial Cells, Nanomedicine, and Biotechnology, 2019
Maryam Ashjaran, Mirzaagha Babazadeh, Abolfazl Akbarzadeh, Soodabeh Davaran, Roya Salehi
To characterize the size distribution of particles (such as polymers, micelles, vesicles, nanoparticles, etc.) in suspension, dynamic light scattering (DLS) technique was used. The determined size in this method is depend on several factors including particle core, size of surface, particle concentration and type of media. In this regard, we aimed to determine size of our designed GO/NHs in PBS solution (simulated condition of body) at very low concentration about 20 ppm. As seen in Figure 5, the DLS diagram displayed two particle population at two different diameters and intensity (14.8% for peak 1 and 85.2% for peak 2) and it is showed that the prepared drug carrier has relatively monodispersed. The particle size distribution is about 37 nm which is suitable for drug delivery systems with capability of internalization into the cells.