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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
Traditional flow and bulk property evaluation techniques such as shear tests discussed earlier do not consider dynamic conditions experienced by powder passing through various unit operations. Techniques are now available (e.g., FT4, Freeman Technology - Micromeritics, Tewkesbury, UK) to analyze powder flow in dynamic conditions as a function of strain rate [41]. Dynamic flow analysis indicators, such as basic flow energy (BFE), stability index (SI), flow rate index (FRI), and specific energy (SE) can be derived on the basis of these tests. In this technique, an impeller with a twisted blade rotates at a specific tip speed and penetrates in and out of the powder bed filled in a vessel. The first step of “conditioning methodology” is discussed in section 3.2. In the next step, the blade penetrates again into the conditioned powder bed filled with force while rotating anti-clockwise. This bulldozing blade action compacts the bed and applies normal stresses through the blade. Axial force (F) required for downward blade movement and torque required for blade rotation (T) are measured. Total input work (E), also called “flow energy,” of the powder is computed using F and T values as shown below [74].where R is the radius of the blade, α is the helix angle, and H is the penetrated depth.
Drug Delivery Systems for the Controlled Delivery of Berberine
Published in Madhu Gupta, Durgesh Nandini Chauhan, Vikas Sharma, Nagendra Singh Chauhan, Novel Drug Delivery Systems for Phytoconstituents, 2020
Rosario Pignatello, Simona Cianciolo, Agata K. Giuffrida
The micromeritics and drug loading data of freeze-dried microparticles were analyzed, as well as the chemical interactions of BER with the Eudragit® polymers in the solid-state. BER was encapsulated with high yields in all the prepared batches (Table 14.2), regardless of the variables used for their production. In terms of mean particle size, we observed that the only formulation variable that affected this parameter was the copolymer composition, with the ERL/ERS 30:70 blends that generally gave smaller and more homogeneous microparticle populations (cf. Table 14.2).
Effects of titanium dioxide nanoparticles on nutrient absorption and metabolism in rats: distinguishing the susceptibility of amino acids, metal elements, and glucose
Published in Nanotoxicology, 2020
Yanjun Gao, Yixuan Ye, Jing Wang, Hao Zhang, Yao Wu, Yihui Wang, Lailai Yan, Yongliang Zhang, Shumin Duan, Lizhi Lv, Yun Wang
Two kinds of food additives, powder-form titanium dioxide particles (N-TiO2, M-TiO2), were purchased from Shanghai Aladdin Reagent Co. Ltd, Shanghai, China. The size and shape of the particles were characterized by transmission electron microscopy (TEM, JEM-200CX, JEOL, Tokyo, Japan) and scanning electron microscopy (SEM, JSM-7401F, JEOL, Tokyo, Japan). The crystal structure of the particles was identified by X-ray powder diffraction (XRD, X'Pert PRO, PANalytical, Eindhoven, Netherlands). The specific surface area (SSA) of the particles was measured according to the Brunauer–Emmett–Teller (BET) method (ASAP 2020, Micromeritics, Norcross, US). The particle hydrodynamic diameters, polydispersity index, and zeta potential in ultrapure water (H2O), artificial gastric juice (AGJ), and artificial intestinal juice (AIJ) were tested using a ZetaSizer Nano ZS90 (Malvern Instruments Ltd, Malvern, UK), and the methods of preparing AGJ and AIJ were according to our previous work (Wang et al. 2013). The purity and impurities of the particles, and the ion release of the particles in H2O, AGJ, and AIJ were analyzed by inductively coupled plasma mass spectrometry (ICP-MS, Elan DRC II, PerkinElmer, Waltham, US).
Mechanics of tablet formation: a comparative evaluation of percolation theory with classical concepts
Published in Pharmaceutical Development and Technology, 2019
Saurabh M. Mishra, Bhagwan D. Rohera
True density of the powder materials was determined using a gas pycnometer (AccuPyc® II 1340, Micromeritics Instruments Corp., Norcross, GA). The pycnometer allows nondestructive measurement of volume and density of powder and solid materials, and uses a gas displacement technique to determine the volume of the sample under test. An inert gas (helium) was used as the displacement medium. Pycnometer was calibrated with an iron sphere of known mass prior to each measurement. For the determination, a known weight of powder sample was transferred into an aluminum sample container of 3.5 cm3 volume, and helium gas was passed through the sample from the reservoir. The determinations were carried out at room temperature. The instrument automatically purges moisture and volatile materials from the powder sample and repeats the analysis until successive measurements yield consistent results. The determination of sample density was repeated for up to 10 cycles. The average reading of 10 cycles was recorded as the true density of the material.
Polyethylene glycol-coated porous magnetic nanoparticles for targeted delivery of chemotherapeutics under magnetic hyperthermia condition
Published in International Journal of Hyperthermia, 2019
Ali Dabbagh, Ziba Hedayatnasab, Hamed Karimian, Masoud Sarraf, Chai Hong Yeong, Hamid Reza Madaah Hosseini, Noor Hayaty Abu Kasim, Tin Wui Wong, Noorsaadah Abdul Rahman
The particles morphology and size were investigated using a transmission electron microscope (TEM; LEO Libra 120 kV, Carl Zeis AG, Oberkochen, Germany). Dynamic light scattering (Malvern Instruments, Malvern, UK) was employed to determine the size distribution of the produced particles as well as their zeta potential at pH 7.0. The surface area of the particles was also measured by Brunauer–Emmett–Teller approach (ASAP2020, TRISTAR II 3020 Kr, Micromeritics Instruments, Norcross, GA, USA). The magnetic characteristics of the synthesized nanoparticles were investigated using vibrated sample magnetometer (model 7400 series, Lakeshore, Chicago, IL). In order to calculate the onset phase transition temperature of PEG1500, differential scanning calorimetry (DSC820 with TSO 801RO robot, Mettler-Toledo, Columbus, OH, USA) with scan rate of 5 °C·min−1 was used. Thermogravimetric analysis (TGA; TGA/SDTA 851e, Mettler-Toledo, Greifensee, Switzerland) was also performed to calculate the weight percentage of the polymeric shell.