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Antiviral Nanomaterials as Potential Targets for Malaria Prevention and Treatment
Published in Devarajan Thangadurai, Saher Islam, Charles Oluwaseun Adetunji, Viral and Antiviral Nanomaterials, 2022
Kantrol Kumar Sahu, Sunita Minz, Madhulika Pradhan, Monika Kaurav, Krishna Yadav
This method involves different techniques, such as wet milling, milling media, and high-pressure homogenization for the preparation of nanoparticles (Loh et al. 2015). In wet milling, drug and excipients are suspended in a liquid medium and are milled using beads to get suspension of NPs. The nano suspension produced is subsequently dried using freeze-drying or spray drying. This technique is well suited for potent therapeutic moieties, as well as for the drugs’ high moisture content. Media milling and high-pressure homogenization are two common top-down approaches for production of drug NPs without using beads. Micro fluidizer and piston-gap homogenizer are employed for high-pressure homogenization. The size of NPs is controlled by homogenization speed, characteristic of drug, number of cycles, and temperature. This technique offers robust processing, economic, and easily scalable.
Granulation of Poorly Water-Soluble Drugs
Published in Dilip M. Parikh, Handbook of Pharmaceutical Granulation Technology, 2021
Albert W. Brzeczko, Firas El Saleh, Hibreniguss Terefe
Nanoparticle formation by piston-gap homogenizers was introduced by Müller et al. [18]. In this technology, a poorly soluble drug is dispersed in water and, by the force of a piston generating pressure up to 4000 bar, is passed through a narrow gap to affect particle reduction. Surfactants are required to facilitate size reduction and stabilize nanoparticles from ripening effects. Gap distances range from 5 to 25 μm and are dependent on the suspension viscosity. High-shear forces and turbulent flow play a role in particle reduction; however, cavitation forces are reported to have the greatest effect [19]. From Bernoulli’s law, the cross-sectional volume flow in a closed system is constant. When the liquid is in the homogenizer gap, a significant increase in dynamic pressure and a decrease in static pressure occur. The liquid starts boiling at room temperature, rapidly forming bubbles. After leaving the homogenizer gap, bubbles rapidly collapse and implode under atmospheric pressure. This cavitation process generates great energy in drug size reduction.
Rapid Isolation of Lysosomes from Cultured Cells Using a Twin Strep Tag
Published in Bruno Gasnier, Michael X. Zhu, Ion and Molecule Transport in Lysosomes, 2020
Jian Xiong, Jingquan He, Michael X. Zhu, Guangwei Du
Note: The space between the plunger and vessel varies even among the same batch of homogenizers. We strongly recommend adding water to the homogenizer to test the tightness of the homogenizer before use. Homogenizers of similar tightness should be used in order to accomplish similar yields when several lysosome samples are compared in biochemical assays.
Optimization of small RNA extraction and comparative study of NGS library preparation from low count sperm samples
Published in Systems Biology in Reproductive Medicine, 2021
Victoria Shtratnikova, Vladimir Naumov, Vitaly Bezuglov, Anna Zheludkevich, Luidmila Smigulina, Yury Dikov, Tatiana Denisova, Alexander Suvorov, J. Richard Pilsner, Russ Hauser, Stephen A. Krawetz, Oleg Sergeyev
Samples were thawed on ice. A 0.5 ml RLT buffer (Qiagen, Hilden, Germany) with 7.5 μl β-mercaptoethanol was added to the samples in the storage tube. Homogenization of cells was performed with Disruptor Genie homogenizer (Scientific Industries). Tubes with samples in RLT and 100 ug 0.2 mm RNase-free stainless steel beads (Next Advance, Troy, NY, USA) are placed in a homogenizer and shake for 5 min. Homogenate was mixed with 0.5 ml QIAzol (Qiagen, Hilden, Germany) and was homogenized for 2 min with the Disruptor Genie as above. Then, homogenate mixed with 0.22 ml of chloroform. After centrifugation (12,000 r.p.m, 4 °C, 15 min), the aqueous phase was collected and mixed with 1.5× volume of 96% ethanol and RNA was purified using the miRNeasy Mini Kit (Qiagen, Hilden, Germany) protocol (one can use RNeasy Mini Kit columns and reagents and RWT buffer for washing step) with or without DNase digestion step. Purified RNA was eluted in 30 μl of nuclease-free water (70 °C) and 1 μl of DTT and 0.5 μl of RNase Block (Agilent Technologies, Santa Clara, CA, USA) were added immediately after purification. Sample preparation reactions were performed on total RNA.
Comparison of media milling and microfluidization methods for engineering of nanocrystals: a case study
Published in Drug Development and Industrial Pharmacy, 2020
Manasi Chogale, Sandip Gite, Vandana Patravale
Homogenization methods are executed using either a microfluidizer or a piston-gap homogenizer. The microfluidizer technology used herein can generate nanoscaled particles by a frontal collision of two fluid streams under pressures up to 1700 bar [11,12]. This leads to particle collision, shear forces, and cavitation forces. The microfluidization chamber can be designed into two shapes; either Y-type or Z-type; latter being most commonly used for nanocrystal fabrication. In a Z-type interaction chamber of a microfluidizer, the incoming fluid stream is forced through numerous zigzag microchannels changing the direction of the flow leading to particle collision and the shear forces dispersing particle agglomerates and reducing particle size. Therefore, the Z-type interaction chambers are commonly used for emulsions (water-in-oil), cell disruption, deagglomeration, particle size reduction, and dispersions [13].
Scale-up production, characterization and toxicity of a freeze-dried lipid-stabilized microbubble formulation for ultrasound imaging and therapy
Published in Journal of Liposome Research, 2020
Johan Unga, Saori Kageyama, Ryo Suzuki, Daiki Omata, Kazuo Maruyama
For the larger batch preparation, a custom-made vacuum type homogenizer, Labolution Mark II 2.5 was used (Primix Corporation, Awaji, Japan) (Figure 2). The homogenizer has a mixing vessel with an 80 mm inside diameter and an operating volume of 300–500 mL of liquid. The mixing head is a rotor stator type mixer with a 30 mm stator inside diameter. The operation speed can be set in the range 500–12 000 rpm and both speed and the power input can be stored to a memory card for quality control. All parts that come in contact with the sample are fully autoclavable. Also, when all ports are closed it is completely gas-tight, allowing operation in vacuum but also that the atmosphere in the mixing vessel can be controlled so the gas phase above the liquid can be replaced and there is no risk of contamination of the sample during operation. Around the sample vessel there is a water jacket where temperature-controlled water (from ambient to 80 °C) can be flushed through to control the sample temperature. After finishing processing, the sample can be taken out through a liquid outlet with a diaphragm valve at the bottom of the vessel, allowing easy transfer of the product to any container with a minimum of risk of contamination.