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Virus-Based Nanocarriers for Targeted Drug Delivery
Published in Devarajan Thangadurai, Saher Islam, Charles Oluwaseun Adetunji, Viral and Antiviral Nanomaterials, 2022
Semra Akgönüllü, Monireh Bakhshpour, Yeşeren Saylan, Adil Denizli
These days, a general method of loading virus-based nanocarriers has been demonstrated based on CCMV. The polymer DNA amphiphile was loaded into the CCMV capsids. In this method, hydrophobic molecules are loaded into the core of the micelle (Figure 9.4a). Then, the micelles are equipped using hydrophilic molecules using hybridisation for attaching to complementary DNA strands (Figure 9.4b). At the end of the method, using an easy mixing process at neutral pH, CCMV coats protein molecules encapsulate the micelle (Kwak et al. 2010).
siRNA Delivery for Therapeutic Applications Using Nanoparticles
Published in Yashwant Pathak, Gene Delivery, 2022
Micelles are formed by self-assembly of surfactants, lipids, and aqueous insoluble polymers, and they also term as colloidal suspension. Amphiphilic molecules with hydrophobic tail and hydrophilic head having self-assembly properties create micelles upon contact with the aqueous solutions. The structure of micelles consists of an inner side containing a hydrophobic core letting the polar side remain on the outer side, providing a hollow spherical or cylindrical shape in the aqueous medium [21–23]. Micelles accompanying anti-apoptotic Bcl-2 specific siRNA and an anti-cancer drug, docetaxel (DOX), showed efficient delivery of the drug and siRNA to yield a combined RNAi-chemotherapeutic benefit against hepatic cancer. Folic acid was conjugated with the surface of the micelles for a targeting ligand of hepatic cancer cells. PEG-pp-PEI-PE nanomicelles with siRNA and paclitaxel exhibits down regulation of GFP gene and survivin compared to free drug in a lung cancer cell line. In another study, siRNA loaded in PEGylated PEI-siRNA micellar nanoparticles shows high entrapment efficiency and long-term blood circulation of siRNA with good stability. The addition of polycationic PEI was used for high loading capacity of negatively charged siRNA inside the nanoparticles.[23]
Clinical Applications of Spectral Computed Tomography
Published in Katsuyuki Taguchi, Ira Blevis, Krzysztof Iniewski, Spectral, Photon Counting Computed Tomography, 2020
Micelles are consisting of a monolayer of surfactants compared to the bilayer of phospholipids that define liposomes. They are therefore significant smaller (2–20 nm) compared to liposomes that can vary in size (20 nm–3 μm) and tend to have a hydrophobic core enabling the transport hydrophobic molecules in a hydrophilic environment compared to liposomes that can transport hydrophobic materials in between the two layers of the phospholipids and hydrophilic drugs in their core or cavity. Micelles occur naturally in the digestive tract and help to resorb otherwise non-soluble molecules. They are therefore attractive for alternative ways of drug or potential contrast agent delivery – including oral application. One of the main advantages is the relative simple and cost effective production of this nanoscale-delivery system. They have already been used for the delivery of alternative contrast agents like Bismuth into targeted structures and the resulting enhancement could be reliable detected in actual tumor tissues (16).
Arenobufagin-loaded PEG-PLA nanoparticles for reducing toxicity and enhancing cancer therapy
Published in Drug Delivery, 2023
Yang Jiaying, Sun Bo, Wei Xiaolu, Zhou Yanyan, Wang Hongjie, Si Nan, Gao Bo, Wang Linna, Zhang Yan, Gao Wenya, Luo Keke, Jiang Shan, Luo Chuan, Zhao Yu, Zhao Qinghe, Zhao Haiyu
We further investigated the biocompatibility of ArBu@PEG-PLA micelles: there was a negligible change in body weight during the 21 days of tumor therapy (Figure 4D). ArBu is known to have cardiotoxicity, and drug metabolism mainly involves the kidneys; thus, we focused here on lesions in these two major organs. These same models had histological analysis of heart and kidney to evaluate the systematic toxicity of different ArBu@PEG-PLA micelles in vivo by hematoxylin and eosin (HE) staining. Figure 5 shows the pathological analysis indicating that the cardiac muscles in tumor-bearing mice treated with free ArBu had extensive cytoplasmic vacuolization, but almost no vacuolization was observed in ArBu@PEG-PLA micelles. Thus, the low toxicity and safety of micelles were further confirmed. There was no obvious pathological damage to the kidneys in H&E staining, suggesting that the ArBu@PEG-PLA micelles were biocompatible and had low side effects during in vivo treatment.
Topical delivery of pluronic F127/TPGS mixed micelles-based hydrogel loaded with glycyrrhizic acid for atopic dermatitis treatment
Published in Drug Development and Industrial Pharmacy, 2021
Chengying Shen, Baode Shen, Junjun Zhu, Hailong Yuan, Jianxin Hu
Both of GL-sol–gel and the optimized GL-MMs-gel exhibited a sustained-release behavior. This may be due to the three-dimensional network structure of the gel that could hinder the release of GL. The cumulative release of GL from GL-MMs-gel was significantly lower than that of GL-sol–gel at the end of 24 h. This could be attributed to the structural stability of the micelles, which made it difficult for the drug to escape easily from the core of the micelles, leading to a sustained release of GL [24]. Different from the in vitro drug release, the skin permeation and deposition of GL were significantly enhanced after loading into MMs-gel as compared to GL-sol–gel. This may be mainly attributed to skin penetration enhancing effect of micelles. It was reported that drug-loaded micelles tended to first accumulate in skin appendages such as hair follicle during the permeation process, which could serve as a reservoir from which the drug could infiltrate into different skin layers [43–45]. After micelles segregating, the TPGS and F127 could act as penetration enhancers that increase the permeability of GL across the skin [46–48]. In addition, the skin hydration of hydrogel could also lead to increased skin permeability and drug transport [49,50].
Therapeutic nanocarriers comprising extracellular matrix-inspired peptides and polysaccharides
Published in Expert Opinion on Drug Delivery, 2021
Lucas C. Dunshee, Millicent O. Sullivan, Kristi L. Kiick
Micelles are just one of the many types of nanocarriers that have commonly been studied in modern drug delivery strategies. Generally, micelles are self-assembled aggregates that are comprised of amphiphilic molecules such as lipids or synthetic polymers, but can be composed of appropriately designed ELPs as well. The most common strategy for making ELP-based micelles is to increase the hydrophobicity of the guest residue of the common (VPGXAAG)n repeat in one portion of the ELP (e.g. toward the N-terminus), while encoding more hydrophilic guest residues in the other portion of the ELP (e.g. toward the C-terminus), to yield a single amphiphilic molecule (i.e. a diblock-ELP polymer). Figure 2 illustrates schematic representations of such ELP micelles as individual molecules of diblock-ELPs (Figure 2 (a) and self-assembled micelles (Figure 2 (a,b) [29,30]. Each block of the diblock-ELP has its own Tt, and the micelle self-assembly process typically requires the hydrophobic block of the diblock-ELP to selectively collapse and self-aggregate via heating to temperatures above the Tt of the hydrophobic block while still maintaining a temperature that is less than the Tt of the hydrophilic block [31], so that the hydrophobic block forms the core and the hydrophilic block forms the corona of the micelle. The lowest Tt value at which micellization occurs is known as the critical micelle temperature (CMT) [31].