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Nanoparticles from Marine Biomaterials for Cancer Treatment
Published in Se-Kwon Kim, Marine Biochemistry, 2023
Alginic acid is an ideal marine biomaterial for hydrogen-structured NP construction, as it has a high degree of water solubility, high porosity, biocompatibility, and a tendency to gel under the right conditions. When counter-ions are added to ALG, sequential crosslinking and polymer network creation results in hydrogel-structured drug delivery vehicles, including microparticles and NPs (Tønnesen and Karlsen 2002). The gelification phenomenon may be controlled by the preparation techniques, resulting in the desired size ranges that are dependent on ALG concentration/viscosity, counter-ion concentration, and the speed with which the counter-ion solution is added to the alginate solution, among other parameters (Hamidi et al. 2008).
Nanomaterials in Chemotherapy
Published in D. Sakthi Kumar, Aswathy Ravindran Girija, Bionanotechnology in Cancer, 2023
P. K. Hashim, Anjaneyulu Dirisala
In a polymeric matrix composed of a three-dimensional polymer network, drugs are evenly dispersed throughout the matrix (Figure 8.5B) and do not have a membrane as a diffusion barrier. Thus, this system shows a high initial release followed by a gradual decline in the release. Polymer matrices, hydroxypropyl methylcellulose, alginates, and scleroglucan can be used as hydrophilic segments, while wax, polyethylene, polypropylene, and ethylcellulose as hydrophobic segments. Nitro-Dur I® is an example of DDS that utilizes the diffusion-controlled release of nitroglycerin drug for the treatment of angina pectoris via a transdermal patch.
Nano Delivery of Antiviral Plant Bioactives as Cancer Therapeutics
Published in Devarajan Thangadurai, Saher Islam, Charles Oluwaseun Adetunji, Viral and Antiviral Nanomaterials, 2022
Haripriya Shanmugam, Badma Priya, Manickam Senguttuvan Swetha, Janani Semalaiyappan
Diffusion-controlled release: In a core-shell NDDS, the drug molecules are encapsulated inside a core enclosed by a polymer membrane. Here, the drug release happens through dissolution of the drug inside the core, and then it is diffused through the membrane of the polymer. With the matrix type of NDDS, where plant bioactives are dispersed across a matrix of polymer network, without a polymer-membrane barrier around the drug molecules, the drug releases at a higher rate initially followed by a slower release rate.
Therapeutic applications of contact lens-based drug delivery systems in ophthalmic diseases
Published in Drug Delivery, 2023
Lianghui Zhao, Jike Song, Yongle Du, Cong Ren, Bin Guo, Hongsheng Bi
Molecular imprinting is a polymer synthesis technology that uses a template-mediated polymerization mechanism to synthesize macromolecular networks with tailored affinities, capacities, and selectivity for template molecules (White & Byrne, 2010). The drug is first polymerized with the functional monomer and then extracted after polymerization, leaving a high-affinity drug-recognition cavity in the polymer network. While reloading, drugs can bind with high-affinity cavities to increase the partition coefficient and interact with functional groups in the polymer network to reduce the diffusivity and prolong the release time (Lanier et al.,2020; Zhang et al., 2020). Currently, this technology is widely used to produce drug-loaded contact lenses with sustained release time. Tieppo et al. demonstrated that the residence time of ketotifen for imprinted lenses was 4 and 50 fold greater than non-imprinted lenses and eye drops, respectively (Tieppo et al., 2012). Omranipour et al. studied the binding and release characteristics of brimonidine imprinted soft contact lenses and found that all imprinted polymers had higher affinity for brimonidine than non-imprinted polymers, demonstrating the positive effect of the molecular imprinting technique on improving the capacity for drug loading and sustained release (Omranipour et al., 2015).
Hydrogels for localized chemotherapy of liver cancer: a possible strategy for improved and safe liver cancer treatment
Published in Drug Delivery, 2022
Jianyong Ma, Bingzhu Wang, Haibin Shao, Songou Zhang, Xiaozhen Chen, Feize Li, Wenqing Liang
Some major hydrogel classes are formed as a result of the preparation method. Following are the example of these:Homopolymeric hydrogels: Monomers are the fundamental constituents of polymer networks, and homopolymeric hydrogels are networks composed entirely of a single monomer species (Iizawa et al., 2007). Cross-linked structures can be found in homopolymers depending on the nature of their monomer and the method used for polymerization.Copolymeric hydrogels: Copolymeric hydrogels are composed of two or more distinct monomer species that contain at least one hydrophilic component. The polymer network may have a random, block, or alternating configuration (Yang et al., 2002).Multipolymer interpenetrating polymeric hydrogel (IPN), a type of hydrogel, is composed of two independent cross-linked synthetic and/or natural polymer components held together in a network form. One component of semi-IPN hydrogel is a cross-linked polymer, while the other is a non-cross-linked polymer (Maolin et al., 2000).
Design and applications of liposome-in-gel as carriers for cancer therapy
Published in Drug Delivery, 2022
Yixuan Mou, Pu Zhang, Wing-Fu Lai, Dahong Zhang
Lipid-coated hydrogels can also be stimuli-responsive. To prevent drug leakage and microgel swelling, Kiser et al. coated a drug-loaded microgel with a lipid bilayer to form lipobeads to promote permeability into the tumor vasculature (Kiser et al., 1998, 2000). During drug release, an electroporating pulse was initially used to perforate the lipid bilayer, exposing the enveloped microgel to water, causing it to swell. Electroporation and gel swelling resulted in disruption of the lipid bilayer (De Geest et al., 2006). The next step was drug release from the microgel. The properties of polymer networks conferred their responsiveness to environmental stimuli, such as temperature and pH. When the environment changes, the polymer network can also shrink like a sponge and squeeze the drugs into the space between the gel and lipid membrane, leading to drug diffusion across the lipid membrane (Kazakov, 2016). In conclusion, lipobeads maintain the advantages of liposomal drug carriers while additionally providing stronger mechanical support with better stimuli responsiveness. Furthermore, the increased stiffness conferred by complexation of the microgel greatly enhanced the cellular uptake of the lipobeads (Qin et al., 2018).