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Bio-Implants Derived from Biocompatible and Biodegradable Biopolymeric Materials
Published in P. Mereena Luke, K. R. Dhanya, Didier Rouxel, Nandakumar Kalarikkal, Sabu Thomas, Advanced Studies in Experimental and Clinical Medicine, 2021
Kumar et al. [16] have developed a green route to pegylated amphiphilic polymers with the use of immobilized enzyme, Candida Antarctica lipase B. The ability of these polymers to form the nano-micelles makes them suitable for application in drug delivery systems and in cancer diagnostics. Gong et al. [17] developed a new highly innovative two-photon activated photodynamic therapy (PDT) which has three-fold level of application, (a) a photosensitizer: a porphyrin substituted on the meso positions by chromophores with large two-photon absorption and activated in the near infra-red region in the tissue transparency window and efficiently producing singlet oxygen as the cytotoxic agent; (b) which can target small molecule also target receptor sites on the tumor; and (c) a imaging agent near IR that can correctly give image of the tumor for treatment. Adronov et al. [14] synthesized carborane functionalized dendronized polymers and found them to be useful as potential boron neutron capture therapy (BNCT) agents. Nederberg and coworkers [18] have developed a series of telechelic biodegradable ionomers based on poly(trimethylene carbonate) carrying zwitterionic, anionic, or cationic functional groups for protein drug delivery. Biodegradable ionomers was utilized for protein loading simply by letting the material swell in an aqueous protein solution. The process can be done either directly after loading or after a drying. Protein activity is maintained suggesting that these ionomers may favorably interact with guest proteins and denaturation is suppressed.
Gold Nanomaterials at Work in Biomedicine *
Published in Valerio Voliani, Nanomaterials and Neoplasms, 2021
Xuan Yang, Miaoxin Yang, Pang Bo, Madeline Vara, Younan Xia
It is worth mentioning that a secondary tethering of molecules to the thiolate ligands is possible either through covalent conjugation (e.g., amine-carboxylate coupling [286] or click chemistry [37, 287]) or noncovalent interactions (e.g., electrostatic interactions [288, 289] or hydrophobic interactions [290]). For example, Astruc, Hosmane, and coworkers demonstrated the preparation of dendritic PEGylated Au nanoparticle-carborane assemblies through click chemistry between azido-terminated Au nanoparticles and a mixture of carborane alkyne and PEG alkyne [287]. Such Au nanostructures may find application in boron neutron capture therapy (BNCT) due to the presence of carboranes. Rotello and coworkers reported the preparation of a Au-enzyme conjugated structure via electrostatic interactions between negatively charged β-galactosidase and positively charged trimethylammonium PEGylated Au nanoparticles [289]. Upon the addition of toluene and 1,2,4-trichlorobenzene, microcapsules composed of nanoparticle-enzyme conjugates were formed. The secondary tethering of Au nanostructures is often used in sensing, drug loading, and improving the biodistribution of such nanomaterials.
Neutron Capture Therapy of Cancer: Nanoparticles and High Molecular Weight Boron Delivery Agents
Published in Mansoor M. Amiji, Nanotechnology for Cancer Therapy, 2006
Gong Wu, Rolf F. Barth, Weilian Yang, Robert J. Lee, Werner Tjarks, Marina V. Backer, Joseph M. Backer
An alternative method to deliver boron compounds by means of dendrimers is to incorporate carborane cages within the dendrimer (Figure 6.5). Matthew et al. have reported that 4, 8, or 16 carboranes could be inserted into an aliphatic polyester dendrimer by means of a highly effective synthon, a bifunctional carborane derivative with an acid group and a benzyl ether protected alcohol.96 The procedure employed a divergent synthesis with high yield. The resulting polyhydroxylated dendrimer was WS with a minimum ratio of eight hydroxyl groups per carborane cage. Carborane containing dendrimers potentially could be used as boron delivery agents for BNCT because it is possible to control the number of carborane moieties and overall solubility.
Carboranyl-1,8-naphthalimide intercalators induce lysosomal membrane permeabilization and ferroptosis in cancer cell lines
Published in Journal of Enzyme Inhibition and Medicinal Chemistry, 2023
Sebastian Rykowski, Dorota Gurda-Woźna, Agnieszka Fedoruk-Wyszomirska, Marta Orlicka-Płocka, Aleksandra Kowalczyk, Paweł Stączek, Marta Denel-Bobrowska, Katarzyna Biniek-Antosiak, Wojciech Rypniewski, Eliza Wyszko, Agnieszka B. Olejniczak
Several studies have reviewed the application of carboranes (isomers of dicarba-closo-dodecaborane) in medicinal chemistry, describing their derivatives as carriers for boron neutron capture therapy and as unique three-dimensional pharmacophores or modulators, thus indicating that carboranes are still an emerging class of compounds. Due to the distinct physical and chemical properties of carboranes, their derivatives with better or new anticancer, antibacterial, antiviral, and nematicidal activities, among others, have been designed14–23. The properties that are critical for the application of carboranes in medicinal chemistry are as follows: their ability to form unique noncovalent interactions with biological targets; spherical or ellipsoidal geometry and rigid 3 D arrangement to build 3 D constructions; lipophilicity, amphiphilicity, or hydrophilicity (depending on the type of the boron cluster used); adjustable pharmacokinetics, bioavailability, bio-orthogonality, and stability in biological environments; and a decreased susceptibility to metabolism14,15.
The structural basis for the selectivity of sulfonamido dicarbaboranes toward cancer-associated carbonic anhydrase IX
Published in Journal of Enzyme Inhibition and Medicinal Chemistry, 2020
Michael Kugler, Josef Holub, Jiří Brynda, Klára Pospíšilová, Suzan El Anwar, Dmytro Bavol, Miroslav Havránek, Vlastimil Král, Milan Fábry, Bohumír Grüner, Pavlína Řezáčová
Various strategies have emerged to overcome the specificity problem18–20 and we have recently contributed to this effort by introducing dicarbaborane (with the broadly used trivial name carboranes) clusters as three-dimensional pharmacophores in sulfonamide and sulfamide CA inhibitors21,22. Unlike planar compounds, carboranes possess a three-dimensional pharmacophore providing necessary hydrophobic interactions for filling hydrophobic cavities, and their role in the design of pharmacologically relevant molecules has been firmly established23–33. Carboranes are non-toxic abiotic compounds that can increase interaction energy and have good in vivo stability and bioavailability24,34.
Icosahedral boron clusters as modifying entities for biomolecules
Published in Expert Opinion on Biological Therapy, 2018
Tomasz M. Goszczyński, Krzysztof Fink, Janusz Boratyński
Carbonic anhydrases (CAs) are zinc metalloenzymes. Different CA isozymes play an important role in various pathological processes (e.g., the carbonic anhydrase isozyme IX (CAIX) is tumor associated). Usually, CA inhibitors contain a sulfonamide or sulfamide group that is responsible for coordination to the zinc cation in the CA catalytic site [40]. Most traditional CA inhibitors lack selectivity, which leads to numerous side effects. Based on a structural analysis of CAII in complex with numerous inhibitors [41], Brynda et al. hypothesized that CA inhibitors could be designed more effectively based on three-dimensional scaffolds rather than flat structures [42]. Series of CA inhibitors with four different carborane cluster types were studied: two carboranes (C2B10H12), one monocarborane (CB11H12) and one nido-carborane (C2B9H12). Carborane clusters filled the enzyme active site well and formed both polar and van der Waals interactions with its amino acid residues [42,43]. Compounds containing carborane showed the best inhibitory activity toward CAII and CAIX isozymes (Ki value of 0.7 μM and 0.38 μM, respectively). Compounds containing monocarborane were less efficient but more selective inhibitors (Ki value of 8.6 μM and 2.2 μM for CAII and CAIX isozymes, respectively). Compounds containing nido-carborane had even weaker inhibitor activity than carborane derivatives. However, due to their smaller size, these had the possibility to adjust their position within the active site. This allows the accommodation of additional substituents that might improve selectivity toward CA isozymes. Furthermore, compounds containing nido-carboranes will have a higher solubility than those containing closo-carboranes.