Horseradish peroxidase-catalyzed hydrogelation for biomedical applications

2018 ◽  
Vol 6 (6) ◽  
pp. 1286-1298 ◽  
Author(s):  
Mehdi Khanmohammadi ◽  
Mahsa Borzouyan Dastjerdi ◽  
Arman Ai ◽  
Akbar Ahmadi ◽  
Arash Godarzi ◽  
...  

Hydrogels catalyzed by horseradish peroxidase (HRP) serve as an efficient and effective platform for biomedical applications due to their mild reaction conditions for cells, fast and adjustable gelation rate in physiological conditions, and an abundance of substrates as water-soluble biocompatible polymers.

2019 ◽  
Vol 25 (34) ◽  
pp. 3608-3619 ◽  
Author(s):  
Uzma Arif ◽  
Sajjad Haider ◽  
Adnan Haider ◽  
Naeem Khan ◽  
Abdulaziz A. Alghyamah ◽  
...  

Background: Biocompatible polymers are gaining great interest in the field of biomedical applications. The term biocompatibility refers to the suitability of a polymer to body and body fluids exposure. Biocompatible polymers are both synthetic (man-made) and natural and aid in the close vicinity of a living system or work in intimacy with living cells. These are used to gauge, treat, boost, or substitute any tissue, organ or function of the body. A biocompatible polymer improves body functions without altering its normal functioning and triggering allergies or other side effects. It encompasses advances in tissue culture, tissue scaffolds, implantation, artificial grafts, wound fabrication, controlled drug delivery, bone filler material, etc. Objectives: This review provides an insight into the remarkable contribution made by some well-known biopolymers such as polylactic-co-glycolic acid, poly(ε-caprolactone) (PCL), polyLactic Acid, poly(3- hydroxybutyrate-co-3-hydroxyvalerate) (PHBV), Chitosan and Cellulose in the therapeutic measure for many biomedical applications. Methods: : Various techniques and methods have made biopolymers more significant in the biomedical fields such as augmentation (replaced petroleum based polymers), film processing, injection modeling, blow molding techniques, controlled / implantable drug delivery devices, biological grafting, nano technology, tissue engineering etc. Results: The fore mentioned techniques and other advanced techniques have resulted in improved biocompatibility, nontoxicity, renewability, mild processing conditions, health condition, reduced immunological reactions and minimized side effects that would occur if synthetic polymers are used in a host cell. Conclusion: Biopolymers have brought effective and attainable targets in pharmaceutics and therapeutics. There are huge numbers of biopolymers reported in the literature that has been used effectively and extensively.


2020 ◽  
Vol 9 (1) ◽  
pp. 1118-1136
Author(s):  
Zhenjia Huang ◽  
Gary Chi-Pong Tsui ◽  
Yu Deng ◽  
Chak-Yin Tang

AbstractMicro/nano-fabrication technology via two-photon polymerization (TPP) nanolithography is a powerful and useful manufacturing tool that is capable of generating two dimensional (2D) to three dimensional (3D) arbitrary micro/nano-structures of various materials with a high spatial resolution. This technology has received tremendous interest in cell and tissue engineering and medical microdevices because of its remarkable fabrication capability for sophisticated structures from macro- to nano-scale, which are difficult to be achieved by traditional methods with limited microarchitecture controllability. To fabricate precisely designed 3D micro/nano-structures for biomedical applications via TPP nanolithography, the use of photoinitiators (PIs) and photoresists needs to be considered comprehensively and systematically. In this review, widely used commercially available PIs are first discussed, followed by elucidating synthesis strategies of water-soluble initiators for biomedical applications. In addition to the conventional photoresists, the distinctive properties of customized stimulus-responsive photoresists are discussed. Finally, current limitations and challenges in the material and fabrication aspects and an outlook for future prospects of TPP for biomedical applications based on different biocompatible photosensitive composites are discussed comprehensively. In all, this review provides a basic understanding of TPP technology and important roles of PIs and photoresists for fabricating high-precision stimulus-responsive micro/nano-structures for a wide range of biomedical applications.


2001 ◽  
Vol 675 ◽  
Author(s):  
Jeong-Seo Park ◽  
Han-Chang Kang ◽  
Kurt E. Geckeler

ABSTRACTAs [60]fullerene is a very hydrophobic macromolecule, there have been a number of attempts to make it more hydrophilic for biomedical applications. By attaching hydrophilic moieties such as poly(oxyethylene)(POE) chains and cyclodextrin molecules to [60]fullerene, novel water-soluble and biocompatible materials have been successfully prepared [1,2].The synthesis of novel macrocyclic fullerene conjugates which are water-soluble is reported. The telechelic fullerene derivatives have been prepared via addition reaction of POE-based arms with covalently bonded β-cyclodextrin (CD) to [60]fullerene. To this end, a mono-tosylated CD derivative has been prepared in pyridine and then reacted with an amino-functional POE in the presence of triethylamine. The subsequent reaction of [60]fullerene with the hydrophilic POE-conjugated CD-derivative yielded the macrofullerene after separation and purification procedures.The macrocyclic [60]fullerene derivatives obtained were soluble in water and characterized by UV-VIS and FT-IR spectroscopy as well as light scattering measurements and thermogravimetric analysis.


1998 ◽  
Vol 530 ◽  
Author(s):  
T. Schiimstel ◽  
H. Schirra ◽  
J. Gerwann ◽  
C. Lesniak ◽  
A. Kalaghi-Nafchi ◽  
...  

AbstractCommercially available and synthesized silica particles were fluorescently labeled with FITC and modified to get a wide variety of particle systems with defined size and surface charge. By a variation of reaction conditions particles with diameters of 10 and 80 nm determined with TEM and with zetapotentials between -50 to +30 mV under physiological conditions (pH: 7.4, PBS-buffer) were available.A further molecular shell consisiting of avidin was obtained by binding the molecules to negatively charged particle surfaces through electrostatic interactions. The amount of avidin coupled to the silica particles was 1.7 μg per mg particle. Starting with particles with an hydrodynamic diameter determined with PCS of 260 nm, the size increased to 500 nm, while the zeta potential was altered to -8 mV under physiological conditions.Biotinylated wheat germ agglutinin (bio-WGA) can be bonded to such particles through avidin / biotin complex formation. Up to 2.8 μg lectin per mg particles could be coupled to the particle surface. This leads to a further increase of hydrodynamic diameter to 650 nm. It could be shown by hemagglutination test, that the bonded lectin is still active. No toxic effects of the silica particles were found at 1 wt.-% particle concentration with various cell types (Caco-2, L132). The binding of lectin-particle complexes to cells was increased by a factor of 4.4 in comparison to uncoated particles.In addition it was found that WGA can directly be coupled to the particle surface. An amount of 1.8 μg Lectin per mg particle was determined. The hydrodynamic diameter increases from 260 nm to 432 rm, while a zetapotential of-28 mV was found under physiological conditions.It could be shown, that negatively charged silica nanoparticles are suitable systems to couple various biomolecules retaining their biological function.


Author(s):  
Rajiv Sharma ◽  
Vikram Jeet Singh ◽  
Pooja A Chawla

Background: The platinum (II) complexes as anticancer agents have been well explored for the development of novel analogs. Yet, none of them achieved clinical importance in oncology. At present, anticancer compounds containing platinum (II) complexes have been employed in the treatment of colorectal, lung, and genitourinary tumors. Among the platinum-based anticancer drugs, Cisplatin (cis-diamine dichloroplatinum (II), cis-[Pt(NH3)2Cl2]) is one of the most potent components of cancer chemotherapy. The nephrotoxicity, neurotoxicity and ototoxicity, and platinum compounds associated resistant cancer are some major disadvantages. Objective: With the rapidly growing interest in platinum (II) complexes in tumor chemotherapy, researchers have synthesized many new platinum analogs as anticancer agents that show better cytotoxicity, and less off-target effects with less cellular resistance. This follows the introduction of oxaliplatin, water-soluble carboplatin, multinuclear platinum and newly synthesized complexes, etc. Method: This review emphasizes recent advancements in drug design and development, the mechanism of platinum (II) complexes, their stereochemistry, current updates, and biomedical applications of platinum-based anticancer agents. Conclusion: In the last few decades, the popularity of platinum complexes as potent anti-cancer agents has risen as scientists have synthesized many new platinum complexes that exhibit better cytotoxicity coupled with less off-target effects.


2021 ◽  
Author(s):  
Salim Albukhaty ◽  
Hassan Al-Karagoly ◽  
alireza allafchian ◽  
Seyed Amir Hossein Jalali ◽  
Thair Alkelabi ◽  
...  

Abstract Electrospun polyvinyl alcohol and Tragacanth Gum were used to develop nanofibrous scaffolds containing poorly water-soluble beta-sitosterol. Different Concentration and Ratio of Polymeric composite: (10%) of β-S concentration in (PVA) 8 %, (TG) 0.5%, and 1% respectively were added, prepared and electrospun. The methods have included four parameters (Solution concentration, feeding rate, voltage, and distance of the collector to the tip of the needle) for designing and compared the nanofibers' average diameters. The nanofibers collected were identified via SEM, FTIR, and XRD measurements. A contact angle measurement described the hydrophilicity of the scaffold. MTT test was assessed for obtained nanofibers by using L929 normal fibroblast cells. The %age of mechanical strength, porosity, and deterioration of the scaffolds was well discussed. The average nanofibre ranged from 63 ± 20 nm to 97 ± 46 nm in diameters. The nanofibers loaded with β-S were freely soluble in water and displayed a short release lag time. The dissolution was related to an immediate dissolution, submicron-level recrystallization of β-S with sufficient conditions for nanofibers for L929 cell culture that could be used in biomedical applications. It concluded that electrospinning is a promising technique for poorly water-soluble β-S formulations that could be used in biomedical applications.


Polymers ◽  
2019 ◽  
Vol 11 (2) ◽  
pp. 214 ◽  
Author(s):  
Carla Palomino-Durand ◽  
Marco Lopez ◽  
Frédéric Cazaux ◽  
Bernard Martel ◽  
Nicolas Blanchemain ◽  
...  

Injectable pre-formed physical hydrogels provide many advantages for biomedical applications. Polyelectrolyte complexes (PEC) formed between cationic chitosan (CHT) and anionic polymers of cyclodextrin (PCD) render a hydrogel of great interest. Given the difference between water-soluble (PCDs) and water-insoluble PCD (PCDi) in the extension of polymerization, the present study aims to explore their impact on the formation and properties of CHT/PCD hydrogel obtained from the variable ratios of PCDi and PCDs in the formulation. Hydrogels CHT/PCDi/PCDs at weight ratios of 3:0:3, 3:1.5:1.5, and 3:3:0 were elaborated in a double–syringe system. The chemical composition, microstructure, viscoelastic properties, injectability, and structural integrity of the hydrogels were investigated. The cytotoxicity of the hydrogel was also evaluated by indirect contact with pre-osteoblast cells. Despite having similar shear–thinning and self-healing behaviors, the three hydrogels showed a marked difference in their rheological characteristics, injectability, structural stability, etc., depending on their PCDi and PCDs contents. Among the three, all the best above-mentioned properties, in addition to a high cytocompatibility, were found in the hydrogel 3:1.5:1.5. For the first time, we gained a deeper understanding of the role of the PCDi/PCDs in the injectable pre-formed hydrogels (CHT/PCDi/PCDs), which could be further fine-tuned to enhance their performance in biomedical applications.


2019 ◽  
Vol 48 (28) ◽  
pp. 10385-10392 ◽  
Author(s):  
Xinyue Dou ◽  
Xiaoyu Chen ◽  
Haiguang Zhu ◽  
Yong Liu ◽  
Dongyun Chen ◽  
...  

Recent advances of water-soluble metal nanoclusters (MNCs) in designing highly luminescent MNCs, ligand shell engineering, tracking MNC's growth processes, and biomedical applications are highlighted.


Molecules ◽  
2020 ◽  
Vol 25 (2) ◽  
pp. 421 ◽  
Author(s):  
Daouda Ndiaye ◽  
Sébastien Coufourier ◽  
Mbaye Diagne Mbaye ◽  
Sylvain Gaillard ◽  
Jean-Luc Renaud

The development of efficient and low-cost catalytic systems is important for the replacement of robust noble metal complexes. The synthesis and application of a stable, phosphine-free, water-soluble cyclopentadienone iron tricarbonyl complex in the reduction of polarized double bonds in pure water is reported. In the presence of cationic bifunctional iron complexes, a variety of alcohols and amines were prepared in good yields under mild reaction conditions.


Pharmaceutics ◽  
2019 ◽  
Vol 11 (7) ◽  
pp. 327 ◽  
Author(s):  
Kamil Rahme ◽  
Nazih Dagher

Polyethylene glycol (PEG) is one of the most frequently used polymers for coating nanocarriers to enhance their biocompatibility, hydrophilicity, stability, and biodegradability. PEG is now considered to be among the best biocompatible polymers. It offers sterical hindrance against other nanoparticles and blood components such as opsonin, preventing their macrophage phagocytosis and resulting in a prolonged circulation time in blood stream, consequently a ‘stealth character’ in vivo. Therefore, PEG has a very promising future for the development of current therapeutics and biomedical applications. Moreover, the vast number of molecules that PEG can conjugate with might enhance its ability to have an optimistic perspective for the future. This review will present an update on the chemistry used in the modern conjugation methods for a variety of PEG conjugates, such methods include, but are not limited to, the synthesis of targeting PEG conjugates (i.e., Peptides, Folate, Biotin, Mannose etc.), imaging PEG conjugates (i.e., Coumarin, Near Infrared dyes etc.) and delivery PEG conjugates (i.e., doxorubicin, paclitaxel, and other hydrophobic low molecular weight drugs). Furthermore, the type of nanoparticles carrying those conjugates, along with their biomedical uses, will be briefly discussed.


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