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Mei L, Zhu Z, Wang C, Sun C, Chen P, Cai H, Chen X, Du X. Investigation on chain segment motions of various starch molecules under different glycerol-water system. Int J Biol Macromol 2024; 259:129247. [PMID: 38199530 DOI: 10.1016/j.ijbiomac.2024.129247] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2023] [Revised: 12/03/2023] [Accepted: 01/03/2024] [Indexed: 01/12/2024]
Abstract
The molecular motion of starch at different glycerol concentrations (0, 20, 50, and 80 %) was investigated using Electron Paramagnetic Resonance (EPR) spectroscopy. Fourier-transform infrared (FTIR) spectroscopy and 1H nuclear magnetic resonance (1H NMR) spectroscopy confirmed that hydroxyl groups at the C2 and C3 positions of glucose units in corn starch (CS), waxy corn starch (WCS), and high amylose corn starch (HCS) were labeled with 4-amino-TEMPO. The crystallinities of CS, WCS, and HCS after spin-labeling decreased from 30.68 % to 3.21 %, 39.36 % to 1.65 %, and 28.54 % to 8.08 %, respectively. The pseudoplastic fluid properties of the spin-labeled starch remained shear-thin at different glycerol concentrations. EPR revealed the fast- and slow-motion components of the spin-labeled starch molecules dispersed in water. At a glycerol concentration of 20 %, the slow-motion component disappeared, indicating a faster rotational motion of the starch chain segments. As the glycerol concentration increased to 50 and 80 %, the rotational motion slowed because of high viscosity. In particular, the mobility of the spin-labeled WCS chains increased owing to easier access of glycerol and water to the branched structure. This study directly observed the dynamics of the molecular behavior of starch in glycerol-water systems.
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Affiliation(s)
- Liping Mei
- Anhui Engineering Laboratory for Agro-Products Processing, School of Tea & Food Science and Technology, Anhui Agricultural University, Hefei 230036, Anhui, China
| | - Zhijie Zhu
- Anhui Engineering Laboratory for Agro-Products Processing, School of Tea & Food Science and Technology, Anhui Agricultural University, Hefei 230036, Anhui, China
| | - Caihong Wang
- Anhui Engineering Laboratory for Agro-Products Processing, School of Tea & Food Science and Technology, Anhui Agricultural University, Hefei 230036, Anhui, China
| | - Chengyi Sun
- Anhui Engineering Laboratory for Agro-Products Processing, School of Tea & Food Science and Technology, Anhui Agricultural University, Hefei 230036, Anhui, China
| | - Peirong Chen
- Department of Applied Chemistry, School of Science, Anhui Agricultural University, Hefei, China
| | - Huimei Cai
- State Key Laboratory of Tea Plant Biology and Utilization, School of Tea & Food Science and Technology, Anhui Agricultural University, Hefei 230036, Anhui, China.
| | - Xu Chen
- Anhui Engineering Laboratory for Agro-Products Processing, School of Tea & Food Science and Technology, Anhui Agricultural University, Hefei 230036, Anhui, China.
| | - Xianfeng Du
- Anhui Engineering Laboratory for Agro-Products Processing, School of Tea & Food Science and Technology, Anhui Agricultural University, Hefei 230036, Anhui, China; State Key Laboratory of Tea Plant Biology and Utilization, School of Tea & Food Science and Technology, Anhui Agricultural University, Hefei 230036, Anhui, China.
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2
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Jananishree S, Balakumar S, Mahesh N. Investigation on anti-quorum sensing activities of chitosan AgNP's-chitosanase against MDR pathogens. Microb Pathog 2023:106173. [PMID: 37295482 DOI: 10.1016/j.micpath.2023.106173] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2023] [Revised: 05/07/2023] [Accepted: 05/23/2023] [Indexed: 06/12/2023]
Abstract
Marine bio-nanotechnology is a new promising field having high perspective in the area of biological research. In 2018 the production of crustacean shells especially from shrimp is about 54,500 tons on South East coast of India. The current study focuses on the use of extracted chitosan (Squilla shells) polymer in silver nanoparticle synthesis along with immobilized chitosanase synergistically improves the antimicrobial and quorum quenching effects against the multi drug resistant (MDR) pathogens. The main objective of the study is to synthesize the chitosan AgNPs and to immobilize the enzyme chitosanase with it and to study the anti quorum sensing (quorum quenching) activity against MDR pathogens. This study will render a new ideology to eliminate biofilm formation and suppress the pathogenicity of planktonic MDR pathogens. Since the combinations of chitosanase, as well as chitosan AgNPs, are very efficient in eliminating them.
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Affiliation(s)
- S Jananishree
- Department of Chemistry and Biosciences, School of Chemical and Biotechnology, SASTRA University, Kumbakonam, 612001, Tamilnadu, India; Actinomycetes Bioprospecting Lab Centre for Research in Infectious Diseases (CRID), School of Chemical and Biotechnology, SASTRA University, Tirumalaisamudram, Thanjavur, 613401, Tamilnadu, India.
| | - S Balakumar
- Department of Chemistry and Biosciences, School of Chemical and Biotechnology, SASTRA University, Kumbakonam, 612001, Tamilnadu, India.
| | - N Mahesh
- Department of Chemistry and Biosciences, School of Chemical and Biotechnology, SASTRA University, Kumbakonam, 612001, Tamilnadu, India.
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3
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Zandanel C, Ponchel G, Noiray M, Vauthier C. Nanoparticles facing the gut barrier: Retention or mucosal absorption? Mechanisms and dependency to nanoparticle characteristics. Int J Pharm 2021; 609:121147. [PMID: 34600059 DOI: 10.1016/j.ijpharm.2021.121147] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2021] [Revised: 07/26/2021] [Accepted: 09/25/2021] [Indexed: 11/16/2022]
Abstract
A better knowledge on influence of nanomedicine characteristics on their biological efficacy and safety is expected to accelerate their clinical translation. This work aimed understanding of the oral fate of polymer-based nanomedicines designed with different characteristics. The influence of nanoparticle characteristics (size, zeta potential, molecular architecture surface design) was explored on biological responses evaluating their retention and absorption by rat jejunum using the Ussing chamber experimental model. Thermodynamic aspects of interactions between nanoparticles and model mucins were elucidated by isothermal titration calorimetry. The retention on mucosa varied between nanoparticles from 18.5 to 97.3 % of the initial amount after a simulation considering the entire jejunum length. Different mechanisms were proposed which promoted mucosal association or oppositely precluded any interactions. Strikingly, mucosal retention was profoundly affected by the size and nature of interactions with the mucus which depended on the nature of the coating material, but not on the zeta potential. The nanoparticle absorption simulated along the whole length of the intestine was low (0.01 to almost 3% of the initial amounts). A saturable mechanism including an upper nanoparticle size limit was evidenced but, needs now to be further elucidated. This work showed that the molecular design and formulation of nanoparticles can guide mechanisms by which nanoparticles interact with the mucosa. The data could be useful to formulators to address different oral drug delivery challenges ranging from the simple increase of residence time and proximity to the absorptive epithelium and systemic delivery using the most absorbed nanoparticles.
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Affiliation(s)
- Christelle Zandanel
- Université Paris-Saclay, Institut Galien Paris-Saclay, UMR CNRS 8612, Chatenay Malabry F-92296, France
| | - Gilles Ponchel
- Université Paris-Saclay, Institut Galien Paris-Saclay, UMR CNRS 8612, Chatenay Malabry F-92296, France
| | - Magali Noiray
- Université Paris-Saclay, Institut Galien Paris-Saclay, UMR CNRS 8612, Chatenay Malabry F-92296, France
| | - Christine Vauthier
- Université Paris-Saclay, Institut Galien Paris-Saclay, UMR CNRS 8612, Chatenay Malabry F-92296, France.
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4
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Fucoidan-based nanostructures: A focus on its combination with chitosan and the surface functionalization of metallic nanoparticles for drug delivery. Int J Pharm 2020; 575:118956. [DOI: 10.1016/j.ijpharm.2019.118956] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2019] [Revised: 11/26/2019] [Accepted: 12/11/2019] [Indexed: 12/12/2022]
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5
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Mura S, Fattal E, Nicolas J. From poly(alkyl cyanoacrylate) to squalene as core material for the design of nanomedicines. J Drug Target 2019; 27:470-501. [PMID: 30720372 DOI: 10.1080/1061186x.2019.1579822] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
This review article covers the most important steps of the pioneering work of Patrick Couvreur and tries to shed light on his outstanding career that has been a source of inspiration for many decades. His discovery of biodegradable poly(alkyl cyanoacrylate) (PACA) nanoparticles (NPs) has opened large perspectives in nanomedicine. Indeed, NPs made from various types of alkyl cyanoacrylate monomers have been used in different applications, such as the treatment of intracellular infections or the treatment of multidrug resistant hepatocarcinoma. This latest application led to the Phase III clinical trial of Livatag®, a PACA nanoparticulate formulation of doxorubicin. Despite the success of PACA NPs, the development of a novel type of NP with higher drug loadings and lower burst release was tackled by the discovery of squalene-based nanomedicines where the drug is covalently linked to the lipid derivative and the resulting conjugate is self-assembled into NPs. This pioneering work was accompanied by a wide range of novel applications which mainly dealt with the management of unmet medical needs (e.g. pancreatic cancer, brain ischaemia and spinal cord injury).
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Affiliation(s)
- Simona Mura
- a Institut Galien Paris-Sud, UMR CNRS 8612, Faculté de Pharmacie, Université Paris-Sud, Université Paris-Saclay , Châtenay-Malabry , France
| | - Elias Fattal
- a Institut Galien Paris-Sud, UMR CNRS 8612, Faculté de Pharmacie, Université Paris-Sud, Université Paris-Saclay , Châtenay-Malabry , France
| | - Julien Nicolas
- a Institut Galien Paris-Sud, UMR CNRS 8612, Faculté de Pharmacie, Université Paris-Sud, Université Paris-Saclay , Châtenay-Malabry , France
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6
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Rhodes CJ. Reactive Radicals on Reactive Surfaces: Heterogeneous Processes in Catalysis and Environmental Pollution Control. PROGRESS IN REACTION KINETICS AND MECHANISM 2019. [DOI: 10.3184/007967405779134038] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Many reactions that occur on solid surfaces are mediated by free radicals. A review is presented of both mechanistic and practical investigations in relation to catalysis and environmental applications. The review begins with actual imaging of surface adsorbed reactive radicals using scanning tunnelling microscopy (STM), and then discusses a range of examples, mainly as underpinned by electron spin resonance (ESR) measurements. Included are surface defects and their reactions, studies of the redox behaviour of zeolites, and the use of radicals adsorbed in zeolites as molecular surface probes of diffusion and reactivity within these important materials. Photocatalysis, mainly using TiO2-based materials, is reviewed both from the fundamental perspective and in terms of some practical examples relating to pollution control. Other reactive oxide surfaces are considered, including silica, and the nature of paramagnetic centres that may be induced thereon by a variety of activation procedures. Evidence is presented for the formation of radical species during heterogeneous reactions on metal surfaces. Finally, the role of free radical generation in creating and modifying polymer and nanomolecular systems is discussed, and the health implications of the ability of some solids such as quartz to generate reactive oxygen radicals in contact with biological media.
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7
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Synthesis of chitosan mediated silver nanoparticles (Ag NPs) for potential antimicrobial applications. ACTA ACUST UNITED AC 2018. [DOI: 10.1016/j.flm.2018.04.002] [Citation(s) in RCA: 154] [Impact Index Per Article: 25.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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8
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Coty JB, Eleamen Oliveira E, Vauthier C. Tuning complement activation and pathway through controlled molecular architecture of dextran chains in nanoparticle corona. Int J Pharm 2017; 532:769-778. [DOI: 10.1016/j.ijpharm.2017.04.048] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2017] [Revised: 04/20/2017] [Accepted: 04/21/2017] [Indexed: 10/19/2022]
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9
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Coty JB, Varenne F, Vachon JJ, Vauthier C. Serial multiple crossed immunoelectrophoresis at a microscale: A stamp-sized 2D immunoanalysis of protein C3 activation caused by nanoparticles. Electrophoresis 2016; 37:2401-9. [PMID: 27387591 DOI: 10.1002/elps.201500572] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2015] [Revised: 06/15/2016] [Accepted: 06/22/2016] [Indexed: 11/06/2022]
Abstract
Crossed immunoelectrophoresis (C-IE) is used to detect and quantify specific proteins. An application allowed the evaluation of complement system activation by nanomaterials. The work aimed to improve the C-IE toward a higher throughput and less tedious method. A new concept was implemented to prepare and run agarose gels. The first and the second dimension of electrophoresis were performed on a single gel plate, prepared before the beginning of the analysis. Several samples were migrated simultaneously on the same migration line. Up to 35 analyses were run at once, providing stamp-sized electrophoregrams (2.8 × 3 cm(2) ) maintaining the performance of the original method performed on 5 × 7 cm(2) gel slabs. Robustness and precision of the method were demonstrated through a validation approach using ANOVA. Handling, experimental duration, amount of reagents, and overall cost of one analysis were considerably reduced compared to the original method. With the same equipment, seven times more analyses can be performed in one run. C-IE can be used to analyze many types of proteins. The new experimental modalities were suitable for the application developed in the present work that was to evaluate activation of protein C3 of the complement system triggered by nanomaterials.
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Affiliation(s)
- Jean-Baptiste Coty
- Institut Galien Paris-Sud, CNRS, Univ. Paris-Sud, Université Paris-Saclay, Châtenay-Malabry, France
| | - Fanny Varenne
- Institut Galien Paris-Sud, CNRS, Univ. Paris-Sud, Université Paris-Saclay, Châtenay-Malabry, France
| | - Jean-Jacques Vachon
- Institut Galien Paris-Sud, CNRS, Univ. Paris-Sud, Université Paris-Saclay, Châtenay-Malabry, France
| | - Christine Vauthier
- Institut Galien Paris-Sud, CNRS, Univ. Paris-Sud, Université Paris-Saclay, Châtenay-Malabry, France.
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10
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Han Q, Wang W, Jia X, Qian Y, Li Q, Wang Z, Zhang W, Yang S, Jia Y, Hu Z. Switchable Liposomes: Targeting-Peptide-Functionalized and pH-Triggered Cytoplasmic Delivery. ACS APPLIED MATERIALS & INTERFACES 2016; 8:18658-18663. [PMID: 27391018 DOI: 10.1021/acsami.6b05678] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
One switchable nanodelivery system was constructed. Liposomes were functionalized by a novel dual-recognition peptide STP, which is pH-responsive as well as the affinity ligand of tumor marker VEGFR2 (the angiogenesis marker vascular endothelial growth factor receptor 2). Efficient drug delivery and in vivo therapy could be "turned on" and accelerated only in the conditions of VEGFR2 overexpression and a mild acidic environment. We envisioned that the successful demonstration of this switchable nanocarrier system would open a new avenue on rapid cytoplasmic delivery for specific cancer diagnostics and therapeutics.
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Affiliation(s)
- Qiuju Han
- CAS Center for Excellence in Nanoscience, National Center for Nanoscience and Technology , Beijing 100190, China
| | - Weizhi Wang
- CAS Center for Excellence in Nanoscience, National Center for Nanoscience and Technology , Beijing 100190, China
| | - Xiangqian Jia
- CAS Center for Excellence in Nanoscience, National Center for Nanoscience and Technology , Beijing 100190, China
| | - Yixia Qian
- CAS Center for Excellence in Nanoscience, National Center for Nanoscience and Technology , Beijing 100190, China
| | - Qian Li
- Institute of Chemistry, Chinese Academy of Science , Beijing 100190, China
| | - Zihua Wang
- CAS Center for Excellence in Nanoscience, National Center for Nanoscience and Technology , Beijing 100190, China
| | - Weikai Zhang
- CAS Center for Excellence in Nanoscience, National Center for Nanoscience and Technology , Beijing 100190, China
- Medical College, Henan University of Science and Technology , Luoyang, Henan 471003, China
| | - Shu Yang
- CAS Center for Excellence in Nanoscience, National Center for Nanoscience and Technology , Beijing 100190, China
| | | | - Zhiyuan Hu
- CAS Center for Excellence in Nanoscience, National Center for Nanoscience and Technology , Beijing 100190, China
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11
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Huang Z, Xie X, Mukerabigwi JF, Wang C, Wang S, Xiao W, Huang X, Cao Y. PTX encapsulated by an XG–DOX conjugate for combination therapy against multi-drug resistance. RSC Adv 2016. [DOI: 10.1039/c6ra20437f] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
A new type of targeted dual drug delivery system was designed and possesses outstanding advantages over ordinary systems, proving effective against MDR cancer cells.
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Affiliation(s)
- Zhuli Huang
- Key Laboratory of Pesticide and Chemical Biology (Ministry of Education)
- College of Chemistry
- Central China Normal University
- Wuhan 430079
- P. R. China
| | - Xuan Xie
- Key Laboratory of Pesticide and Chemical Biology (Ministry of Education)
- College of Chemistry
- Central China Normal University
- Wuhan 430079
- P. R. China
| | - Jean Felix Mukerabigwi
- Key Laboratory of Pesticide and Chemical Biology (Ministry of Education)
- College of Chemistry
- Central China Normal University
- Wuhan 430079
- P. R. China
| | - Chang Wang
- Key Laboratory of Pesticide and Chemical Biology (Ministry of Education)
- College of Chemistry
- Central China Normal University
- Wuhan 430079
- P. R. China
| | - Shufang Wang
- Blood Transfusion Department
- The General Hospital of the People’s Liberation Army
- Beijing 100853
- China
| | - Wang Xiao
- Key Laboratory of Pesticide and Chemical Biology (Ministry of Education)
- College of Chemistry
- Central China Normal University
- Wuhan 430079
- P. R. China
| | - Xueying Huang
- Key Laboratory of Pesticide and Chemical Biology (Ministry of Education)
- College of Chemistry
- Central China Normal University
- Wuhan 430079
- P. R. China
| | - Yu Cao
- Key Laboratory of Pesticide and Chemical Biology (Ministry of Education)
- College of Chemistry
- Central China Normal University
- Wuhan 430079
- P. R. China
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12
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Xie X, Luo S, Mukerabigwi JF, Mei J, Zhang Y, Wang S, Xiao W, Huang X, Cao Y. Targeted nanoparticles from xyloglucan–doxorubicin conjugate loaded with doxorubicin against drug resistance. RSC Adv 2016. [DOI: 10.1039/c6ra01779g] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
The novel targeted Xyloglucan–doxorubicin nanoparticle drug delivery systems (DOX nano-DDSs) exhibited improved cellular uptake, increased accumulation in tumor, higher cytotoxicity against drug resistant tumor cells and reduced side effects.
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Affiliation(s)
- Xuan Xie
- Key Laboratory of Pesticide and Chemical Biology (Ministry of Education)
- College of Chemistry
- Central China Normal University
- Wuhan 430079
- P. R. China
| | - Shiying Luo
- Key Laboratory of Pesticide and Chemical Biology (Ministry of Education)
- College of Chemistry
- Central China Normal University
- Wuhan 430079
- P. R. China
| | - Jean Felix Mukerabigwi
- Key Laboratory of Pesticide and Chemical Biology (Ministry of Education)
- College of Chemistry
- Central China Normal University
- Wuhan 430079
- P. R. China
| | - Jian Mei
- Key Laboratory of Pesticide and Chemical Biology (Ministry of Education)
- College of Chemistry
- Central China Normal University
- Wuhan 430079
- P. R. China
| | - Yuannian Zhang
- Key Laboratory of Pesticide and Chemical Biology (Ministry of Education)
- College of Chemistry
- Central China Normal University
- Wuhan 430079
- P. R. China
| | - Shufang Wang
- Blood Transfusion Department
- The General Hospital of the People's Liberation Army
- Beijing 100853
- China
| | - Wang Xiao
- Key Laboratory of Pesticide and Chemical Biology (Ministry of Education)
- College of Chemistry
- Central China Normal University
- Wuhan 430079
- P. R. China
| | - Xueying Huang
- Key Laboratory of Pesticide and Chemical Biology (Ministry of Education)
- College of Chemistry
- Central China Normal University
- Wuhan 430079
- P. R. China
| | - Yu Cao
- Key Laboratory of Pesticide and Chemical Biology (Ministry of Education)
- College of Chemistry
- Central China Normal University
- Wuhan 430079
- P. R. China
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13
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Ionita G, Ariciu AM, Smith DK, Chechik V. Ion exchange in alginate gels--dynamic behaviour revealed by electron paramagnetic resonance. SOFT MATTER 2015; 11:8968-8974. [PMID: 26399427 DOI: 10.1039/c5sm02062j] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
The formation of alginate gel from low molecular weight alginate and very low molecular weight alginate in the presence of divalent cations was investigated using Electron Paramagnetic Resonance (EPR) spectroscopy. The transition from sol to gel in the presence of divalent cations was monitored by the changes in the dynamics of spin labelled alginate. The immobilisation of the spin labelled alginate in the gel reflects the strength of interaction between the cation and alginate chain. Diffusion experiments showed that both the cation and alginate polyanion in the gel fibres can exchange with molecules in solution. In particular, we showed that dissolved alginate polyanions can replace alginates in the gel fibres, which can hence diffuse through the bulk of the gel. This illustrates the surprisingly highly dynamic nature of these gels and opens up the possibility of preparing multicomponent alginate gels via polyanion exchange process.
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Affiliation(s)
- Gabriela Ionita
- Romanian Academy, Institute of Physical Chemistry "Ilie Murgulescu", 202 Splaiul Independentei, Bucharest, 060021, Romania.
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14
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SINGH PN, TIWARY D, SINHA I. Chromium removal from aqueous media by superparamagnetic starch functionalized maghemite nanoparticles. J CHEM SCI 2015. [DOI: 10.1007/s12039-015-0957-0] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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15
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16
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Hommel H. Explaining spin labelling results through a mean field model of cooperative polymer adsorption with excluded volume. Colloids Surf A Physicochem Eng Asp 2012. [DOI: 10.1016/j.colsurfa.2012.02.037] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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17
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Magnetically controlled release of cisplatin from superparamagnetic starch nanoparticles. Carbohydr Polym 2012; 87:300-308. [DOI: 10.1016/j.carbpol.2011.07.053] [Citation(s) in RCA: 82] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2011] [Revised: 06/27/2011] [Accepted: 07/26/2011] [Indexed: 01/01/2023]
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18
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Lira MCB, Santos-Magalhães NS, Nicolas V, Marsaud V, Silva MPC, Ponchel G, Vauthier C. Cytotoxicity and cellular uptake of newly synthesized fucoidan-coated nanoparticles. Eur J Pharm Biopharm 2011; 79:162-70. [PMID: 21349331 DOI: 10.1016/j.ejpb.2011.02.013] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2010] [Revised: 02/07/2011] [Accepted: 02/15/2011] [Indexed: 10/18/2022]
Abstract
The aim was to synthesize and characterize fucoidan-coated poly(isobutylcyanoacrylate) nanoparticles. The nanoparticles were prepared by anionic emulsion polymerization (AEP) and by redox radical emulsion polymerization (RREP) of isobutylcyanoacrylate using fucoidan as a new coating material. The nanoparticles were characterized, and their cytotoxicity was evaluated in vitro on J774 macrophage and NIH-3T3 fibroblast cell lines. Cellular uptake of labeled nanoparticles was investigated by confocal fluorescence microscopy. Results showed that both methods were suitable to prepare stable formulations of fucoidan-coated PIBCA nanoparticles. Stable dispersions of nanoparticles were obtained by AEP with up to 100% fucoidan as coating material. By the RREP method, stable suspensions of nanoparticles were obtained with only up to 25% fucoidan in a blend of polysaccharide composed of dextran and fucoidan. The zeta potential of fucoidan-coated nanoparticles was decreased depending on the percentage of fucoidan. It reached the value of -44 mV for nanoparticles prepared by AEP with 100% of fucoidan. Nanoparticles made by AEP appeared more than four times more cytotoxic (IC(50) below 2 μg/mL) on macrophages J774 than nanoparticles made by RREP (IC(50) above 9 μg/mL). In contrast, no significant difference in cytotoxicity was highlighted by incubation of the nanoparticles with a fibroblast cell line. On fibroblasts, both types of nanoparticles showed similar cytotoxicity. Confocal fluorescence microscopy observations revealed that all types of nanoparticles were taken up by both cell lines. The distribution of the fluorescence in the cells varied greatly with the type of nanoparticles.
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Affiliation(s)
- M C B Lira
- Centro de Ciências Biológicas, Universidade Federal de Pernambuco, Recife, Brazil
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19
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Alhareth K, Vauthier C, Gueutin C, Ponchel G, Moussa F. Doxorubicin loading and in vitro release from poly(alkylcyanoacrylate) nanoparticles produced by redox radical emulsion polymerization. J Appl Polym Sci 2010. [DOI: 10.1002/app.32789] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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20
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Cao Y, Gu Y, Ma H, Bai J, Liu L, Zhao P, He H. Self-assembled nanoparticle drug delivery systems from galactosylated polysaccharide-doxorubicin conjugate loaded doxorubicin. Int J Biol Macromol 2009; 46:245-9. [PMID: 19958788 DOI: 10.1016/j.ijbiomac.2009.11.008] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2009] [Revised: 11/20/2009] [Accepted: 11/23/2009] [Indexed: 11/29/2022]
Abstract
Xyloglucan was grafted with the doxorubicin (DOX) and galactosamine, a terminal moiety that can be used to target polymeric conjugates to liver hepatocytes. The content of the DOX was over 5% (wt) in the conjugate. The polymeric drug assisted to form nanoparticle drug delivery systems (nanoDDSs) with an average size of 142 nm in diameter when combined with an excess amount of deprotonated doxorubicin in an aqueous phase. A loading content of doxorubicin is as high as 23.8% in the nanoDDS. In an in vitro cytotoxicity experiment, the novel nanoDDS has similar cytotoxicity as free DOX against HepG2 cells. In contrast, for the incubation with HeLa cells of the novel nanoDDS, there was no significant cytotoxicity change. In a human tumor xenograft nude mouse model, the novel nanoDDS generated higher therapeutic effect than non-targeted doxorubicin nanoparticles or free doxorubicin. Together, these results suggest that novel nanoDDS, which has improved transfection efficiency and hepatocyte specificity, may be useful for tumor therapy.
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Affiliation(s)
- Yu Cao
- Key Laboratory of Pesticide and Chemical Biology, Ministry of Education, College of Chemistry, Central China Normal University, 152# Luoyu Road, Wuhan, Hubei 430079, PR China.
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21
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Durand A, Marie E. Macromolecular surfactants for miniemulsion polymerization. Adv Colloid Interface Sci 2009; 150:90-105. [PMID: 19660729 DOI: 10.1016/j.cis.2009.07.002] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2009] [Revised: 06/30/2009] [Accepted: 07/01/2009] [Indexed: 11/26/2022]
Abstract
The use of polymeric surfactants as stabilizers in miniemulsion polymerization was reviewed. The structural characteristics of reported polymeric surfactants were detailed and compared. The concept of multi-functional polymeric surfactants was evidenced. The specificities brought by polymeric surfactants in the process of miniemulsion polymerization in comparison to molecular surfactants were analysed for the stability of the initial monomer emulsion, polymerization kinetics and characteristics of the obtained latexes. The contribution of polymeric surfactants to the control of the characteristics of the obtained nanoparticles was detailed with regard to the nature of the core material and to the surface coverage. Polymeric surfactants can be seen as powerful tools for the design of original nanoparticles. On the basis of the available data, possible research topics are suggested.
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22
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Schwall CT, Banerjee IA. Micro- and Nanoscale Hydrogel Systems for Drug Delivery and Tissue Engineering. MATERIALS 2009. [PMCID: PMC5445705 DOI: 10.3390/ma2020577] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
The pursuit for targeted drug delivery systems has led to the development of highly improved biomaterials with enhanced biocompatibility and biodegradability properties. Micro- and nanoscale components of hydrogels prepared from both natural and artificial components have been gaining significant importance due to their potential uses in cell based therapies, tissue engineering, liquid micro-lenses, cancer therapy, and drug delivery. In this review some of the recent methodologies used in the preparation of a number of synthetic hydrogels such as poly(N-isopropylacrylamide) (pNIPAm), poly(ethylene glycol) (PEG), poly(ethylene oxide) (PEO), polyvinyl alcohol methylacrylate co-polymers (PVA-MA) and polylactic acid (PLA), as well as some of the natural hydrogels and their applications have been discussed in detail.
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Affiliation(s)
| | - Ipsita A. Banerjee
- Author to whom correspondence should be addressed; E-Mail: ; Tel. +1-718-817-4445; Fax: +1-718-817-4432
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23
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Henricus MM, Fath KR, Menzenski MZ, Banerjee IA. Morphology Controlled Growth of Chitosan-Bound Microtubes and a Study of their Biocompatibility and Antibacterial Activity. Macromol Biosci 2009; 9:317-25. [DOI: 10.1002/mabi.200800220] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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24
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Fattal E, Barratt G. Nanotechnologies and controlled release systems for the delivery of antisense oligonucleotides and small interfering RNA. Br J Pharmacol 2009; 157:179-94. [PMID: 19366348 DOI: 10.1111/j.1476-5381.2009.00148.x] [Citation(s) in RCA: 78] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Antisense oligonucleotides and small interfering RNA have enormous potential for the treatment of a number of diseases, including cancer. However, several impediments to their widespread use as drugs still have to be overcome: in particular their lack of stability in physiological fluids and their poor penetration into cells. Association with or encapsulation within nano- and microsized drug delivery systems could help to solve these problems. In this review, we describe the progress that has been made using delivery systems composed of natural or synthetic polymers in the form of complexes, nanoparticles or microparticles.
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Affiliation(s)
- Elias Fattal
- Univ Paris Sud 11, UMR 8612, Châtenay-Malabry, F-92290, France
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25
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Configuration of bovine serum albumin adsorbed on polymer particles with grafted dextran corona. Colloids Surf B Biointerfaces 2009; 69:207-15. [DOI: 10.1016/j.colsurfb.2008.11.017] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2008] [Accepted: 11/17/2008] [Indexed: 11/19/2022]
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26
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Vauthier C, Bouchemal K. Methods for the preparation and manufacture of polymeric nanoparticles. Pharm Res 2008; 26:1025-58. [PMID: 19107579 DOI: 10.1007/s11095-008-9800-3] [Citation(s) in RCA: 476] [Impact Index Per Article: 29.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2008] [Accepted: 12/01/2008] [Indexed: 10/21/2022]
Abstract
This review summarizes the different methods of preparation of polymer nanoparticles including nanospheres and nanocapsules. The first part summarizes the basic principle of each method of nanoparticle preparation. It presents the most recent innovations and progresses obtained over the last decade and which were not included in previous reviews on the subject. Strategies for the obtaining of nanoparticles with controlled in vivo fate are described in the second part of the review. A paragraph summarizing scaling up of nanoparticle production and presenting corresponding pilot set-up is considered in the third part of the review. Treatments of nanoparticles, applied after the synthesis, are described in the next part including purification, sterilization, lyophilization and concentration. Finally, methods to obtain labelled nanoparticles for in vitro and in vivo investigations are described in the last part of this review.
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Affiliation(s)
- Christine Vauthier
- CNRS UMR 8612, Université Paris Sud-11, 92296, Chatenay-Malabry, France.
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27
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Nicolas J, Couvreur P. Synthesis of poly(alkyl cyanoacrylate)‐based colloidal nanomedicines. WILEY INTERDISCIPLINARY REVIEWS-NANOMEDICINE AND NANOBIOTECHNOLOGY 2008; 1:111-127. [DOI: 10.1002/wnan.15] [Citation(s) in RCA: 84] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Julien Nicolas
- Laboratoire de Physico‐Chimie, Pharmacotechnie et Biopharmacie, UMR CNRS 8612, Univ Paris‐Sud, 92296 Châtenay Malabry, France
| | - Patrick Couvreur
- Laboratoire de Physico‐Chimie, Pharmacotechnie et Biopharmacie, UMR CNRS 8612, Univ Paris‐Sud, 92296 Châtenay Malabry, France
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28
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Richard A, Barras A, Younes AB, Monfilliette-Dupont N, Melnyk P. Minimal Chemical Modification of Reductive End of Dextran to Produce an Amphiphilic Polysaccharide Able to Incorporate onto Lipid Nanocapsules. Bioconjug Chem 2008; 19:1491-5. [DOI: 10.1021/bc700444t] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Affiliation(s)
- Antoine Richard
- Laboratoire de Chimie et MicroNanotechnologie à Visée Thérapeutique, UMR 8161 CNRS-Université de Lille 2-Université de Lille 1-Institut Pasteur de Lille, and INSERM IFR 142 Institut Pasteur de Lille-Institut de Biologie de Lille, Institut de Biologie de Lille, 1 Rue du Pr. Calmette, 59021 Lille cedex, France
| | - Alexandre Barras
- Laboratoire de Chimie et MicroNanotechnologie à Visée Thérapeutique, UMR 8161 CNRS-Université de Lille 2-Université de Lille 1-Institut Pasteur de Lille, and INSERM IFR 142 Institut Pasteur de Lille-Institut de Biologie de Lille, Institut de Biologie de Lille, 1 Rue du Pr. Calmette, 59021 Lille cedex, France
| | - Amena Ben Younes
- Laboratoire de Chimie et MicroNanotechnologie à Visée Thérapeutique, UMR 8161 CNRS-Université de Lille 2-Université de Lille 1-Institut Pasteur de Lille, and INSERM IFR 142 Institut Pasteur de Lille-Institut de Biologie de Lille, Institut de Biologie de Lille, 1 Rue du Pr. Calmette, 59021 Lille cedex, France
| | - Nicole Monfilliette-Dupont
- Laboratoire de Chimie et MicroNanotechnologie à Visée Thérapeutique, UMR 8161 CNRS-Université de Lille 2-Université de Lille 1-Institut Pasteur de Lille, and INSERM IFR 142 Institut Pasteur de Lille-Institut de Biologie de Lille, Institut de Biologie de Lille, 1 Rue du Pr. Calmette, 59021 Lille cedex, France
| | - Patricia Melnyk
- Laboratoire de Chimie et MicroNanotechnologie à Visée Thérapeutique, UMR 8161 CNRS-Université de Lille 2-Université de Lille 1-Institut Pasteur de Lille, and INSERM IFR 142 Institut Pasteur de Lille-Institut de Biologie de Lille, Institut de Biologie de Lille, 1 Rue du Pr. Calmette, 59021 Lille cedex, France
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29
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Vauthier C, Labarre D, Ponchel G. Design aspects of poly(alkylcyanoacrylate) nanoparticles for drug delivery. J Drug Target 2008; 15:641-63. [PMID: 18041633 DOI: 10.1080/10611860701603372] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
Poly(alkylcyanoacrylate) (PACA) nanoparticles were first developed 25 years ago taking advantage of the in vivo degradation potential of the polymer and of its good acceptance by living tissues. Since then, various PACA nanoparticles were designed including nanospheres, oil-containing and water-containing nanocapsules. This made possible the in vivo delivery of many types of drugs including those presenting serious challenging delivery problems. PACA nanoparticles were proven to improve treatments of severe diseases like cancer, infections and metabolic disease. For instance, they can transport drugs across barriers allowing delivery of therapeutic doses in difficult tissues to reach including in the brain or in multidrug resistant cells. This review gives an update on the more recent developments and achievements on design aspects of PACA nanoparticles as delivery systems for various drugs to be administered in vivo by different routes of administration.
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30
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de Moura MR, Aouada FA, Mattoso LHC. Preparation of chitosan nanoparticles using methacrylic acid. J Colloid Interface Sci 2008; 321:477-83. [PMID: 18295778 DOI: 10.1016/j.jcis.2008.02.006] [Citation(s) in RCA: 68] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2007] [Revised: 01/15/2008] [Accepted: 02/06/2008] [Indexed: 10/22/2022]
Abstract
In this work the preparation of chitosan nanoparticle was investigated using methacrylic acid in different conditions and studied by particle size analyzer, zeta-potential, Fourier transform infrared spectroscopy (FT-IR), nuclear magnetic resonance (NMR) and transmission electron microscopy (TEM). The particle size was dependent on the chitosan concentration used during the preparation method. Nanoparticles with sizes as small as 60 nm were achieved, that can be extremely important for several applications. The nanoparticles solution was also pH-sensitive, due to swelling and aggregation of the nanoparticles. The nanoparticles obtained presented a very homogeneous morphology showing a quite uniform particles size distribution and a rather spherical shape.
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Affiliation(s)
- Márcia R de Moura
- Departamento de Química da UFSCar, 13560-905, São Carlos, SP, Brazil
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31
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Noncovalently modified carbon nanotubes with carboxymethylated chitosan: a controllable donor-acceptor nanohybrid. Int J Mol Sci 2008; 9:120-130. [PMID: 19325737 PMCID: PMC2635665 DOI: 10.3390/ijms9020120] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2008] [Accepted: 01/31/2008] [Indexed: 11/18/2022] Open
Abstract
We report here the modification of multiwalled carbon nanotubes (MWNTs) with a kind of polysaccharide, carboxymethylated chitosan (cmCs), and their potential usage as donor-acceptor nanohybrids. The modified composites (cmCs/MWNTs) were characterized by high-resolution TEM, FT-IR, TGA and time-resolved spectroscopy. The time-resolved spectroscopic experiments revealed that interfacial electron transfer readily takes place between MWNTs and surface immobilized cmCs chains. The forward electron transfer is fast (< 20 ns) while the backward recombination is slow. The recombination process strongly depends on the chain length of carboxylmethylated chitosan, i.e. a shorter recombination lifetime (~1.1 μs) for the shorter-chain cmCs coated MWNTs against that of the longer-chain cmCs coated MWNTs (~3.5 μs). The results demonstrated that the cmCs/MWNTs composite may be applied as a controllable donor-acceptor nanohybrid.
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32
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Chauvierre C, Leclerc L, Labarre D, Appel M, Marden MC, Couvreur P, Vauthier C. Enhancing the tolerance of poly(isobutylcyanoacrylate) nanoparticles with a modular surface design. Int J Pharm 2007; 338:327-32. [PMID: 17324536 DOI: 10.1016/j.ijpharm.2007.01.034] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2006] [Revised: 01/10/2007] [Accepted: 01/13/2007] [Indexed: 10/23/2022]
Abstract
Polymer nanoparticles are designed as nanovehicles to carry drugs in the body in a controlled manner increasing the concentration of the biologically active substance in the diseased organs and cells. The safety and biocompatibility of these nanosystems are those of the many properties that nanoparticles must meet to be used in vivo. Here we show that the cytotoxicity profile of poly(isobutylcyanoacrylate) (PIBCA) nanoparticles is affected by the way the nanosystems were produced and by the design of their surface. It was found that the tolerance of PIBCA nanoparticles by cells could be improved up to 100-fold by coating their surface with polysaccharides and haemoglobin.
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Affiliation(s)
- Cédric Chauvierre
- INSERM U779, Hôpital de Bicêtre, Secteur Broca, 78 rue du Général Leclerc, 94275 Le Kremlin-Bicêtre, France
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33
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Mange S, Dever C, De Bruyn H, Gaborieau M, Castignolles P, Gilbert RG. Grafting of Oligosaccharides onto Synthetic Polymer Colloids. Biomacromolecules 2007; 8:1816-23. [PMID: 17497920 DOI: 10.1021/bm061119o] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
A new method to form colloidally stable oligosaccharide-grafted synthetic polymer particles has been developed. The oligosaccharides, of weight-average degree of polymerization approximately 38, were obtained by enzymatic debranching of amylopectin. Through the use of a cerium(IV)-based redox initiation process, oligosaccharide chains are grafted onto a synthetic polymer colloid comprising electrostatically stabilized poly(methyl methacrylate) or polystyrene latex particles swollen with methyl methacrylate monomer. Ce(IV) creates a radical species on these oligosaccharides, which then propagates, initially with aqueous-phase monomer, then with the methyl methacrylate monomer inside the particles. Ultracentrifugation, NMR, and total starch analyses together prove that the grafting process has occurred, with at least 7.7 wt % starch grafted and a grafting efficiency of 33%. The surfactant used in latex preparation was removed by dialysis, resulting in particles colloidally stabilized with only linear starch as a steric stabilizer. The debranched starch that comprises these oligosaccharides is found to be a remarkably effective colloidal stabilizer, albeit at low electrolyte concentration, stabilizing particles with very sparse surface coverage.
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Affiliation(s)
- Siyabonga Mange
- Key Centre for Polymer Colloids, School of Chemistry F11, The University of Sydney, New South Wales 2006, Australia
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34
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Cheng L, Xiao-Yu K, Xiao-Ming T, Xiong Y. Theoretical investigation of electron paramagnetic resonance spectra and local structure distortion for Mn2+ ions in CaCO3:Mn2+ system: a simple model for Mn2+ ions in a trigonal ligand field. J Phys Chem A 2007; 111:2783-9. [PMID: 17388334 DOI: 10.1021/jp067161v] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
This paper reports on a novel application of a ligand field model for the detection of the local molecular structure of a coordination complex. By diagonalizing the complete energy matrices of the electron-electron repulsion, the ligand field and the spin-orbit coupling for the d5 configuration ion in a trigonal ligand field, the local distortion structure of the (MnO6)10- coordination complex for Mn2+ ions doped into CaCO3, have been investigated. Both the second-order zero-field splitting parameter b(0)2 and the fourth-order zero-field splitting parameter b(0)4 are taken simultaneously in the structural investigation. From the electron paramagnetic resonance (EPR) calculations, the local structure distortion, DeltaR=-0.169 A to -0.156 A, Deltatheta=0.996 degrees to 1.035 degrees for Mn2+ ions in calcite single crystal, DeltaR=-0.185 A to -0.171 A, Deltatheta=3.139 degrees to 3.184 degrees for Mn2+ ions in travertines, and DeltaR=-0.149 A to -0.102 A, Deltatheta=0.791 degrees to 3.927 degrees for Mn2+ ions in shells are determined, respectively. These results elucidate a microscopic origin of various ligand field parameters which are usually used empirically for the interpretation of EPR and optical absorption experiments. It is found that the theoretical results of the EPR and optical absorption spectra for Mn2+ ions in CaCO3 are in good agreement with the experimental findings. Moreover, to understand the detailed physical and chemical properties of the doped CaCO3, the theoretical values of the fourth-order zero-field splitting parameters b(0)4 for Mn2+ ions in travertines and shells are reported first.
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Affiliation(s)
- Lu Cheng
- Institute of Atomic and Molecular Physics, Sichuan University, Chengdu 610065, China, and International Centre for Materials Physics, Academia Sinica, Shenyang 110016, China
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35
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Harth E, Croce TA. Carving Out Niches for Nanostructures: Implementation and Interplay of Building Blocks, Methods, and Tools. Aust J Chem 2006. [DOI: 10.1071/ch06245] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
The number and diversity of techniques to create well-defined polymeric architectures has set the foundation to reinvent macromolecular chemistry’s tenor. This development offers the chance to build refined structures with multifaceted, cross-disciplinary applications. We discuss a few advances in the design and development of selected nanoobjects with far-reaching potential. Herein, well-defined building blocks and introduced methods to establish three-dimensional architectures will be presented. Sequential attachment strategies and tools taken from biological chemistries achieve new levels of specificity.
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