Synthesis and Fungicidal Activity of New <i>N</i>,<i>O</i>-Acyl Chitosan Derivatives

Badawy, Mohamed E. I.; Rabea, Entsar I.; Rogge, Tina; Stevens, Christian V.; Smagghe, Guy; Steurbaut, Walter; Höfte, Monica

doi:10.1021/bm0344295

Cited by 157 publications

(93 citation statements)

References 42 publications

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“…Porém, quando ocorre uma reação de regiosseletividade, com ataque no substituinte ligado ao carbono 6, a reação é chamada de Oacilação, podendo ser empregado, neste caso, como material de partida tanto a quitina como a quitosana 7 .…”

Section: Introductionunclassified

O emprego de quitosana quimicamente modificada com anidrido succínico na adsorção de azul de metileno

Lima¹,

Ribeiro²,

Airoldi³

2006

Quím. Nova

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Recebido em 13/4/05; aceito em 29/8/05; publicado na web em 8/2/06 THE USE OF CHEMICALLY MODIFIED CHITOSAN WITH SUCCINIC ANHYDRIDE IN THE METHYLENE BLUE ADSORPTION. The adsorption capacity of α-chitosan and its modified form with succinic anhydride was compared with the traditional adsorbent active carbon by using the dye methylene blue, employed in the textile industry. The isotherms for both biopolymers were classified as SSA systems in the Giles model, more specifically in L class and subgroup 3. The dye concentration in the supernatant in the adsorption assay was determined through electronic spectroscopy. By calorimetric titration thermodynamic data of the interaction between methyene blue and the chemically modified chitosan at the solid/liquid interface were obtained. The enthalpy of the dye/chitosan interaction gave 2.47 ± 0.02 kJ mol -1 with an equilibrium constant of 7350 ± 10 and for the carbon/dye interaction this constant gave 5951 ± 8. The spontaneity of these adsorptions are reflected by the free Gibbs energies of -22.1 ± 0.4 and -21.5 ± 0.2 kJ mol -1 , respectively, found for these systems. This new adsorbent derived from a natural polysaccharide is as efficient as activated carbon. However 97% of the bonded dye can be eluted by sodium chloride solution, while this same operation elutes only 42% from carbon. Chitosan is efficient in dye removal with the additional advantage of being cheap, non-toxic, biocompatible and biodegradable.Keywords: chitosan; succinic anhydride; methylene blue. INTRODUÇÃOOs polissacarídeos denominados β(1→4)2-acetamida-2-desoxi-D-glicopiranose e β(1→4)2-amino-2-desoxi-D-glicopiranose são conhecidos pelas denominações quitina e quitosana, respectivamente. São biopolímeros interligados por ligações β-glicosídicas, sendo que em ambos os tipos de estruturas não há predominância de quaisquer espécies monoméricas. Assim, ambas as formas coexistem na natureza em uma estrutura polimérica, com grau parcial de desacetilação 1 , constituindo um copolímero. A quitina nativa possui em torno de 10% de grupos aminos livres 2 , enquanto que a forma desacetilada apresenta, em média, um teor desses grupos 1,2 não superior a 97%.Quanto à natureza estrutural desses materiais, tem-se conhecimento de que a quitina pode se apresentar sob as formas α, β e γ. Entretanto, a última é ainda pouco estudada, provavelmente por conter percentuais predominantes das formas α e β na sua constituição. Tanto a quitina natural como a quitosana apresentam alto grau de associação com proteínas, formando as glicoproteínas, com percentual que varia de 20 a 50% nos artrópodes 3 . A quitina faz parte da constituição da estrutura material e protetora dos insetos, animais marinhos e microrganismos celulares. Em processo laboratorial, a quitina é obtida a partir da abertura de anel do grupo exazolina de um derivado de açúcar ou por biossíntese, a partir da glicose em processo enzimático 3 . Um grande número de modificações químicas através de rotas homogênea e heterogênea pode ser realizado no anel glicopiranosídeo d...

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Section: Introductionunclassified

O emprego de quitosana quimicamente modificada com anidrido succínico na adsorção de azul de metileno

Lima¹,

Ribeiro²,

Airoldi³

2006

Quím. Nova

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“…Hemostasis material, medical dressing, hydrogel, drug delivery carrier, gene transfer [22] Biocompatibility, antimicrobial, innocuous, easily degradable, adsorbability, film formation [23][24][25][26][27] Poor spinnability, poor strength, low water-solubility [23,25] Starch Hemostasis material, tissue-engineered scaffold, drug delivery carrier, bone repair material [28,29] Extensive sources, low price, degradation products safe and non-toxic, non-antigenic [28,30] Poor mechanical properties, resistance to water, poor blocking performance [28,30] Alginate Pharmaceutical excipient, pepcid complete, medical dressing [31][32][33][34][35] Hypotoxicity, biocompatibility, suppresses tumor growth, enhances immunity [31][32][33][34][35] Bad biodegradability, cell attachment poor [31][32][33][34][35] Cellulose Pharmaceutical adjuvant [28] Extensive sources, low price [28] Rare adverse reactions [28] Drug-delivery carrier, tissue engineering material [36][37][38] Biodegradable, safe, non-toxic, good physical and chemical properties [37,39] High crystallinity, bad thermal stability [37,39] Chemosynthes material (Copolymer)…”

Section: Chitosanmentioning

confidence: 99%

“…However, the performance of derivatives is often better than chitosan [53]. There are many studies on chitosan derivatives obtained through such processes as acylation, alkylation, sulfation, hydroxylation, quaternization, and carboxymethylation [23][24][25][26][27]. Among them, products obtained through quaternization and carboxymethylation have received increasing amounts of attention because of their good water solubility.…”

Section: Natural Polymer-based Nanomaterialsmentioning

confidence: 99%

Polymer-Based Nanomaterials and Applications for Vaccines and Drugs

et al. 2018

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Nanotechnology plays a significant role in drug development. As carriers, polymeric nanoparticles can deliver vaccine antigens, proteins, and drugs to the desired site of action. Polymeric nanoparticles with lower cytotoxicity can protect the delivered antigens or drugs from degradation under unfavorable conditions via a mucosal administration route; further, the uptake of nanoparticles by antigen-presenting cells can increase and induce potent immune responses. Additionally, nanomaterials are widely used in vaccine delivery systems because nanomaterials can make the vaccine antigen long-acting. This review focuses on some biodegradable polymer materials such as natural polymeric nanomaterials, chemically synthesized polymer materials, and biosynthesized polymeric materials, and points out the advantages and the direction of research on degradable polymeric materials. The application and future perspectives of polymeric materials as delivery carriers and vaccine adjuvants in the field of drugs and vaccines are presented. With the increase of knowledge and fundamental understandings of polymer-based nanomaterials, means of integrating some other attractive properties, such as slow release, target delivery, and alternative administration methods and delivery pathways are feasible. Polymer-based nanomaterials have great potential for the development of novel vaccines and drug systems for certain needs, including single-dose and needle-free deliveries of vaccine antigens and drugs in the future.

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“…Chitosan is a linear polysaccharide composed of β-(1-4)-linked D-glucosamine (deacetylated unit) and Nacetyl-D-glucosamine (acetylated unit). It has been extensively used in medical and pharmaceutical areas due to its abundance, non-toxicity, biocompatibility and biodegradability (Badawy et al, 2004;Sinha et al, 2004).…”

Section: Introductionmentioning

confidence: 99%

Development of Superparamagnetic Iron Oxide Nanoparticles (SPIOs)-Embedded Chitosan Microspheres for Magnetic Resonance (MR)-Traceable Embolotherapy

Kang¹,

Oh²,

Choi³

et al. 2009

Biomolecules and Therapeutics

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-Superparamagnetic iron oxide nanoparticles (SPIOs)-embedded chitosan microspheres were developed for magnetic resonance (MR)-traceable embolotherapy. SPIOs-loaded chitosan microspheres were prepared by emulsion and cross-linking technique and 100-200 μm sized spherical microsparticles were obtained. Loading efficacy and loading amount of SPIOs in microspheres were about 40% and 0.26-0.32%, respectively, when measured by inductively coupled plasma atomic emission spectroscopy. Within 30 days, about 60% of the incorporated SPIOs were released from low cross-linked microspheres, whereas only about 40% of SPIOs was released from highly cross-linked microspheres. Highly cross-linked microspheres were more efficient for lower degree of swelling leading to secure entrapment of SPIOs in matrix. Prepared novel embolic microspheres are expected to be practically applicable for traceable embolotherapy with high resolution and sensitivity through magnetic resonance imaging (MRI).

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Synthesis and Fungicidal Activity of New N,O-Acyl Chitosan Derivatives

Cited by 157 publications

References 42 publications

O emprego de quitosana quimicamente modificada com anidrido succínico na adsorção de azul de metileno

O emprego de quitosana quimicamente modificada com anidrido succínico na adsorção de azul de metileno

Polymer-Based Nanomaterials and Applications for Vaccines and Drugs

Development of Superparamagnetic Iron Oxide Nanoparticles (SPIOs)-Embedded Chitosan Microspheres for Magnetic Resonance (MR)-Traceable Embolotherapy

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