Preparation and Characterization of 2-Hydroxypropyltrimcthyl Ammonium Chloride Chitosan

2011 ◽  
Vol 183-185 ◽  
pp. 2216-2220
Author(s):  
Zheng Jin ◽  
Kai Zhao ◽  
Gang Chen ◽  
Xu Zhang
Keyword(s):  
Ammonium Chloride ◽  
Water Solubility ◽  
Covalent Binding ◽  
Chemical Properties ◽  
Limiting Factor ◽  
Biological Degradation ◽  
Phagocytic Cells ◽  
Enhance Gene Expression ◽  
Primary Amino ◽  
Ph Range

Chitosan has the potential to act as mediators of DNA transfection targeted to phagocytic cells such as macrophages, and to protect against biological degradation by nucleases as well as enhance gene expression. However, the poor solubility of Chitosan is the major limiting factor in its utilization. 2-hydroxypropyltrimcthyl ammonium chloride Chitosan has be prepared successfully through covalent binding of 2,3-Epoxypropyltrimethylammonium chloride ligands to the polymer’s primary amino groups and the polymer’s structure was verified with FT-IR spectra and NMR spectra. The new polymers were obtained with degree of quaternization (DQ) values around 34%, except in the case of the Phe-derived polymer, and thus possess reduced net positive charge as compared to the parent Chitosan. This study provided the new peptide-Chitosans with full water-solubility over practically the entire physiological pH range and led to more disordered. Globally, the new peptide Chitosans and especially the Asp-derived polymer, possess physico-chemical properties that turn them into promising candidates as novel Chitosan-based vaccine delivery systems.

scholarly journals An Overview of Current Knowledge on the Properties, Synthesis and Applications of Quaternary Chitosan Derivatives

Polymers ◽  
2020 ◽  
Vol 12 (12) ◽  
pp. 2878
Author(s):  
Emanuelle Dantas Freitas ◽  
Celso Fidelis Moura Jr. ◽  
Jonas Kerwald ◽  
Marisa Masumi Beppu
Keyword(s):  
Water Solubility ◽  
Current Knowledge ◽  
Hydroxyl Groups ◽  
Phosphonium Salts ◽  
Experimental Conditions ◽  
Quaternized Chitosan ◽  
Wide Ph Range ◽  
Primary Amino ◽  
Ph Range ◽  
Low Solubility

Chitosan, a chitin-derivative polysaccharide, known for its non-toxicity, biocompatibility and biodegradability, presents limited applications due to its low solubility in neutral or basic pH medium. Quaternization stands out as an alternative to modify this natural polymer, aiming to improve its solubility over a wide pH range and, consequently, expand its range of applications. Quaternization occurs by introducing a quaternary ammonium moiety onto or outside the chitosan backbone, via chemical reactions with primary amino and hydroxyl groups, under vast experimental conditions. The oldest and most common forms of quaternized chitosan involve N,N,N-trimethyl chitosan (TMC) and N-[(2-hydroxy-3-trimethyl ammonium) propyl] chitosan (HTCC) and, more recently, quaternized chitosan by insertion of pyridinium or phosphonium salts. By modifying chitosan through the insertion of a quaternary moiety, permanent cationic charges on the polysaccharide backbone are achieved and properties such as water solubility, antimicrobial activity, mucoadhesiveness and permeability are significantly improved, enabling the application mainly in the biomedical and pharmaceutical areas. In this review, the main quaternized chitosan compounds are addressed in terms of their structure, properties, synthesis routes and applications. In addition, other less explored compounds are also presented, involving the main findings and future prospects regarding the field of quaternized chitosans.

The Malachite Green Biodegradation in Bioreactors on Various pH Domains

2019 ◽  
Vol 70 (8) ◽  
pp. 2996-2999
Author(s):  
Viorel Gheorghe ◽  
Catalina Gabriela Gheorghe ◽  
Andreea Bondarev ◽  
Vasile Matei ◽  
Mihaela Bombos
Keyword(s):  
Malachite Green ◽  
Contact Time ◽  
Dominant Species ◽  
Wastewater Treatment Plants ◽  
Organic Substances ◽  
Biological Degradation ◽  
Growth Promoters ◽  
Ph Values ◽  
Biological Sludge ◽  
Ph Range

In the experimental study was studied the malachite green colorant biodegradation in biological sludge with biological activity. The biodegradability tests were carried out in laboratory bioreactors, on aqueous solutions of green malachite contacted with microorganisms in which the dominant species is Paramecium caudatum, in a pH range between 8 and 12, temperatures in the ranges 25-350C, using pH neutralizing substances and biomass growth promoters. The colorant initial concentrations and those obtained after biological degradation depending on the contact time, at certain pH values, were established through UV-Vis spectrometry. The studies have shown the measure of possible biological degradation of some organic substances with extended uses, with largely aromatic structure, resistance to biodegradation of microorganisms, commonly used in wastewater treatment plants.

scholarly journals Competitive Biological Activities of Chitosan and Its Derivatives: Antimicrobial, Antioxidant, Anticancer, and Anti-Inflammatory Activities

2018 ◽  
Vol 2018 ◽  
pp. 1-13 ◽  
Author(s):  
Suyeon Kim
Keyword(s):  
Water Solubility ◽  
Biological Activities ◽  
Biological Properties ◽  
Biomedical Science ◽  
Amino Groups ◽  
Chitosan Oligosaccharides ◽  
Primary Amino ◽  
Anti Inflammatory ◽  
Key Functional Groups ◽  
Application Fields

Chitosan is obtained from alkaline deacetylation of chitin, and acetamide groups are transformed into primary amino groups during the deacetylation. The diverse biological activities of chitosan and its derivatives are extensively studied that allows to widening the application fields in various sectors especially in biomedical science. The biological properties of chitosan are strongly depending on the solubility in water and other solvents. Deacetylation degree (DDA) and molecular weight (MW) are the most decisive parameters on the bioactivities since the primary amino groups are the key functional groups of chitosan where permits to interact with other molecules. Higher DDA and lower MW of chitosan and chitosan derivatives demonstrated higher antimicrobial, antioxidant, and anticancer capacities. Therefore, the chitosan oligosaccharides (COS) with a low polymerization degree are receiving a great attention in medical and pharmaceutical applications as they have higher water solubility and lower viscosity than chitosan. In this review articles, the antimicrobial, antioxidant, anticancer, anti-inflammatory activities of chitosan and its derivatives are highlighted. The influences of physicochemical parameters of chitosan like DDA and MW on bioactivities are also described.

scholarly journals Estimation of the retention behaviour of s-triazine derivatives applying multiple regression analysis of selected molecular descriptors

2013 ◽  
pp. 229-237 ◽  
Author(s):  
Lidija Jevric ◽  
Sanja Podunavac-Kuzmanovic ◽  
Strahinja Kovacevic ◽  
Natasa Kalajdzija ◽  
Bratislav Jovanovic
Keyword(s):  
Dissociation Constant ◽  
Water Solubility ◽  
Molecular Descriptors ◽  
Chemical Properties ◽  
Log P ◽  
Retention Factors ◽  
Solute Retention ◽  
Physico Chemical ◽  
Hydrophilic Lipophilic Balance ◽  
Triazine Derivatives

The estimation of retention factors by correlation equations with physico-chemical properties can be of great helpl in chromatographic studies. The retention factors were experimentally measured by RP-HPTLC on impregnated silica gel with paraffin oil using two-component solvent systems. The relationships between solute retention and modifier concentration were described by Snyder?s linear equation. A quantitative structure-retention relationship was developed for a series of s-triazine compounds by the multiple linear regression (MLR) analysis. The MLR procedure was used to model the relationships between the molecular descriptors and retention of s-triazine derivatives. The physicochemical molecular descriptors were calculated from the optimized structures. The physico-chemical properties were the lipophilicity (log P), connectivity indices (?), total energy (Et), water solubility (log W), dissociation constant (pKa), molar refractivity (MR), and Gibbs energy (GibbsE) of s-triazines. A high agreement between the experimental and predicted retention parameters was obtained when the dissociation constant and the hydrophilic-lipophilic balance were used as the molecular descriptors. The empirical equations may be successfully used for the prediction of the various chromatographic characteristics of substances, with a similar chemical structure.

scholarly journals Influence of hydrotalcite preparation conditions on its physico-chemical properties

2019 ◽  
Vol 12 (1) ◽  
pp. 119-126
Author(s):  
Miroslava Mališová ◽  
Michal Horňáček ◽  
Pavol Hudec ◽  
Jozef Mikulec ◽  
Vladimír Jorík ◽  
...  
Keyword(s):  
Catalytic Properties ◽  
Chemical Properties ◽  
Synthesis Temperature ◽  
Optimal Synthesis ◽  
Preparation Process ◽  
Optimal Conditions ◽  
Temperature Range ◽  
Preparation Conditions ◽  
Physico Chemical ◽  
Ph Range

Abstract The aim of the research was to prepare and characterize hydrotalcite synthesized under different preparation conditions. The most common hydrotalcite preparation is the co-precipiaton method. The preparation process strongly influences the catalytic properties of hydrotalcite; therefore, optimal conditions have to be determined. During the study, seven samples of the catalyst were prepared in the pH range from 8 to 12 and the synthesis temperature range from 25 to 55 °C. Based on several catalyst properties, optimal synthesis pH 10 was found. Ideal temperature of the preparation was determined to be 35 °C, but the temperature does not have a significant effect on the catalyst properties.

scholarly journals Characterization of starch from different non-traditional sources and its application as coating in ‘Palmer’ mango fruit

2020 ◽  
Vol 44 ◽  
Author(s):  
Antonio Augusto Marques Rodrigues ◽  
Luana Ferreira dos Santos ◽  
Rayssa Ribeiro da Costa ◽  
Débora Tamara Félix ◽  
José Henrique Bernardino Nascimento ◽  
...  
Keyword(s):  
Water Solubility ◽  
Amylose Content ◽  
Starch Content ◽  
Chemical Properties ◽  
Seed Kernel ◽  
Mango Fruit ◽  
Mango Seed Kernel ◽  
Randomized Experimental Design ◽  
Mango Seed ◽  
Biodegradable Coatings

ABSTRACT Yam, cassava, jackfruit seed and mango seed kernel have potential for the extraction and use as starch in the food industry of starch or for the formulation of biodegradable coatings. As a biodegradable coating, starch can be applied in fruits characterized by a fast maturation, such as mango, which requires technologies to increase its shelf life. The aim of this study was to characterize starch from four non-traditional sources and to evaluate their potential as coating for ‘Palmer’ mango fruit. Starches used were extracted from cassava, mango seed kernel, jackfruit seed, and yam, and had their physical, optical, and chemical properties characterized for later use as coatings of ‘Palmer’ mango fruit. Fruits were coated with 3% cassava starch, 3.5% jackfruit seed starch, 3.5% mango seed kernel starch and 3.5% yam starch, and were compared to the control (uncoated). They were then stored at 24.4 ± 0.3 °C and 87 ± 2% RH and evaluated for 12 days. A 5x7 factorial arrangement in a completely randomized experimental design was adopted. Total starch content was higher than 70% in the four sources of starch. Starches from jackfruit and yam had higher amylose content. The four sources of starch had low water solubility and swelling power, with jackfruit seed starch having the highest values. The coating sources were effective in maintaining quality, particularly mango seed kernel starch because it reduced respiratory rate and weight loss in 27.7% and 33.8%, respectively, as well as jackfruit seed starch as it delayed fruit skin yellowing.

scholarly journals Production and Characterization of Esterase in Lantinus tigrinus for Degradation of Polystyrene

2013 ◽  
Vol 62 (1) ◽  
pp. 101-108 ◽  
Author(s):  
LUBNA TAHIR ◽  
MUHAMMAD ISHTIAQ ALI ◽  
MUHAMMAD ZIA ◽  
NAIMA ATIQ ◽  
FARIHA HASAN ◽  
...  
Keyword(s):  
Acidic Medium ◽  
Specific Activity ◽  
Mineral Salt Medium ◽  
Tween 80 ◽  
Synthetic Polymers ◽  
Ftir Analysis ◽  
Polystyrene Film ◽  
Biological Degradation ◽  
Ph Range

Polystyrene is considered stable to biological degradation. Lantinus tigrinus isolated from wood sample produced esterase in growth medium under normal conditions. However, acidic medium, 37 degrees C temperature, presence of tween 80; and urea and yeast extract in mineral salt medium enhance the production of esterase and specific activity. Purified esterase was active at broad pH range and 45 degrees C. FTIR analysis confirmed that esterase produced by Lantinus tigrinus effectively degraded polystyrene film and broke macromolecules down to non-toxic molecules. This study concludes that the presence of Lantinus tigrinus at dumping sites can be exploited for waste management containing high molecular weight synthetic polymers.

scholarly journals Extracted Compounds from Neem Leaves as Antimicrobial Agent on the Physico-Chemical Properties of Seaweed-Based Biopolymer Films

Polymers ◽  
2020 ◽  
Vol 12 (5) ◽  
pp. 1119 ◽  
Author(s):  
U. Seeta Uthaya Kumar ◽  
S. N. Abdulmadjid ◽  
N. G. Olaiya ◽  
A. A. Amirul ◽  
S. Rizal ◽  
...  
Keyword(s):  
Gamma Irradiation ◽  
Water Solubility ◽  
Composite Films ◽  
Chemical Properties ◽  
Antimicrobial Activities ◽  
Vapour Permeability ◽  
Control Film ◽  
Biocomposite Films ◽  
Neem Leaves ◽  
The Matrix

Neem leaves extract was incorporated into the matrix of seaweed biopolymer, and the seaweed-neem biocomposite films were irradiated with various doses of gamma irradiation (0.5, 1.5, 2.5, 3.5, and 4.5 kGy). The physical, barrier, antimicrobial, and mechanical properties of the films were studied. The incorporation of 5% w/w neem leaves extract into a seaweed-based film, and gamma irradiation dose of 2.5 kGy was most effective for improved properties of the film. The results showed that the interfacial interaction of the seaweed-neem improved with physical changes in colour and opacity. The water solubility, moisture content, and water vapour permeability and biodegradability rate of the film reduced. The contact angle values increased, which was interpreted as improved hydrophobicity. The tensile strength and modulus of the films increased, while the elongation of the composite films decreased compared to the control film. The film’s antimicrobial activities against bacteria were improved. Thus, neem leaves extract in combination with the application of gamma irradiation enhanced the performance properties of the film that has potential as packaging material.

scholarly journals Lipoatrophy in GH deficient patients treated with a long-acting pegylated GH

2009 ◽  
Vol 161 (4) ◽  
pp. 533-540 ◽  
Author(s):  
Philippe Touraine ◽  
Gwyn A D'Souza ◽  
Ione Kourides ◽  
Roger Abs ◽  
Paul Barclay ◽  
...  
Keyword(s):  
Injection Site ◽  
Covalent Binding ◽  
Limiting Factor ◽  
Double Blind ◽  
Treatment Groups ◽  
Parallel Group ◽  
Adult Gh Deficiency ◽  
Long Acting ◽  
Design And Methods ◽  
Group D

ObjectiveChanges observed during adult GH deficiency (GHD) are most often reversed with the administration of recombinant human GH (rhGH). To avoid daily injections, a long-acting GH molecule has been obtained by covalent binding of polyethylene glycol (PEG) with rhGH (PEG–GH), allowing weekly s.c. injections. This study was designed to assess its efficacy and safety, in adult GHD subjects.Design and methodsThis was a randomized, double-blind, placebo-controlled, multiple-dose, parallel group study. Subjects were recruited from 34 centers. A total of 105 subjects with GHD were assigned a treatment. They received 6 weekly injections of either PEG–GH or placebo. Subjects were randomized into one out of four treatment groups (Groups A–D) or placebo (Group E). Groups A, B, and C received 1, 3, and 4 mg PEG–GH respectively, for the first 3 weeks followed by 2, 6, and 8 mg PEG–GH respectively, for the remaining 3 weeks. Group D received 4 mg PEG–GH for 6 weeks. Group E received placebo. The study was suspended because of the development of lipoatrophy in certain subjects and restarted with an injection rotation plan, before being terminated due to further subjects developing lipoatrophy.ResultsA total of 13 cases of injection-site lipoatrophy were reported, of which ten were in females and three occurred after the first injection; all cases were independent of PEG–GH dose or IGF1 levels, either basal or under treatment.ConclusionThe unpredictable occurrence of injection-site lipoatrophy with weekly long-acting pegylated GH molecules may be a limiting factor for their development.

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