A Novel Preparation of Nanocapsules from Alginate-Oligochitosan

2007 ◽  
Vol 7 (12) ◽  
pp. 4571-4574 ◽  
Author(s):  
Ting Wang ◽  
Zhangqi Feng ◽  
Nongyue He ◽  
Zhifei Wang ◽  
Song Li ◽  
...  
Keyword(s):  
Aqueous Solution ◽  
Molecular Weight ◽  
Efficient Method ◽  
Low Molecular Weight ◽  
Optimal Conditions ◽  
Emulsion System ◽  
Micro Emulsion ◽  
Triton X

A novel, simple and efficient method to prepare a new kind of nanocapsules in a demulsifying W/O micro-emulsion system from low molecular weight (MW) alginate and oligochitosan (OCS) was reported. Low MW alginate (LMWALG) was prepared by radiation of UV in the presence of cathode ion, OCS were used as anode ions. The composition for LMWALG demulsifying W/O micro-emulsion system is 50.75% (wt) of cyclohexane, 17.67% (Triton X-100 + n-pentanol), and 31.58% of LMWALG gelatum, while that for OCS one is 48.21% of cyclohexane, 16.09% (Triton X-100 + n-pentanol), and 35.70% OCS aqueous solution. The preparation of nanocapsules was optimized based on the above compositions for the MW of alginate, the MW of OCS, concentration of OCS and the encapsulation time. Ultimately the MW of LMWALG is 0.13 million and that of OCS is 3000 with a concentration of 1%, encapsulating for 30 min, under the above optimal conditions nanocapsules were formed in diameter of 136 nm.

scholarly journals Low Molecular Weight Gelators Based on Functionalized l-Dopa Promote Organogels Formation

Gels ◽  
2019 ◽  
Vol 5 (2) ◽  
pp. 27 ◽  
Author(s):  
Demetra Giuri ◽  
Nicola Zanna ◽  
Claudia Tomasini
Keyword(s):  
Aqueous Solution ◽  
Molecular Weight ◽  
Rheological Properties ◽  
Rhodamine B ◽  
Lauric Acid ◽  
Water Solution ◽  
Preliminary Test ◽  
Low Molecular Weight ◽  
Coupling Reactions ◽  
Low Molecular Weight Gelators

We prepared the small pseudopeptide Lau-l-Dopa(OBn)2-d-Oxd-OBn (Lau = lauric acid; l-Dopa = l-3,4-dihydroxyphenylalanine; d-Oxd = (4R,5S)-4-methyl-5-carboxyl-oxazolidin-2-one; Bn = benzyl) through a number of coupling reactions between lauric acid, protected l-Dopa and d-Oxd with an excellent overall yield. The ability of the product to form supramolecular organogels has been tested with different organic solvents of increasing polarity and compared with the results obtained with the small pseudopeptide Fmoc-l-Dopa(OBn)2-d-Oxd-OBn. The mechanical and rheological properties of the organogels demonstrated solvent-dependent properties, with a storage modulus of 82 kPa for the ethanol organogel. Finally, to have a preliminary test of the organogels’ ability to adsorb pollutants, we treated a sample of the ethanol organogel with an aqueous solution of Rhodamine B (RhB) for 24 h. The water solution slowly lost its pink color, which became trapped in the organogel.

Stress protein content of mature Brassica seeds and their germination performance

1998 ◽  
Vol 8 (3) ◽  
pp. 347-355 ◽  
Author(s):  
Mary Bettey ◽  
W. E. Finch-Savage
Keyword(s):  
Molecular Weight ◽  
Water Stress ◽  
Seed Development ◽  
Positive Relationship ◽  
Stress Proteins ◽  
Stress Protein ◽  
Low Molecular Weight ◽  
Optimal Conditions ◽  
Seed Vigour ◽  
The Relationship

AbstractPlants respond to sub-optimal conditions by the synthesis of specific ‘stress’ proteins, and these are thought to play a role in stress tolerance. Some of these proteins accumulate during late seed development, arguably to protect against damage during post-maturation drying and subsequent imbibition, prior to germination. Seed vigour is also determined during this late stage of seed development. High vigour seeds are those that can withstand the desiccation required for storage and successfully germinate under sub-optimal conditions to establish healthy seedlings. If stress proteins are involved in tolerating stress conditions, then they are likely to be important determinants of seed vigour. In this work the relationship between seed vigour (measured by seed germination performance following rapid aging, or under water stress) in Brassica oleracea var. capitata and the content of two classes of stress protein (dehydrins and a low molecular weight heat shock protein HSP17.6) at maturity was examined. Dehydrins did not show a positive relationship with seed performance. However, the protein HSP17.6 showed a positive correlation with seed performance, and a treatment that reduced the amount of this protein in the seed also caused a reduction in subsequent seed performance.

Dynamical studies on low molecular weight polyacrylamide aqueous solution

Polymer ◽  
1985 ◽  
Vol 26 (3) ◽  
pp. 397-405 ◽  
Author(s):  
Michel Duval ◽  
Jeanne François ◽  
Dominique Sarazin
Keyword(s):  
Aqueous Solution ◽  
Molecular Weight ◽  
Low Molecular Weight

Weak alkali and alkaline earth metal complexes of low molecular weight ligands in aqueous solution

2008 ◽  
Vol 252 (10-11) ◽  
pp. 1093-1107 ◽  
Author(s):  
Pier G. Daniele ◽  
Claudia Foti ◽  
Antonio Gianguzza ◽  
Enrico Prenesti ◽  
Silvio Sammartano
Keyword(s):  
Aqueous Solution ◽  
Molecular Weight ◽  
Metal Complexes ◽  
Alkaline Earth ◽  
Earth Metal ◽  
Alkaline Earth Metal ◽  
Low Molecular Weight

PROTEOGLYCANS AND SULFATED PROTEINS OF PLATELETS: CHARACTERIZATION AND RESPONSE TO THROMBIN AND ADP

1987 ◽  
Author(s):  
B P Schick ◽  
C J Walsh ◽  
T Jenkins-West
Keyword(s):  
Molecular Weight ◽  
Guinea Pig ◽  
Platelet Activation ◽  
Negative Charge ◽  
Total Cell ◽  
Low Molecular Weight ◽  
Sds Page ◽  
Form Part ◽  
Triton X

The proteoglycans (PG) and sulfated proteins of guinea pig platelets were labeled in vivo by intraperitoneal injection of (35S)sulfate. At 3 days after injection, platelets contained 3 distinct populations of chondroitin-6-sulfate proteoglycans which together constitute about 65% of the cellular (35S) label. Most PG elute from a DEAE-Sephacel column with 4M Gdn HC1 (PG-1, 87%), and elute at Kav 0.12 on Sepharose CL-6B. The PG-1 can be resolved by SDS-PAGE into two fractions. The remainder (PG-2, 13%) elutes from the DEAE-Sephacel column with 4M Gdn HCl/2% Triton X-100 or 2% CHAPS, and has a Kav of 0.07 on Sepharose CL-6B. About 20-25% of the cell (35S) label elutes from DEAE-Sephacel in the wash-through or with 0.23M NaCl, and can be resolved by SDS-PAGE into at least 8 distinct bands which we have tentatively characterized as sulfated glycoproteins. The remainder of the (35S) is in low molecular weight (LMW) material which does not adhere to DEAE-Sephacel and has not been further characterized.Platelets were treated with either thrombin or ADP, and the cells were then separated from the supernatant by centrifugation. The radiolabeled molecules in the supernatant and the cells were analyzed by DEAE-Sephacel and Sepharose CL-6B column chromatography. About 65% of the total cell (35S) was released from the cells by thrombin. Most of this radiolabel adhered to the DEAE-Sephacel column, and was found to be PG-1. The remainder of the released (35S) was about half the LMW material. In contrast, only 10-15% of the (35S)labeled material retained by the cells adhered to DEAE-Sephacel and was found to be PG-2. The remainder of the (35S)-labeled material retained by the platelets was the sulfated proteins and the LMW material. ADP caused release of about 15% of the (35S), and this was found to be in part PG-1 and in part the LMW material, but not PG-2. None of the (35S)-labeled molecules appeared to be degraded during platelet activation. We suggest that the PG-1 represent the a-granule and PG-2 the membrane proteoglycans. The sulfated proteins have not been described previously. Their role is not known, but we hypothesize that they may form part of the negative charge of the glycocalix and thus be part of the reactive surface of the platelet.

scholarly journals Enzymatic Depolimerization of Chitosan for the Preparation of Functional Membranes

2019 ◽  
Vol 2019 ◽  
pp. 1-8 ◽  
Author(s):  
Eva Águila-Almanza ◽  
René Salgado-Delgado ◽  
Zully Vargas-Galarza ◽  
Edgar García-Hernández ◽  
Heriberto Hernández-Cocoletzi
Keyword(s):  
Molecular Weight ◽  
Low Molecular Weight ◽  
Optimal Conditions ◽  
Degree Of Acetylation ◽  
Vis Spectroscopy ◽  
Low Molecular Weight Chitosan ◽  
Chitosan Membranes ◽  
Capillary Viscosimetry ◽  
Functional Membranes

This work reports the study of chitosan depolymerization through the synergy of the Celuzyme® XB enzyme complex; it is composed of cellulase, xylanase, andβ-glucanase. The optimal conditions of temperature, pH, and concentration were determined to verify the depolymerization reaction. The specificity of the enzymes at theβ(1-4) glycosidic link site was checked. Low molecular weight chitosan (64 × 103 g·mol−1) with degree of acetylation 15% was obtained. The depolymerized chitosan products were characterized by infrared spectroscopy, the degree of acetylation was obtained by UV-Vis spectroscopy, and the determination of the molecular weight was obtained by capillary viscosimetry. With the depolymerized chitosan, membranes were formed and their antioxidant and antimicrobial functionality was determined; results show that these properties are dependent on the molecular weight and on the acetylation degree of chitosan.

Effect of Hydrogen Peroxide on the Extraction of Components of Cedar Powder with Tetrabutylphosphonium Hydroxide Aqueous Solution at 60°C

2017 ◽  
Vol 70 (3) ◽  
pp. 322 ◽  
Author(s):  
Sachiko Yamanaka ◽  
Koichi Yoshioka ◽  
Hisashi Miyafuji ◽  
Hiroyuki Ohno
Keyword(s):  
Aqueous Solution ◽  
Hydrogen Peroxide ◽  
Molecular Weight ◽  
Woody Biomass ◽  
Low Molecular Weight ◽  
Hydroxymethyl Furfural ◽  
Mild Conditions ◽  
Initial Stage ◽  
Aqueous Mixture ◽  
Molecular Weight Fractions

We successfully dissolved cedar powder with tetrabutylphosphonium hydroxide ([P4 4 4 4]OH) aqueous solution at 60°C. The dissolution was accelerated by the addition of H2O2. At the initial stage, cellulose was more soluble than hemicellulose and lignin. Both hemicellulose and lignin were gradually dissolved in this solution containing H2O2. Cellulose chains were revealed to be cut into shorter chains in this solution. The lignin network was also found to be partly broken at 60°C. These steps induced components with higher-molecular-weight fractions that cannot be extracted with polar ionic liquids to dissolve. Also, low-molecular-weight fractions such as vanillin and 5-(hydroxymethyl)furfural were found in the resulting solution. Breakage of ether bonds of polysaccharides and lignin and further oxidation were attributed to the active oxygens generated from H2O2. The aqueous mixture reported here is a protocol that can be used to dissolve woody biomass under mild conditions.

Sign in / Sign up

Export Citation Format

Share Document