Synthesis and anticoagulant activity of pectin sulfates

In this article, we describe the first use of trisulfonated sodium amine as a sulfating reagent for preparing pectin sulfate in aqueous solution. The main reaction parameters that were expected to affect the degree of substitution (DS) were studied. The optimal reaction conditions for the synthesis of pectin sulfate were found to be as follows: the pH of the reaction medium, the reaction temperature, the reaction time, and the ratio of the mole of sodium nitrite (n_NaNO2) to the mass of pectin (m_pectin) were 6, 60°C, 12 h, and 2.5/190 mol/g, respectively. Pectin and pectin sulfate were characterized by Fourier transform infrared (FTIR) spectroscopy and ¹³C‐NMR. The FTIR spectra showed the characteristic absorptions of sulfate ester bonds at 1264 and 830 cm^?1. Furthermore, the anticoagulant activity of pectin sulfates with different DSs, concentrations, and molecular weights were investigated with respect to the activated partial thromboplastin time (APTT), thrombin time (TT) and prothombin time. The clotting assay indicated that the pectin sulfate prolonged APTT and TT through inhibition of the activity of antithrombin. These results suggest that the introduction of sulfate groups into the pectin structure improved its anticoagulant activity. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012     

高取代度羧甲基淀粉钠制备的研究

采用丙酮溶剂法合成高取代度CMS。实验中研究了物料配比、加水量、反应温度和反应时间对取代度（DS）的影响,从而确定合成高取代度CMS的工艺条件。     

Preparation and characterization of carboxymethyl starch under ultrasound‐microwave synergistic interaction

Using native cassava starch as raw materials, carboxymethyl starch (CMS) was prepared by ethanol solvent method under the ultrasound‐microwave synergistic interaction. And the structure of CMS was characterized employing Fourier transform infrared (FTIR) spectrometer, scanning electron microscopy (SEM), X‐ray diffraction (XRD) and thermogravimetric analyzer. Typically, the optimal synthesis conditions for the preparation process confirmed by orthogonal experiment L₁₈ (6¹ × 3⁶) were shown as follows: the ultrasonic treatment temperature was fixed to 35°C and two steps alkalization was employed; the ultrasonic time was 40 min before alkalizing and the ultrasonic power was 220 W; the amount of sodium hydroxide was 8.8 g, the microwave alkalization time was 2 min; the amount of monochloroacetic acid was 11.34 g; the amount of 95% (v/v) ethanol was 70 mL; the microwave etherification time was 3 min. The degree of substitution of prepared CMS was 1.089 ± 0.041, which was increased 30.4% compared with the prepared sample without ultrasound‐microwave synergistic treatment. FTIR results showed that the strong ? COO? characteristic absorption peaks of the stretching vibration were observed at 1613 and 1421 cm^?1, which proved that the carboxymethylation of cassava starch was occurred. SEM results suggested that there were many cracks and dents on CMS granules; and, XRD results indicated that the carboxymethylation of starch occurred both in amorphous region and crystalline region, the noticeable damage of crystalline region by carboxymethylation was observed. Thermogravimetric analysis (TG) and derivative TG showed that thermal stability of CMS changed better compared with native starch. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40906.     

Adsorption mechanism of copper ions in aqueous solution by chitosan–carboxymethyl starch composites

Based on the structural characteristics of chitosan (CTS) and carboxymethyl starch (CMS)， CTS–CMS composites were prepared by crosslinking. The composites had a plurality of reactive functional groups such as  NH₂,  NH₃⁺,  COOH, and  OH and are applied to the adsorption of Cu²⁺ in aqueous solution. The adsorption capacity and stability in acidic solution of the composites were preferable to that of raw material. The effects of temperature, contact time, initial concentration, and pH on the adsorption of Cu²⁺ were investigated. Infrared spectroscopy, scanning electron microscope–energy dispersive spectrometer, X-ray diffraction, and X-ray photoelectron spectroscopy were used to explore the adsorption mechanism. The experiment showed that chemisorption and physisorption coexisted in the adsorption process. It is promising to apply this adsorbent to remove the metal ions in wastewater. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020 , 137, 48636.     

高取代度羧甲基淀粉钠的合成

以淀粉为原料,乙醇为溶剂,研究了淀粉与氢氧化钠,氯乙酸进行醚化反应合成羧甲基淀粉钠的合成工艺中氯乙酸用量,氢氧化钠用量,反应时间,反应温度等对产品对产品取代度的影响,得到了适宜的反应条件,所得产品的DS（取代度）大于0．8。     

Starch derivatives of a high degree of functionalization. VI. Multistep carboxymethylation

For the first time, carboxymethyl starch (CMS) samples with a very high degree of substitution (DS_CM = 2.1) were synthesized by multistep carboxymethylation under heterogeneous reaction conditions in methanol/water with sodium hydroxide and monochloroacetic acid as an etherifying agent. The stepwise increase in the total DS_CM value gradually decreased with an increasing DS_CM value of the starting polymer. The determination of the functionalization pattern of CMS by ¹H‐NMR spectroscopy after chain degradation indicated a high preference for 2‐O‐substitution. The distribution of the carboxymethyl functions was in the order O‐2 ? O‐6 > O‐3. A detailed analysis of the depolymerized sample by means of high‐performance liquid chromatography and capillary electrophoresis revealed a monomer composition that was in very good agreement with the statistical model of Spurlin. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 743–752, 2002     

Physicochemical properties and bioactivity of brown seaweed fucoidan prepared by ultra high pressure-assisted enzyme treatment

The effects of ultra-high pressure (UHP, 100 MPa, 40, 24 h) processing and enzyme treatment on the physicochemical properties and anticoagulant activity of fucoidan obtained from Undaria pinnatifida sporophyll (UPS) were investigated. Crude UPS fucoidan (F _UPS ) with an average MW of 877 kDa was slightly depolymerized by UHPassisted Tunicase treatment, yielding fucoidan with a lower MW (600–800 kDa). UHP-enzyme treatment decreased the sulfate, fucose and galactose contents of F _UPS but increased its glucose content. From FT-IR spectrum, UHP-enzyme treatment was found not to cause a structural change on S=O and C-O-S. After UHP-enzyme treatment, the sulfate content and average MW of F _UPS decreased with the increase of Tunicase concentration. It was found that among the UHP-enzyme-treated fucoidans, F _UPS -T0.3-U (Tunicase 0.3% treatment+UHP treatment) possessed the highest anticoagulant activity. F _UPS -T0.3-U appeared to inhibit blood coagulation via intrinsic pathway. With the increase of sulfate content in F _UPS , activated partial thromboplastin time (APTT) and thrombin time (TT) showed a tendency of increase. APTT and TT had the highest values in F _UPS -T0.3-U in which the sulfate concentration was 24%, but on the contrary decreased at a sulfate concentration of above 24%. This result indicates that there is an optimum sulfate concentration for the anticoagulant activity of fucoidan. Consequently, UHP-assisted enzymatic treatment was found to be helpful for the improvement of anticoagulant activities of fucoidan.     

Intermediate accumulation and efficiency of anaerobic digestion treatment of surfactant (alcohol sulfate)‐rich wastewater at increasing surfactant/biomass ratios

Textile (eg cotton) finishing industry wastewater is characterised by high concentrations of surfactants (up to 2 g dm^?3) and of readily biodegradable biopolymers (COD 5–15 g dm^?3). The anionic surfactant decyl sulfate (DS) was chosen as model surfactant and soluble starch (size) as model compound for the readily biodegradable fraction of the wastewater. Twenty‐two batch experiments with increasing DS/biomass ratio (and starch/biomass ratio) were started simultaneously. Biomass concentrations ranged from 50 to 15 000 mg dm^?3. Minor inhibition effects were found for the surfactant degradation itself at all DS/biomass ratios (maximum biodegradation rate 7.7 mg_DS g_biomass^?1 h^?1). The starch hydrolysis started without a lag‐phase at DS/biomass ratios of up to 0.15 g_DS g_biomass^?1. The lag‐phase was prolonged to about 100 h at a very high DS/biomass ratio (3 g_DS g_biomass^?1). The relative importance of the accumulated intermediates was dependent on the DS/biomass ratio. Above 0.3 g_DS g_biomass^?1 10% of the substrate organic carbon accumulated as ethanol, but no ethanol accumulation was observed at low DS/biomass ratios. Moderate DS/biomass ratios caused a considerable delay of the methanogenesis; high DS/biomass ratios prevented the methanogenesis almost completely. © 2002 Society of Chemical Industry     

Cationic starch iodophores

Cross‐linked cationic starches N‐(2‐hydroxyl)propyl‐3‐trimethyl ammonium starch chloride (CQS chloride), N‐(2‐hydroxyl)propyl‐3‐trimethyl ammonium starch iodide (CQS iodide), and N‐(2‐hydroxyl)propyl‐3‐trimethyl ammonium starch iodide–iodine (CQS triiodide) with the degree of substitution (DS) according to cationic groups from 0.04 to 0.62, as well as cross‐linked starch–iodine complexes were synthesized and tested as potential antibacterial agents. Cationic starch iodine derivatives were obtained during ion exchange reaction between CQS chloride and iodide or iodide–iodine anions in aqueous solutions. CQS_DS≤0.3 chloride can form several types of iodine complexes, such as the blue amylose–iodine inclusion complex and ionic CQS⁺I^?·(I₂)_m complex (m ≥ 1). The antibacterial activity of modified starches–iodine samples against different pathogenic bacterial cultures and contaminated water microorganisms was evaluated. CQS chloride and CQS iodide were found to be bacteriostatic. A strong antibacterial activity was characteristic of CQS triiodides in which molecular iodine is present in both ionic and inclusion complexes. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013     

Synthesis of smart core-shell polymer in supercritical carbon dioxide

Herein we report a new and simple method that has been developed to prepare smart polymeric microgels consisting of temperature-sensitive cores with pH-sensitive shells. The microgels were obtained directly from one step seed polymerization of N-isopropylacrylamide and N,N-methylenebisacrylamide from water-soluble biopolymers containing carboxymethyl groups in supercritical carbon dioxide. The effect of initial concentration of initiator, crosslinker, and carboxymethyl starch (CMS) dose as well as reaction pressures on the yield and morphology of the resulting polymer were investigated. CMS and crosslinker worked effectively as surfactant to some extent. PNIPAM/CMS particles with diameters in 100 nm and narrow particle size distribution were produced in supercritical carbon dioxide, in high yield and in short reaction times.     

Investigations on esterification reactions of starches in 1‐N‐butyl‐3‐methylimidazolium chloride and resulting substituent distribution

The ionic liquid (IL) 1‐N‐butyl‐3‐methylimidazolium chloride ([C₄mim]⁺Cl^?) was used as solvent for different esterification reactions of the biopolymer starch. Therefore, maize starches with varying content of amylose were used. Different carboxylic acid anhydrides were applied to esterify starch with a degree of substitution (DS) in the range of 0.7–3.0. For example, starch acetates with the mentioned DS are accessible within 30 min at a 105°C‐reaction temperature. The DS distribution of starch acetates synthesized in IL was compared with the common starch acetate synthesis of Mark and Mehltretter. Also, a consideration of starch acetates and cellulose acetates synthesized in [C₄mim]⁺Cl^? is given. The starch esters were characterized by means of Raman spectroscopy for qualitative‐ and nuclear magnetic resonance spectroscopy for quantitative determination of the functionalization pattern. Moreover, the molecular mass distribution was determined after saponification by means of GPC‐MALLS. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009     

Synthesis and application of modified starch as a shell–core main adhesive in a foundry

To be used as an alternative adhesive for sand cores in a foundry, a solid water‐soluble modified starch [carboxymethyl starch (CMS)] was synthesized by a new dry reaction process. With this process, a series of CMS products was obtained with degrees of substitution (DSs) ranging from 0.25 to 0.78 at a high reaction efficiency and characterized with regard to their molecular structure and aqueous solution viscosity. On the basis of the dry synthesis of CMS, the properties of CMS‐bonded shell–core sand were investigated, and practical production experiments were carried out. The results show that there was a new sharp peak in the infrared spectrum that represented the carboxymethyl groups and formation of CMS. The viscosity of the CMS aqueous solution increased with increasing DS and amount of CMS. When DS was in the range 0.3–0.5 and the mass fraction was 5–7%, the CMS aqueous solution had a suitable viscosity, which was helpful for the improvement of the properties, such as flowability, permeability, and strength, of the CMS core sand. In addition, a CMS shell–core with an appropriate wall thickness (10–20 mm) for the purpose of obtaining both sufficient strength and permeability could be made with the CMS‐bonded core sand and a hot‐core‐box process. The final pouring results prove that high‐quality iron castings with smooth inner cavities could be produced with the CMS‐bonded shell–core and that it (namely the CMS‐bonded shell‐core) could be used as a replacement for the furan resin‐bonded sand core. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010     

玉米羧甲基淀粉崩解剂的合成及性能改进

采用玉米淀粉为原料,以环氧氯丙烷为交联剂、氢氧化钠和氯化铵为复合催化剂、氯乙酸为醚化剂复合变性合成用作药片崩解剂的羧甲基淀粉,探讨了各种反应条件对淀粉的取代度、膨润性能及反应效率的影响,反应效率提高,反应时间大大缩短。原料最佳配比:n(脱水葡萄糖单元)∶n(环氧氯丙烷)∶n(氯乙酸)∶n(氢氧化钠)=1∶0.4∶0.6∶1.2,反应温度60°C左右,反应时间1～2h。     

Carboxymethyl sago pulp/carboxymethyl sago starch hydrogel: Effect of polymer mixing ratio and study of controlled drug release

Carboxymethyl sag o pulp (CMSP)/carboxymethyl sago starch (CMSS) hydrogel was synthesized by electron beam irradiation. In the series of hydrogels prepared, 40%/20% CMSP/CMSS hydrogel had the highest gel fraction. The swelling capacity of CMSP/CMSS hydrogel was found to be highest in distilled water, followed by pH 11, pH 7.4, and pH 1.2. Scanning Electron Microscope photographs revealed that the drug‐loaded hydrogel had a smoother surface than unloaded hydrogel. Fourier Transform Infrared and Differential Scanning Calorimetry analysis showed the absence of interaction between the hydrogels and the drug. All drug‐loaded hydrogels had drug encapsulation efficiency between 63% and 69%. CMSP/CMSS hydrogel swelled and allowed the release of drug at pH 7.4. These properties qualify the hydrogel as a potential candidate for controlled drug release at the ocular and colonic regions. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43652.     

Synthesis,Characterization, and Performance of a Novel Polymeric Cationic Surfactant Based on Low Molecular Weight Chitosan and 3‐Chloro‐2‐Hydroxypropyl Dimethyl Dehydroabietyl Ammonium Chloride (CHPDMDHA)

A series of novel polymeric cationic surfactants based on low molecular weight chitosan (LWCS) and 3‐chloro‐2‐hydroxypropyl dimethyl dehydroabietyl ammonium chloride (CHPDMDHA), LWCS‐g‐CHPDMDHA, were obtained by the grafting modification of LWCS with CHPDMDHA as grafting agent. The structure of LWCS‐g‐CHPDMDHA was confirmed by FT‐IR and ¹H NMR, and the degree of quaternizing substitution (DS) of LWCS‐g‐CHPDMDHA was determined according to the results of elemental analysis. The aggregation behavior and surface activities of LWCS‐g‐CHPDMDHA in aqueous solution were investigated by transmission electron microscopy (TEM) and determination of surface tension, respectively. The experimental results showed that the DS and molecular weight (M_w) of LWCS have significant influence on the critical micelle concentrations (CMC) and the surface tensions at the CMC (γ_cmc). The shape of aggregates changed with the variation of concentration of LWCS‐g‐CHPDMDHA in aqueous solution. When the LWCS‐g‐CHPDMDHA was utilized as an emulsifier, the increase of DS of LWCS‐g‐CHPDMDHA and M_w of LWCS were favorable for improving the stability of emulsions composed of water and benzene.     

蜡质玉米羧甲基淀粉的合成与表征

以蜡质玉米淀粉为原料,用乙醇溶剂法制备了蜡质玉米羧甲基淀粉(CMS)。考察了碱化时间、醚化反应温度、醚化反应时间、n(NaOH)/n(淀粉)、n(ClCH2COONa)/n(淀粉)对CMS粘度的影响。结果表明,在醚化反应时间2.5 h,n(NaOH)/n(淀粉)为0.4,n(ClCH2COONa)/n(淀粉)为1.2,醚化反应温度65℃,碱化时间为50 min的最佳反应条件下制得的CMS粘度为1 490 mPa.s。同时发现,随着n(ClCH2COONa)/n(淀粉)的增大,CMS粘度表现出先增大后减小再增大,最后减小的趋势,对其进行了分析。     

Chelation of chitosan derivatives with zinc ions. I. O,N‐carboxymethyl chitosan

The chelation between O,N‐carboxymethyl chitosan (ONCMCh) and zinc sulfate in aqueous solution was studied by kinetic experiments and characterized by inductively coupled plasma (ICP) and UV spectrophotometry. The experimental data indicated that the chelating processes were greatly controlled by the reaction conditions (i.e., reaction time, temperature, and Zn²⁺ ionic and ligand concentrations). The consequence of chelating Zn²⁺ onto ONCMCh was the formation of complexes with different solubilities. The favorable complexes for ONCMCh‐Zn²⁺ chelate were at the low zinc ionic and ligand concentrations, as well as at the appropriate temperature. The evidence provided by the kinetic parameters and the changes in zinc concentration by ICP analysis further confirmed the plausible complexing mechanisms. While the formation of water‐soluble products was occasioned by the electrostatic attraction mechanism, the water‐insoluble products were predominantly formed by chelation of Zn²⁺ with O,N‐carboxymethyl chitosan. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 77: 2246–2253, 2000     

Preparation, characterization and antimicrobial activity of quaternized carboxymethyl chitosan and application as pulp-cap

Quaternized carboxymethyl chitosan (QCMC) was prepared from which carboxymethyl chitosan (CMC) was prepared from chitosan first, then N-quaternary ammonium group was introduced by the reaction of CMC with 2, 3-epoxypropyl trimethylammonium. The structures of the derivatives were characterized by FT-IR, XRD, ¹³C NMR, ¹H NMR and gel permeation chromatography. In vitro antimicrobial activities of QCMC were evaluated against Escherichia coli, which is a Gram-negative bacterium, and Staphylococcus aureus, which is a Gram-positive bacterium. In compared with carboxymethyl chitosan (CMC) and quarternary chitosan (QC) of the same degree of substitusion (DS), we found that QCMC has stronger antimicrobial activity. Then we went deep into study of the relationship between their structure and antimicrobial activity, found that the DS of CMC do little effect to their antimicrobial activity, but as the increase of their DS of quaternization or the decrease of their molecular weight, the antimicrobial activity of QCMC become stronger. QCMC was complexed with calcium hydroxide as pulp-cap. Animal experiment results indicated that QCMC can strongly induce reparative dentine formation and showed a better ability in dentin inducing compared with calcium hydroxide.     

半干法合成崩解剂羧甲基淀粉及其性能研究

采用半干法合成药片崩解剂羧甲基淀粉（ＣＭＳ）。考察了碱和一氯乙酸用量对ＣＭＳ取代度（ＤＳ）的影响，实验表明ＤＳ随碱及一氯乙酸用量的增加而增加；考察了ＤＳ及ＣＭＳ中游离羧基和成盐羧基比值Ｈ／Ｎａ的改变对ＣＭＳ吸水溶胀性能和崩解性能的影响，实验表明当ＤＳ为０．５６，Ｈ／Ｎａ比值为０．１３～０．１４时，ＣＭＳ具有最佳的吸水溶胀性能和崩解性能。应用Ｘ射线衍射和扫描电镜探索了ＣＭＳ的结构与性能的关系。     

Optimization of preparation conditions of carboxymethyl potato starch through orthogonal experimental design

To optimize the preparation conditions of carboxymethyl potato starch (CMPS), the effects of relevant factors on viscosity (η) of 2% CMPS aqueous solution and degree of substitution (DS) were investigated. These condition parameters included etherification temperature, alkalization and etherification time, water content in the mixed solvent, ratio of liquid volume to starch mass, molar ratio of sodium hydroxide to monochloroacetic acid, and molar ratio of monochloroacetic acid to anhydroglucose unit. After individual parameter influencing η and DS was researched one by one, an orthogonal experiment of L₁₈ (2 × 3⁷) was designed to identify the main factors affecting them. In light of range analysis, the comparative importance of factors impacting η and DS was obtained, separately. Results of variance analysis showed that the most effective factor to control DS was etherification temperature, whereas the influences of all factors on η were not significant. Meanwhile, η and DS of the optimized final product were found to be 12,000 mPa.s and 0.68, respectively. In addition, the structure of CMPS was characterized by Fourier transform infrared (FTIR) spectrophotometer. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009