Starch Backbone Research Articles

Cationic starch derivatives as mucoadhesive and soluble excipients in drug delivery.

The aim of this study was to develop a novel mucoadhesive cationic polymer by introducing primary amino groups to the polymeric backbone of starch. This newly synthesized polymer should exhibit superior properties over chitosan regarding solubility, mucoadhesiveness and cytotoxicity. Increasing amounts of sodium periodate were used to cleave and oxidize vicinal diols under aldehyde formation obtaining three different degrees of modification. In a subsequent step, primary amines were introduced via reductive amination with ammonia. Degree of amination was examined with TNBS-assay and zeta potential measurements. Mucoadhesiveness was investigated by rotating cylinder, tensile studies and rheological measurements. Primary amino groups were successfully attached to the polymer, proven by zeta potential measurements and UV-spectroscopy. Depending on the amount of periodate used in the reaction, coupling rates of up to 514 µmol/g polymer were achieved. All synthesized derivatives showed 100% solubility in a pH range of 1-9. Aminated starch with the highest coupling rate of 514 µmol/g showed a 9.5-fold prolonged retention time on intestinal mucosa and a 2.7-fold higher total work of adhesion on the mucosal tissue compared to chitosan. Furthermore, cytotoxic examinations of all tested polymers showed only a low impact on cell viability after 24 h, whereby starch derivatives possessed even less cell toxic effects than chitosan. Summarizing these results, cationic starch derivatives seem to be promising excipients for mucosal drug delivery with superior properties compared to chitosan, the most examined cationic polymer.

PH and thermo dual-responsive starch-g-P(DEAEMA-co-PEGMA): Synthesis via SET-LRP, self-assembly and drug release behaviors

A novel pH and thermo dual-responsive graft copolymer, starch-graft-poly(N,N-diethyl aminoethyl methacrylate-co-poly(ethylene glycol) methyl ether methacrylate) [starch-g-P(DEAEMA-co-PEGMA)], was successfully synthesized through single-electron transfer living radical polymerization (SET-LRP). The structure and molecular weight of the grafted chains were confirmed by 1H NMR. These graft copolymers can self-assemble into micelles with starch backbone and PDEAEMA as the core and PPEGMA as the corona in water at pH 7.4. The critical micelle concentration (CMC) of the graft copolymers varied between 0.0313 and 0.1364 mg/mL, decreasing with an increase in the molecular weight of the grafted chains and the ratio of PDEAEMA and PPEGMA segments. The pH and thermo dual-responsive behaviors of starch-g-P(DEAEMA-co-PEGMA) micelles were investigated by DLS and TEM. As the pH decreasd from 8.0 to 5.5, the micelle sizes continued to increase due to the protonation of the PDEAEMA segments, and as the pH decreased to below 5.5, the micelles began to disassemble, which was verified by TEM observations. Upon heating, the size of the micelles decreased because of the shrinkage of the PDEAEMA segments. The pH and thermo dual-responsive behaviors of the starch-g-P(DEAEMA-co-PEGMA) micelles are reversible. Doxorubicin (DOX), a hydrophobic drug, was encapsulated in the micelles, and in vitro release from the drug-loaded micelles displayed good pH-responsive behavior.

PH‐responsive squeezing polysaccharidic nanogels for efficient docetaxel delivery

In this study, we report pH‐responsive polysaccharidic nanogels comprising starch grafted with 3‐(diethylamino)propylamine (DEAP, as an inner soft nanogel core) and poly(ethylene glycol) (PEG, as an outer hydrophilic nanogel shell). Here, the DEAP moieties (pKb ~ pH 7.0) enhance the lipophilicity of the nanogel core at pH 7.4, improving the loading efficiency of an antitumor model drug (docetaxel [DTX]) in the core. However, the DEAP moieties could be protonated below pH 7.0, resulting in the mediation of ion‐dipole interactions with hydroxyl groups abundant in starch backbone. This event causes the electrostatic condensation of the nanogel core and enables the acceleration of drug release by squeezing of the core. We demonstrated that the nanogels selectively release the drug given a weakly acidic pH stimulus. These drug release trends are reversible with changes in pH. As a result, the nanogels are able to efficiently reduce MDA‐MB‐231 tumor cell population in acidic pH environments.

A polysaccharide-based micelle-hydrogel synergistic therapy system for diabetes and vascular diabetes complications treatment

Various glucose-sensitive drug delivery platforms have been developed recently to treat diabetes. However, there is much less work has been reported on treatment of diabetes and vascular diabetes complications simultaneously. In this work, a novel polysaccharide-based micelle-hydrogel synergistic therapy system was fabricated to address this limitation. Zwitterionic dialdehyde starch-based micelles (SB-DAS-VPBA) were synthesized via single electron transfer-living radical polymerization (SET-LRP). Hydrophilic segment sulfobetaine (SB) and hydrophobic segment 4‑vinylphenylboronic acid (VPBA) were grafted to the dialdehyde starch (DAS) backbones. Then, chitosan/dialdehyde starch derivatives (CS/SB-DAS-VPBA) micelle-hydrogel was synthesized by Schiff-base bonds. Insulin and nattokinase were loaded to obtain the micelle-hydrogel synergistic therapy system. In vitro drug delivery and blood clots dissolution behaviors were determined. Results suggest that the micelle-hydrogel synergistic therapy system not only possesses glucose-responsive insulin delivery property, but also provides good thrombolytic capacity. Thus, this micelle-hydrogel synergistic therapy system can be used as a platform for diabetes and vascular diabetes complications treatment.

Influence of crosslinker amount on the microstructure and properties of starch-based superabsorbent polymers by one-step preparation at high starch concentration.

This work concerns how crosslinker amount (N, N'-methylene-bisacrylamide) affects the microstructural, absorbent and rheological features of one-step prepared starch-based superabsorbent polymers at a high starch concentration (0.27:1 w/w starch-water). The increased crosslinker amount evidently altered the microstructure and the absorbent and rheological features. Then, the variations in starch-based superabsorbent polymer properties were discussed from a microstructure viewpoint. Particularly, the higher crosslinker quantity rose the crosslinking density and the ratio (GR) of grafted anhydroglucose unit on starch backbone (from 27% to 52%), but short the average polyacrylamide (PAM) chain length (LPAM). These structural features suppressed the chain stretch within starch-based superabsorbent polymer fractal gels (confirmed by smaller Rg value) and promoted the formation of smaller chain networks, thus weakening the water absorption to the starch-based superabsorbent polymer chain networks. Also, the increased GR and reduced LPAM, with lowered chain extension and elevated crosslinking density, probably decreased the flexibility and mobility of chain segments in starch-based superabsorbent polymer gel matrixes. This caused the enhanced robustness and storage modulus of the gels with reduced chain energy dissipation ability.

Synthesis of a starch–acrylic acid–chitosan copolymer as flocculant for dye removal

ABSTRACTFlocculants prepared with modified natural polymers have recently attracted extensive attention in the field of water treatment. In this work, acrylic acid was successfully grafted onto the backbones of starch and chitosan by free radical polymerization. The synthesis parameters of initiator concentration, reaction temperature, and neutralization degree of acrylic acid were optimized as 0.4 wt %, 50 °C, and 70%, respectively, according to the flocculation performance. The ternary copolymer starch–acrylic acid–chitosan (SAAC) could completely remove Acid Blue 113 from 100 mg/L of simulated wastewater (color removal efficiency 99.7%) at the flocculant dosage of 100 mg/L. The SAAC also had effective flocculation capability in a wide range of flocculant dosages and pH values of wastewater. The ternary copolymer based on two natural polymers has enormous potential as flocculant with its advantages of low price, ecofriendliness, and high performance. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 47437.

Graft copolymeric flocculant using functionalized starch towards treatment of blast furnace effluent

Herein, a novel binary graft copolymeric flocculant [St-g-(PAAm-co-PMETAC)] has been developed using starch, polyacrylamide (PAAm) and poly (2-methacryloyloxy ethyl trimethyl ammonium chloride) (PMETAC). The copolymer has been synthesised by grafting of PAAm and PMETAC chains on starch backbone using free radical polymerization. FTIR and 1H NMR spectral analyses have been used for structural confirmation of developed copolymer. Determination of molecular weight reveals that after grafting of PAAm and PMETAC on starch, the molecular weight as well as radius of gyration have been increased as compared to pristine starch. The surface morphologies of starch and St-g-(PAAm-co-PMETAC) have been assessed by FESEM analysis. TGA/DTG along with MS analyser is able to track the pre-specified compounds over the entire period of degradation temperature. The synthesised graft copolymer i.e. St-g-(PAAm-co-PMETAC) demonstrates brilliant efficiency as flocculant towards the treatment of blast furnace effluent generated in integrated steel plant.

Preparation of amphoteric starch-based flocculants by reactive extrusion for removing useless solids from water-based drilling fluids

In drilling operations, the removal of drill cuttings from recirculating drilling fluids is one of the most important procedures. The high cost and low efficiency of present solid control technologies are two crucial problems that need to be solved urgently. In this work, a series of amphoteric starch-based flocculants (CS-g-DC) were developed to remove useless solids from drilling fluids. These flocculants were synthesized by grafting diallyldimethylammonium chloride (DADMAC) onto carboxymethyl starch (CMS) with different grafting frequencies through reactive extrusion. The physicochemical property of the CS-g-DC products was measured by Fourier-transform infrared (FT-IR) spectroscopy, proton nuclear magnetic resonance (1H NMR) spectroscopy, and zeta potential analysis. It has been found that DMDAAC had been successfully grafted onto the starch backbone and the isoelectric points (IEP) of different CS-g-DC samples increased with grafting degree of DMDAAC (G(DMDAAC)). Three types of clay suspensions (kaolinite, smectite and illite) were used to study the flocculation performance and mechanism of CS-g-DC by turbidity and particle size distribution. The results of these analyses showed that CS-g-DC samples with a G(DMDAAC) higher than 98% flocculated well all three clay suspensions depending on charge attraction and bridging mechanism. The flocculation performance of CS-g-DC was also evaluated in drilling fluids from a drilling site by mineral content analysis. The results showed that these CS-g-DC samples with appropriate G(DMDAAC) could remove useless solids from the drilling fluids effectively, indicating it could be used as flocculants for drilling fluids reuse or recirculation during drilling operation.

Evaluation of the structural morphology of starch-graft-poly(acrylic acid) on its scale-inhibition efficiency

The development of phosphorus-free and biodegradable scale inhibitors has been paid considerable attention. Two series of starch-graft-poly(acrylic acid) (St-g-PAA) samples with different grafting ratios and grafted-chain distributions, that is, the number and length of grafted PAA chains on the starch backbone, were designed and prepared in this study. Fourier transform infrared and 1H nuclear magnetic resonance spectra were used to further characterize the molecular structures of the St-g-PAAs. In addition to dose, the effects of the structural morphologies of St-g-PAA, namely, grafting ratio and grafted-chain distribution, on the scale-inhibition performance against calcium carbonate were investigated systematically. Structural morphology significantly influenced the scale-inhibition performance of St-g-PAA. St-g-PAA with relatively low grafting ratio (≤97%) displayed better scale-inhibition effect than samples with similar grafted-chain distributions. Meanwhile, under the similar grafting ratios, samples with higher number of branched chains with shorter grafted chains displayed better antiscaling performance. Thus, higher scale-inhibition rate and lower corresponding optimal dose were obtained. Different scale-inhibition mechanisms were involved in the effects of the structural morphology. These mechanisms were investigated in detail from the molecular levels using scanning electron microscopy and X-ray diffraction.

Copper-mediated homogeneous living radical polymerization of acrylamide with waxy potato starch-based macroinitiator

Cu0-mediated living radical polymerization (Cu0-mediated LRP) was employed in this research for the synthesis of starch-g-polyacrylamide (St-g-PAM). The use of a controlled radical grafting technique is necessary, as compared to the traditional free-radical polymerization methods, in order to obtain a well-defined structure of the final product. This is in turn essential for studying the relationship between such structure and the end-properties. Waxy potato starch-based water-soluble macroinitiator was first synthesized by esterification with 2-bromopropionyl bromide in the mixture of dimethylacetamide and lithium chloride. With the obtained macroinitiator, St-g-PAM was homogeneously synthesized by aqueous Cu0-mediated LRP using CuBr/hexamethylated tris(2-aminoethyl)amine (Me6Tren) as catalyst. The successful synthesis of the macroinitiator and St-g-PAM was proved by NMR, FT-IR, SEM, XRD and TGA analysis. The molecular weight and polydispersity of PAM chains were analyzed by gel permeation chromatography (GPC) after hydrolyzing the starch backbone. Monomer conversion was monitored by gas chromatography (GC), on the basis of which the kinetics were determined. A preliminarily rheological study was performed on aqueous solutions of the prepared materials.

Influence of Chain Structures of Starch on Water Absorption and Copper Binding of Starch‐Graft‐Itaconic Acid Hydrogels

Bio‐based hydrogels destined for use as low cost renewable biosorbents are synthesized. The impact of the two components of starch, amylose, and amylopectin, on the properties of the hydrogels is assessed. Hydrogels are synthesized by solution based graft copolymerization of itaconic acid monomers on a corn starch backbone in the presence of an acrylamide crosslinker and the potassium persulfate/sodium bisulfite redox initiator pair. Three types of corn starch are used: normal corn starch, waxy starch, and high amylose starch. The amylose:amylopectin ratios are: 27:73 for normal starch (NS), 70:30 for high amylose starch (HAS), and 0:100 for waxy starch (WS). Swelling tests performed in a variety of solutions show no significant differences in swelling capacity among the hydrogels. The hydrogels also perform similarly in copper adsorption tests. Overall, these results indicate that native corn starch is as effective as amylopectin and amylose‐rich starch.

Desizability of the Grafted Starches Used as Warp Sizing agents

An attempt is made to examine the effect of the consitituent units in the branches grafted onto the backbones of starch on the desizability of grafted starches for warp sizing. The starches investigated include starch‐g‐polyacrylamide, starch‐g‐poly(acrylic acid), starch‐g‐polyacrylate, and starch‐g‐polymethacrylate, which are synthesized via graft copolymerization in water using Fe2+‐H2O2 initiators. The desizability is evaluated by enzyme, alkali, and oxidant desizings in terms of desizing efficiency, water swellability of starch film, and the time for breaking the starch film in water. It is found that the constituent units play an important role in desizability. Hydrophilic units are superior to hydrophobic ones in improving desizability. For the (meth)acrylate units, the increase in the number of carbon atoms in alkyl esters and the presence of α‐methyl show adverse impact on desizability. An increase in the grafting ratio of starch‐g‐polyacrylamide favors improvement of the desizabity whereas the increase in the ratio of starch‐g‐poly(methyl acrylate) reduces the desizabity. Of the three desizing methods considered here, oxidant and enzyme desizings have superior desizability to alkali one.

Starch Derivatives Bearing Aromatic Sulfonated Functional Groups

Starch derivatives with anionic functional groups have attracted a lot of attention because of their potential in the industrial applications. Commonly, anionic starch derivatives possess gelatinization temperatures lower than that of native starch, which is broadening its applications in industrial processes operated at low temperature. Here, new starch derivatives containing sulfonated functional groups are prepared through intermediate triazinyl compounds. Four different bridging compounds are synthesized and characterized via spectral analysis. The sulfonated triazinyl compounds are reacted with native starch to obtain different densities of sulfonic acid groups on the starch backbone. Native starch is reacted with mono/dichlorotriazine‐4‐aminobenzene‐sulfonic acid and mono/dichlorotriazine‐4‐aminobenzene 1,3‐disulfonic acid. The sulfonic acid groups are introduced in different degrees of substitutions (0.043, 0.032, 0.006, and 0.008) which causescharge repulsion along the starch chains and results in keeping chains stretched and therefore less affected by pH and temperature. Ultimately, the produced anionic starch derivatives possess gelatinization temperatures lower than that of native starch.

Glucose-responsive zwitterionic dialdehyde starch-based micelles with potential anti-phagocytic behavior for insulin delivery

Both blood stability and glucose responsiveness for carriers are the most important issues in insulin controlled release studies. However, few reports focus on reducing macrophage response performance for drug carriers themselves. Zwitterionic self-assembled micelles mitigated recognition by immune cell has evolved to address this limitation. In this work, novel zwitterionic dialdehyde starch-based micelles, sulfobetaine (SB) as the hydrophilic shell, and 3-aminophenylboronic acid (APBA) as glucose-responsive groups to the dialdehyde starch (DAS) backbones (SB-DAS-APBA) with glucose-responsive behavior were developed. Insulin release from the nanocarriers is sensitive to the different concentration of the glucose, rapidly at the condition of 3 mg/mL of glucose at pH 7.4. Methyl thiazolyl tetrazoliumviability (MTT) assay confirmed that zwitterion micelles were cytobiocompatible and low cytotoxic activity with A549 cells. For comparison, PEGylation micelles, monomethyl ether (mPEG) as the hydrophilic shell, and APBA as glucose-responsive groups to the DAS backbones (mPEG-DAS-APBA), were also synthesized. Confocal laser scanning microscopy (CLSM) and flow cytometry results displayed that PEGylation and zwitterion coating micelles have different recognition processes in contact with macrophages. After 4 h, doxorubicin (Dox) fluorescence of the Dox-loaded mPEG-DAS-APBA micelle groups were mostly located in nuclei. However, SB-DAS-APBA micelle groups were slightly detected in both nuclei and cytosol. In addition, the fluorescence signals of mPEG-DAS-APBA micelles showed enhanced trend than that of SB-DAS-APBA micelles in macrophage cells. These results suggest that, as drug carriers, zwitterionic self-assembled micelles SB-DAS-APBA not only possessed glucose-responsive insulin delivery property, but also reduced macrophage response performance.

A Study of Moisture Sorption and Dielectric Processes of Starch and Sodium Starch Glycolate : Theme: Formulation and Manufacturing of Solid Dosage Forms Guest Editors: Tony Zhou and Tonglei Li.

This study explored the potential of combining the use of moisture sorption isotherms and dielectric relaxation profiles of starch and sodium starch glycolate (SSG) to probe the location of moisture in dried and hydrated samples. Starch and SSG samples, dried and hydrated, were prepared. For hydrated samples, their moisture contents were determined. The samples were probed by dielectric spectroscopy using a frequency band of 0.1 Hz to 1 MHz to investigate their moisture-related relaxation profiles. The moisture sorption and desorption isotherms of starch and SSG were generated using a vapor sorption analyzer, and modeled using the Guggenheim-Anderson-de Boer equation. A clear high frequency relaxation process was detected in both dried and hydrated starches, while for dried starch, an additional slower low frequency process was also detected. The high frequency relaxation processes in hydrated and dried starches were assigned to the coupled starch-hydrated water relaxation. The low frequency relaxation in dried starch was attributed to the local chain motions of the starch backbone. No relaxation process associated with water was detected in both hydrated and dried SSG within the frequency and temperature range used in this study. The moisture sorption isotherms of SSG suggest the presence of high energy free water, which could have masked the relaxation process of the bound water during dielectric measurements. The combined study of moisture sorption isotherms and dielectric spectroscopy was shown to be beneficial and complementary in probing the effects of moisture on the relaxation processes of starch and SSG.

Fabrication of starch-graft-poly(acrylamide)/graphene oxide/hydroxyapatite nanocomposite hydrogel adsorbent for removal of malachite green dye from aqueous solution

This article reports the efficient removal of malachite green (MG) dye from aqueous solution using a novel polysaccharide-based nanocomposite hydrogel adsorbent (NHA). The NHAs of different compositions were prepared through a simple free radical graft copolymerization of acrylamide (AM) monomer onto starch backbones in the presence of graphene oxide (GO) nano sheets and nono-hydroxyapatite (n-HAp). The surface morphology and chemical properties of the prepared NHAs were fully examined by using FTIR, SEM, TEM, XRD and TGA.The biocompatibility, biodegradability, porosity, water content and water uptake of the synthesized NHAs were also evaluated. The NHA was employed as bioadsorbents for the adsorption of MG dye. The temperature dependence data also revealed that MG sorption process was feasible, spontaneous and endothermic. The MG adsorption rates were described by the pseudo-second-order model. Furthermore, the adsorption isotherm data fitted well with the Langmuir isotherm model with a maximum adsorption capacity of 297mgg−1 for MG dye. The NHA also showed an excellent regeneration capacity after five consecutive cycles of dye adsorption-desorption. According to the results, the prepared NHAs could be environment friendly and promising adsorbents for the adsorption of different cationic dyes from contaminated water.

Transesterification of sago starch and waste palm cooking oil in densified CO2

In this work, the synthesis of biodegradable and yet renewable thermoplastics materials through a transesterification reaction of sago starch and waste palm cooking oil (WPO) in densified CO2 as the solvent is reported. The aim of this research is to investigate the potential used of sago starch and WPO as raw materials in the thermoplastics starch synthesis. The starch esters was successfully synthesized using sago starch and WPO as reagent in densified CO2 as shown from the presence of carbonyl group (C=O, 1743 cm-1) in the FT-IR spectra coupled with the presence of the proton (1H-NMR) of the fatty acid in the starch backbone (0.8 – 2 ppm). The product crystallinity decreases as shown in XRD results and resulting with a change in the thermal properties (melting and crystalline temperature) of the products. In addition, the products show a different granular morphology and a higher hydrophobicity compared with native sago starch. This research shows the potential used of sago starch and WPO in the thermoplastics starch synthesis and opens a new perspective on the product application.

Antibacterial and Structural Properties and Printability of Starch/Clay/Polyethylene Composite Films

A composite of thermoplastic starch (TPS), low-density polyethylene (LDPE) and citric acid-modified montmorillonite (CMMT) was prepared in a twin screw extruder for packaging film application. Starch was first converted to the thermoplastic state by using sorbitol and water. Composite films were produced on a chill roll system and then were modified for printability by grafting of acrylonitrile onto the starch backbone. Antimicrobial property and printability of the films were studied from which the sample with the highest antimicrobial property and the best printability was selected. This optimal sample was then characterized by Fourier transform infrared, thermal gravimetric analysis, differential scanning calorimetry, X-ray diffraction, and scanning electron microscopy. The composite film showed a matrix/dispersed morphology in which LDPE formed a continuous phase and TPS/CMMT nanocomposite particles appeared as dispersed phase. Biodegradability, water absorption, oxygen permeability, tensile strength and transparency of optimal film were also studied. The results indicated very good properties of the produced composite film for packaging application.

Chemical Modification of Potato Starch by Graft Copolymerization with Citronellyl Methacrylate

Chemical modification of potato starch with citronellyl methacrylate monomer, characterization of obtained materials and its physicochemical properties have been presented. The chemical modification of potato starch under the grafting process with citronellyl methacrylate led to the preparation of novel, amphiphilic materials where from 0.3 to ca. 1.6 hydroxyl groups per glycoside unit were replaced by poly(citronellyl methacrylate) chains. The grafting of poly(citronellyl methacrylate) chains onto starch backbone caused considerably changes in the morphology, polarity, solubility, chemical stability, moisture absorbance, gelatinization properties, thermal stability and decomposition mechanism of the prepared copolymers as compared to native potato starch. The influence of the grafting percent on the above mentioned properties as well as on the pyrolysis mechanism was discussed in detail.

Evaluation of the starch-based flocculants on flocculation of hairwork wastewater

China is the world's largest producer of wigs, and the manufacturing generates large quantities of hairwork effluents. Coagulation/flocculation is an important step in the water treatment process. In this study, two versions of starch-based flocculants were successfully prepared through etherification and graft copolymerization, respectively. Starch-3-chloro-2-hydroxypropyl triethyl ammonium chloride (St-CTA-DQ) and starch-graft-poly[(2-methacryloyloxyethyl) trimethyl ammonium chloride] (St-g-PDMC-DQ) both contain strongly cationic quaternary ammonium salt groups, but have differing cationic contents, specifically, the degree of substitution (DS) and grafting ratio (G). Furthermore, the additional functional groups were distributed on different chain sites (the starch backbone for St-CTA-DQ, and the branch chains for St-g-PDMC-DQ). These two flocculants demonstrated superior efficiency for turbidity and UV254 removal in hairwork wastewater as well as better floc properties compared to polyaluminum chloride. The effects of pH, flocculant dose, and cationic group contents (DS and G) were systematically investigated. Consequently, it was determined that a higher cationic content in both the flocculants led to better flocculation performance as well as increased removal rates of both turbidity and UV254. This was primarily due to improved charge neutralization, which highlighted the preference towards a lower optimal dose. In addition, flocculation performance worsened as the pH level increased. Overall, St-g-PDMC-DQ exhibited similar flocculation performance to St-CTA-DQ. However, the wastewater treated by St-g-PDMC-DQ showed lower residual turbidity than when treated by St-CTA-DQ. This was attributed to the distinct branch chain architecture of St-g-PDMC-DQ, which was beneficial for coagulating the uneasily flocculated contaminants in water, such as smaller-sized colloids and water-soluble organic substances. Flocculant structural factors, specifically charge properties and chain architecture, heavily affected the final flocculation performance.