Controlled mechanical and swelling properties of poly(vinyl alcohol)/sodium alginate blend hydrogels prepared by freeze–thaw followed by Ca2+ crosslinking

Poly(vinyl alcohol) (PVA)/sodium alginate (SA) blend hydrogels have immense potential for use as functional biomaterials. Understanding of influences of processing parameters and compositions on mechanical and swelling properties of PVA/SA blend hydrogels is very important. In this work, PVA/SA blend hydrogels with different SA contents were prepared by applying freeze–thaw method first to induce physical crosslinking of PVA chains and then followed by Ca²⁺ crosslinking SA chains to form interpenetrating networks of PVA and SA. The effects of number of freeze–thaw cycles, SA content and Ca²⁺ concentration on mechanical properties, swelling kinetics, and pH‐sensitivity of the blend hydrogels were investigated. The results showed that the blend hydrogels have porous sponge structure. Gel fraction, which is related to crosslink density of the blend hydrogels, increased with the increase of freeze–thaw cycles and strongly depended on SA content. The SA content exerts a significant effect on mechanical properties, swelling kinetics, and pH‐sensitivity of the blend hydrogels. The number of freeze–thaw cycles has marked impact on mechanical properties, but no obvious effect on the pH‐sensitivity of the PVA/SA blend hydrogels. Concentration of CaCl₂ aqueous solution also influences mechanical properties and pH‐sensitivity of the blend hydrogel. By altering composition and processing parameters such as freeze–thaw cycles and concentration of CaCl₂ aqueous solution, the mechanical properties and pH‐sensitivity of PVA/SA blend hydrogels can be tightly controlled. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012     

Facile preparation and characterization of sodium alginate/graphite conductive composite hydrogel

Conductive composite hydrogels based on sodium alginate (SA) and graphite were fabricated by a facile method via dispersing homogeneously conductive graphite into SA hydrogel matrix. The hydrogel was formed by in situ release of Ca²⁺ from Ca–EDTA, thus eliminating the multistep reactions and tedious purification compared to the previous work. Raman spectra, scanning electron microscopy (SEM), X‐ray diffraction (XRD), and thermogravimetric analysis (TGA) were used to characterize the structure, crystalline nature, and thermostability of SA/graphite composite hydrogels. The SA/graphite composite hydrogels exhibited the improved network and layer‐type structure. The thermal stability of the hydrogel decreased slightly after the graphite was incorporated into the SA hydrogel matrix regardless of the content of graphite. The enhanced mechanical strength of SA/graphite composite hydrogel was achieved via increasing the f value (i.e., [Ca²⁺]/[COO^‐ in alginate]) and lowering graphite content. The conductivity of the composite hydrogels could be varied in a broad range, reaching up to 10⁻³ S/cm, mainly depending on the content of graphite and the f value. POLYM. COMPOS., 37:3050–3056, 2016. © 2015 Society of Plastics Engineers     

Preparation a novel pH‐sensitive blend hydrogel based on polyaspartic acid and ethylcellulose for controlled release of naproxen sodium

Hydrogels based on pH‐sensitive polymers are of great interest as potential biomaterials for the controlled delivery of drug molecules. In this study, a novel, pH‐sensitive hydrogel was synthesized by poly(aspartic acid) (PASP) crosslinked with 1,6‐hexanediamine and reinforced with ethylcellulose (EC). The loading and release characteristics of naproxen sodium (NS) were studied. The PASP–EC blend hydrogels had pH‐sensitive characteristics and were strongly dependent on the pH value. The release kinetics for NS from the PASP–EC blend hydrogels and PASP hydrogel were evaluated in simulated gastric fluid (pH = 1.05) and simulated intestinal fluid (pH = 6.8) at 37°C. The results showed that the drug‐loaded hydrogels were resistant to simulated gastric fluid, and hence, they could be useful for oral drug delivery. Compared with the PASP hydrogel, the PASP–EC blend hydrogels showed a lower release rate of NS in the same pH conditions. It was evident that the presence of hydrophobic groups (EC) retarded the release of NS and led to sustained release. The kinetics of NS release from the drug‐loaded hydrogels conformed to the Korsmeyer–Peppas model. The release exponent of the model was 0.7291, which indicated multiple drug release. The PASP–EC blend hydrogels were biodegradable and pH sensitive; there would be a wide range of applications for them in controlled drug‐delivery systems. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009     

Construction and evaluation of the hydroxypropyl methyl cellulose-sodium alginate composite hydrogel system for sustained drug release

We prepared a hydroxypropyl methyl cellulose-sodium alginate (HPMC-SA) composite hydrogel with a membrane covering the semi-interpenetrating network based on a semi-synthetic polymer hydroxypropyl methyl cellulose (HPMC) and a natural polymer sodium alginate (SA) by Ca²⁺ crosslinking and polyelectrolyte complexation with chitosan (CS) covering the hydrogel surface. The physiochemical properties of HPMC-SA hydrogels were evaluated by scanning electron microscopy, infrared spectrum, X-ray diffraction, and thermogravimetric analysis. The swelling ratio of the HPMC-SA composite hydrogel in simulated gastrointestinal fluid was measured. The drug release behavior of the HPMC-SA composite hydrogel for macro-molecular and small-molecule drugs was evaluated by using bovine serum albumin, metformin hydrochloride, and indomethacin as model drugs. The results showed that the HPMC-SA hydrogel had good water absorption and degradability, an increased swelling ratio of 55, and a prolonged time for maximum swelling degree of 50 h. Moreover, the hydrogel exhibited higher drug-loading capacity and improvements in the sustained release of bio-macromolecules, demonstrating its potential as a drug carrier for biomedical applications.     

Alginate/carboxymethyl chitosan composite gel beads for oral drug delivery

This paper reports the synthesis of pH-sensitive gel beads derived from alginate (SA) and carboxymethyl chitosan (CMCS) for drug delivery. The composite SA/CMCS gel beads were prepared by dual ionic gelation: one ionic gelation between SA and Ca²⁺ and another one between CMCS and β-Sodium glycerophosphate (β-GP). The structure properties of hydrogel beads were characterized by SEM, IR and TG technique. The influence of the polymer composition and cross-linkers on the gel swelling property was investigated. When the concentration of CMCS and SA were 3 % and the volume ratio was 1:2, the swelling rate of gel beads crosslinked by β-GP and CaCl₂ solution can increase up to 31.2 and the swelling time can reach 10.5 h. In the drug release study, bovine serum albumin (BSA) was chosen as model drugs. The results indicated that BSA released slowly from the gel beads at pH 1.2 and the release ratio was about 10 %. At pH 7.4, the amounts of BSA released increased significantly as compared to those released at pH 1.2 and the total release time was extended to 11 h. The composite gel system demonstrates sustained release profile and pH sensitivity, which can be considered as good candidates for oral drug delivery systems.     

Synthesis and characterization of novel pH-, ionic strength and temperature- sensitive hydrogel for insulin delivery

A series of novel silane crosslinked hydrogel was prepared from kappa carrageenan (KC), acrylic acid (AA) using vinyltriethoxysilane (VTESi). Potassium persulphate initiated the grafting and copolymerization reactions between reactants. In addition, the condensation of the hydroxyl groups of KC and VTESi resulted into crosslinking. Novelty of this work is the use of VTESi as crosslinker for such a composition of hydrogel. The structure of prepared hydrogels was characterized by Fourier transform infrared spectroscopy. The analysis of spectra confirmed the presence of feed components in the prepared hydrogels. Thermogravimetric analysis showed an increase in the stability of the hydrogels either having high AA contents or crosslinker amount. The effect of feed components, pH (buffer, non-buffer), electrolytic media and temperature on the swelling behaviour of the hydrogels is reported here.Most promising results with high swelling ratio were observed in hydrogel having low monomeric ratio (KC:AA = 1:7). pH response of this hydrogel in acidic and neutral pH makes it suitable for drug delivery application. Insulin, a protein based drug was selected as a model drug. It requires its delivery in small intestine for proper action; therefore its release behaviour was studied in-vitro in simulated stomach and intestinal fluids. The release profile of insulin showed negligible release in simulated gastric fluid (SGF) and sustained release in simulated intestinal fluid (SIF). The obtained results are in good agreement with the swelling response of this hydrogel. The weak structure of this hydrogel makes it preferable for drug delivery, as it is able to get crumbled after releasing the drug for 6 h at neutral pH.     

pH-sensitive hydrogel based on carboxymethyl chitosan/sodium alginate and its application for drug delivery

Carboxymethyl chitosan sodium salt (CMCS)/sodium alginate (SA), a pH-sensitive hydrogel composed of CMCS and SA crosslinked by 1-ethyl-3-(3-dimethyl aminopropyl) carbodiimide (EDC) and N-hydroxysuccinimide, has been evaluated in vitro as a potential carrier for protein drug delivery of bovine serum albumin (BSA). The crosslinked structures, pore morphologies, and mechanical properties of the composite CMCS/SA hydrogel at different pH have been characterized by Fourier-transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), and dynamic mechanical analysis (DMA). The swelling behavior of the prepared hydrogel was assessed at different pH values, 1.2, 4.0, 6.86, 7.4, and 9.0. The in vitro slow release ability of the CMCS/SA hydrogel was assessed at 37°C and pH 1.2 or pH 7.4 to simulate gastrointestinal and mouth environments in vivo. The efficiency was found to be greater than 90% at pH 7.4. The composite CMCS/SA hydrogel showed no cytotoxic effect toward L-929 cells according to the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide test. These findings demonstrate that the composite hydrogel has promising potential for drug delivery. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 46911.     

Macro- and Nanoscale Effect of Ethanol on Bovine Serum Albumin Gelation and Naproxen Release

We report extended ethanol-induced gelation procedures of bovine serum albumin (BSA) at 37 °C and investigate the release behavior of a spin-labeled naproxen derivative (SL-NPX) from these hydrogels. The macroscopic mechanical properties of these gels during formation were studied using rheology, while a nanoscopic, more molecular view was obtained by analyzing the secondary structure of the protein during gelation via infrared (ATR-IR) spectroscopy. To evaluate the potential use of BSA hydrogels in controlled drug delivery, SL-NPX-BSA interaction was investigated in detail by continuous-wave electron paramagnetic resonance (CW EPR) spectroscopy, which provides information on the interaction of the small drug molecules and the hydrogel. In addition to CW EPR spectroscopy, dynamic light scattering (DLS), which provides insight into the size and nature of released components, was applied to characterize the combined influence of incubation time, ethanol, SL-drug, and BSA concentration on release behavior. It was found that the alteration of initial drug loading percentage, hydrogel incubation time as well as BSA and alcohol concentrations affect and thus tune the release rate of SL-NPX from BSA hydrogels. These results lead to the conclusion that BSA hydrogels as controlled release systems offer a remarkable fine-tuning capability for pharmaceutical applications due to the variety of gelation parameters.     

Effect of poly(ethylene glycol)-derived crosslinkers on the properties of thermosensitive hydrogels

Three crosslinkers, poly(ethylene glycol) diacrylate (PEGDA), glycerol ethoxylate triacrylate (GETA) and citric acid-(PEG acrylate)₃ (CA-PEGTA) derived from poly(ethylene glycol) (PEG) were synthesized at first. The three series of poly (N-isopropylacrylamide) (PNIPAAm) hydrogels were prepared by photopolymerization with the crosslinkers and compared with a hydrogel based on commercial crosslinker, N,N′-methylene bis-acrylamide (NMBA). The influence of the crosslinker structures and contents on the swelling behaviour, mechanical properties, and drug release of the hydrogels was investigated. The results showed that the hydrogels based on PEGDA and NMBA exhibited the highest and the lowest swelling ratio, respectively. The content of crosslinker of all hydrogel series showed good thermosensitivity and thermo-reversibility. The critical gel transition temperature (CGTT) appeared at 32 °C for the hydrogel based on NMBA, but appeared at about 34 °C for other hydrogels due to higher hydrophilicity of the crosslinker. In the mechanical properties, three-arms crosslinker GETA and CA-PEGTA led to higher mechanical strength than a linear crosslinker PEGDA. A hydrogel based on GETA (NG6) showed the highest shear modulus of 656.9 kPa and Young’s modulus of 1655.0 kPa. The hydrogels containing higher content of crosslinker revealed lower swelling ratio and higher mechanical strength. In the drug release, the hydrogels with higher swelling ratios showed higher drug absorbed. The highest release percentage of caffeine and vitamin B12 for hydrogel based on PEGDA (NP6) could reach 68.3% and 75.4%, respectively. In addition, the bound water and toxicity of the hydrogels were also investigated.

     

Swelling behaviour and paracetamol release from poly(<Emphasis Type="Italic">N</Emphasis>-isopropylacrylamide-itaconic acid) hydrogels

Copolymer hydrogels of N-isopropylacrylamide and itaconic acid (IA), crosslinked with N,N′-methylenebisacrylamide, were prepared by radical copolymerization. These hydrogels were investigated with regard to their composition to find materials with satisfactory swelling and drug release properties. A paracetamol is used as a model drug to investigate drug release profile of the hydrogels. It was found that the investigated hydrogels exhibited pH- and temperature-dependent swelling behaviour with restricted swelling and lower equilibrium degree of swelling at lower pH values and temperatures above the LCST value of PNIPAM (around 34 °C). The diffusion exponent for paracetamol release indicate that the mechanism of paracetamol release are governed by Fickian diffusion, while in all release media initial diffusion coefficient was lower than late time diffusion coefficient. Furthermore, the paracetamol release rate depends on the hydrogel degree of swelling and it increased in the first stage of diffusion process, whereas was no significant difference thereafter. The presence of the IA moieties incorporated into the network weakened the shear resistance of the hydrogels. In order to calculate the pore size the characteristic ratio for PNIPAM, C _n  = 11.7, was calculated. Based on the pore size, the investigated hydrogels can be regarded as microporous. According to the obtained results swelling behaviour, mechanical properties, drug-loading capacity and the drug release rate could be controlled by hydrogel composition and crosslinking density, which is important for application of the investigated hydrogels as drug delivery systems.     

Photopolymerized hydrogel composites from poly(ethylene glycol) and hydroxyapatite for controlled protein delivery in vitro

The incorporation of hard particles into soft hydrogels can improve the mechanical properties and provide necessary bioactivity to the hydrogels for desired biomedical applications. Hydrogel composites containing hydroxyapatite (HA) are promising materials for orthopedic applications. In this study, injectable poly(ethylene glycol) (PEG) hydrogel precursor solutions containing HA particles and model protein bovine serum albumin (BSA) were synthesized in situ by photopolymerization. In vitro BSA release properties from the hydrogel composites containing various amounts of HA were investigated and discussed. Fourier transform infrared spectroscopy and scanning electron microscopy were employed to investigate the interaction between HA and the hydrogel network and the morphology of the hydrogel composites. It is found that PEG hydrogel composites containing HA sustained the release of BSA for at least 5 days and the presence of HA slowed down BSA release. Photopolymerized hydrogel composites containing HA may find potential use as a drug delivery matrix for orthopedic tissue engineering. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013     

Alginate/BSA/montmorillonite composites with enhanced protein entrapment and controlled release efficiency

Novel pH sensitive alginate–protein–clay composite beads were investigated for the in vitro oral delivery of the model protein, bovine serum albumin (BSA). X-ray diffraction (XRD) results revealed that BSA enter between layers of montmorillonite (MMT) by expanding interlayer distance and finally an exfoliated structure forms in the alginate hydrogel. MMT incorporation increases protein entrapment efficiency to 78%, compared to 40% of conventional alginate beads. The release ratio of BSA from composite beads is 9–13% depending on MMT contents after around a 2 h stay in gastric fluid. More importantly, no BSA release is detected until 60–90 min after the first contact time of beads with gastric solution. The presence of clay in alginate beads prevents burst release in higher pH of intestine by slowing release rate of BSA to 45–55% within around 9 h, resulting in a potential matrix for intestinal release of protein drugs.     

Synthesis of dual physical self-healing starch-based hydrogels for repairing tissue defects

Hydrogels have the potential to simulate and permeate body tissues. They can be used in many biomedical applications, such as drug delivery, wound dressings, contact lenses, synthetic implants, biosensors, and tissue engineering. Despite recent significant advances in hydrogel fabrication, with the introduction of double network hydrogels, with ionic or hydrogen bonds, there is still the challenge of achieving optimal mechanical properties with appropriate self-healing ability. To solve the above problem, in this study, a new type of starch/chitosan/PVA/borax hydrogel was synthesized by adopting the one-pot method. The effect of concentration and ratio of raw materials on the final properties of hydrogels, such as the degree of hydrophilicity, morphology, degradation, mechanical strength, and drug release rate, was investigated. The properties of hydrogels were examined by scanning electron microscopy, thermogravimetric analysis, Fourier-transform infrared spectroscopy, X-ray diffractometry, and contact angle, which confirmed the composite synthesis and uniform distribution of HNT and curcumin. In addition, the composite hydrogel showed excellent mechanical properties. Drug release studies confirmed that the drug is slowly released from the nanocomposite hydrogels. The results showed that starch-based nanocomposite hydrogels could provide appropriate repairing potential for defects exposed to changeable parameters.     

Effect of attapulgite contents on release behaviors of a pH sensitive carboxymethyl cellulose‐g‐poly(acrylic acid)/attapulgite/sodium alginate composite hydrogel bead containing diclofenac

A series of pH‐sensitive composite hydrogel beads, carboxymethyl cellulose‐g‐poly(acrylic acid)/attapulgite/sodium alginate (CMC‐g‐PAA/APT/SA), were prepared by combining CMC‐g‐PAA/APT composite and SA, using Ca²⁺ as the ionic crosslinking agent and diclofenac sodium (DS) as the model drug. The effects of APT content and external pH on the swelling properties and release behaviors of DS from the composite hydrogel beads were investigated. The results showed that the composite hydrogel beads exhibited good pH‐sensitivity. Introducing 20% APT into CMC‐g‐PAA hydrogel could change the surface structure of the composite hydrogel beads, decrease the swelling ability, and relieve the burst release effect of DS. The drug cumulative release ratio of DS from the hydrogel beads in simulated gastric fluid was only 3.71% within 3 hour, but in simulated intestinal fluid about 50% for 3 hour, 85% for 12 hour, up to 90% after 24 hour. The obtained results indicated that the CMC‐g‐PAA/APT/SA hydrogel beads could be applied to the drug delivery system as drug carriers in the intestinal tract. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

Photo‐Induced Hydrogel Formation Based on g‐C3N4 Nanosheets with Self‐Cross‐Linked 3D Framework for UV Protection Application

Composite hydrogels of graphitic carbon nitride nanosheets (CNNS) and polyacrylamide (PAM) with superior UV absorption and visible transparence capabilities are reported. CNNS is employed not only as a photocatalytic initiator to trigger the polymerization of acrylamide, but also as a cross‐linker to 3D connected PAM chains via hydrogen bonds. The obtained CNNS/PAM hydrogels are highly moldable for preparing various forms, and have good mechanical properties, self‐healing ability, and photo‐stability. Furthermore, the composite hydrogels have a wide spectral range for UV absorption compared to conventional UV protective materials. Besides the complete screening of UVB (280–315 nm) in sun radiation, the CNNS/PAM hydrogel film can also filter >95% UVA radiation (315–400 nm) by regulating the coating thickness, meanwhile retaining a high visible transmittance. Therefore, the CNNS/PAM hydrogels have potential applications for shielding UV radiation. Additionally, this strategy provides a common and facile route to fabricate functional composite hydrogels via photo‐induced polymerization.     

Electroresponsive and spinnable hydrogels from xanthan gum and gelatin enhanced by Fe3+ ions coordination

Polyelectrolyte hydrogels with spinnability and electroresponsive were prepared from xanthan gum (XG) and gelatin. Oscillatory rheological measurements were utilized to explore mechanical properties and thermal stability of the resultant XG-Gelatin5 hydrogels. The XG-Gelatin5 hydrogels possessed higher strength and larger critical strain than these of the XG hydrogels, demonstrating existence of synergistic interactions. The XG-Gelatin5 hydrogels were stable in temperature range of 20–60°C, and gradually release drug with controlled manner in neutral and acid medium at 37°C. The self-recoverable and thixotropic XG-Gelatin5 hydrogels were extruded to form hydrogel fibers, and the dried hydrogel fibers rapidly bend towards cathode under applied voltage. Long hydrogel fibers were harvested with enhancement by Fe³⁺ ions, and were weaved and braided to obtain hydrogel fiber constructs. The XG-Gelatin5 hydrogel fibers with electroresponsive and controlled drug release possess potential applications in biomaterials, tissue engineering, and drug carrier fields.     

Preparation and properties of a novel thermosensitive <Emphasis Type="Italic">N</Emphasis>-trimethyl chitosan hydrogel

A novel injectable thermosensitive hydrogel system composed of N-trimethyl chitosan chloride (TMC) and β-glycerophosphate (β-GP), coded as TMC/β-GP, was designed. The morphology and rheological behavior of hydrogels were characterized by scanning electron microscopy and rheometer, respectively. Their swelling properties were carefully studied. The results revealed that the TMC/β-GP system was liquid with low viscosity at low temperature, which allowed it to be an ideal injectable material for biomedical applications. It was interesting that the system kept in liquid status for a long time near 4 °C and transformed rapidly to gel status within 1 min upon heating to 37 °C. The hydrogel could be dissolved at acid pH, while it absorbed water at neutral and basic conditions. The release of BSA from TMC/β-GP gels was slow at neutral pH. The TMC/β-GP hydrogel is a promising vehicle for the drug release, tissue repairing and regeneration.     

Thermo- and pH-responsive HPC-g-AA/AA hydrogels for controlled drug delivery applications

This paper describes smart hydrogels composed of pH-sensitive poly(acrylic acid) (PAA) and biodegradable temperature-sensitive hydroxypropylcellulose-g-acrylic acid (HPC-g-AA) for controlled drug delivery applications. In a pH-responsive manner, the hydrogels with the higher HPC-g-AA content resulted in the lower equilibrium swelling. Although temperature had little influence on the swelling of the hydrogels, optical transmittance of the hydrogels was changed as a function of temperature, which reflecting that the HPC parts of hydrogel became hydrophobic at temperature above the lower critical solution temperature (LCST). Scanning electron microscopic analysis revealed that the pore size and the morphology of the hydrogels could be controlled by changing the composition of AA and the crosslinking density. Using BSA as a model drug, in vitro drug release experiment was carried out in artificial gastric juice (pH = 1.2) for the first 2 h and then in artificial intestinal liquid (pH = 6.8) for the subsequent 6 h. The release profiles indicated that both HPC-g-AA and AA contents played important roles in the drug release behaviors. The temperature- and pH-responsive HPC-g-AA/AA hydrogels might be exploited for wide applications in controlled drug delivery.     

A Dual Physical Cross-Linking Strategy to Construct Tough Hydrogels with High Strength,Excellent Fatigue Resistance,and Stretching-Induced Strengthening Effect

Hydrogels with excellent stiffness, toughness, anti-fatigue, and self-recovery properties are regarded as promising water-containing materials. In this work, a dual physically cross-linked (DPC) sodium alginate (SA)/poly[acrylamide (AAm)-acrylic acid (AAc)-octadecyl methacrylate (OMA)]-Fe³⁺ hydrogel is reported, which is constructed by hydrophobic association (HA) and ionic coordination (IC). The optimal DPC hydrogel demonstrates excellent mechanical performance: tensile modulus of 0.65 MPa, tensile strength of 3.31 MPa, elongation at break of 1547%, and toughness of 27.8 MJ m^–3. SA/P(AAm-AAc-OMA)-Fe³⁺ DPC hydrogels also exhibit prominent anti-fatigue and self-recovery performance (99.1–109.7% modulus recovery and 90.4–108.9% dissipated energy recovery after resting for 5 min without additional stimuli at ambient temperature) through the reconstruction of reversible physical cross-linking. Some of the SA/P(AAm-AAc-OMA)-Fe³⁺ DPC hydrogels even exhibit a stretching-induced strengthening effect, which is similar to the performance of muscle—“the more training, the more strength.” Hence, the combination of HA and IC will provide an effective approach to design DPC hydrogels with desirable mechanical performances and a longer service life for wider applications of soft materials.     

Preparation of cellulose-based conductive hydrogels with ionic liquid

Conductive hydrogel composed of microcrystalline cellulose (MCC) and polypyrrole (PPy) was prepared in ionic liquid; and the resulting hydrogel was characterized with FT-IR, SEM, XRD and TGA. By doping with TsONa, the MCC/PPy composite hydrogels showed relatively high electrical conductivity, up to 7.83 × 10⁻³ S/cm, measured using a four-probe method. The swelling kinetics of the composite hydrogels indicated that the swelling process was mainly influenced by the cellulose content; and the equilibrium swelling ratio decreased as the increasing of MCC content in the hydrogels. In addition, the MCC/PPy composite hydrogels exhibited significantly enhanced mechanical property in contrast to MCC hydrogel.