Articular osteocartilage injury caused by trauma or bone disease is very common in clinical practices,the proportion of cartilage defects reached 40.31%. As the low self healing abilities of articular cartilage, the technology of tissue engineering becomes a new method to treat articular cartilage injuries with regenerative medicine. Scaffolds can be divided into preformed and hydrogel scaffolds according to properties. The traditional graft of pre-formed scaffold will bring the secondary injury to the cartilage around the defect, and the loose graft intergration with the defect surface is still a problem. Repairing irregular articular cartilage defects with ideal biomimic materials on the basis of avoiding secondary damage will become a main issue. The method of minimally invasive injecting, biomimics, and in situ remodeling brings hope to articular cartilage repairing. Below is a summary of the international and domestics reference data of recent years on collagen hydrogel in cartilage tissue engineering.
Collagen ; Humans ; Hydrogel, Polyethylene Glycol Dimethacrylate ; Tissue Engineering ; methods

The biocompatible hydrogel was fabricated under suitable conditions with natural dextran and polyethylene glycol (PEG) as the reaction materials. The oligomer (Dex-AI) was firstly synthesized with dextran and allylisocyanate (AI). This Dex-AI was then reacted with poly (ethyleneglycoldiacrylate) (PEGDA) under the mass ratio of 4∶6 to get hydrogel (DP) with the maximum water absorption of 810%. This hydrogel was grafted onto the surface of medical catheter via diphenyl ketone treatment under ultraviolet (UV) initiator. The surface contact angle became lower from (97 ± 6.1)° to (25 ± 4.2)° after the catheter surface was grafted with hydrogel DP, which suggests that the catheter possesses super hydrophilicity with hydrogel grafting. The evaluation after they were implanted into ICR rats subcutaneously verified that this catheter had less serious inflammation and possessed better histocompatibility comparing with the untreated medical catheter. Therefore, it could be concluded that hydrogel grafting is a good technology for patients to reduce inflammation due to catheter implantation, esp. for the case of retention in body for a relative long time.
Allyl Compounds ; Animals ; Biocompatible Materials ; Catheters ; Dextrans ; Hydrogel, Polyethylene Glycol Dimethacrylate ; Hydrogels ; Hydrophobic and Hydrophilic Interactions ; Isocyanates ; Polyethylene Glycols ; Rats ; Water

The neotype of amphiphilic oligopeptide (C16 H31 O-AAAGGGGDDIKVAV) was synthesized. The framework of three-dimensional and porous hydrogel self-assembly from the amphiphilic oligopeptide on different conditions was explored. The peptide, whose molecular weight (MW) and purity were detected by Mass Spectrometer (MS) and High Performance Liquid Chromatograph (HPLC) respectively, was synthesized in solid phase methods. Peptide was dissolved in 0.1 mol/L Sodium Hydroxide (NaOH) solution. 200 microl of 10, 2, 1, 0.5 wt% peptide solutions, which were prepared respectively, were added into the same volume of DMEM/F12, or placed into the vapor of 10 mol/L Hydrochloric acid (HCl), or were used to coat in the surface of coverslip and set into the baking oven at 37 degrees C. The self-assembly hydrogel was examined with transmission electron microscope (TEM) and scanning electron microscope (SEM). MS showed that peptide MW was 1438.31. HPLC testified that the peptide purity was 96%. The peptide solution was self-supported into hydrogel triggered with DMEM/F12 in few seconds, or the thin hydrogel after two hours in the vapor of 10 mol/L HCl, or not hydrogel in the baking oven at 37 degrees C. SEM showed that the hydrogel self-assembly from 10 wt% peptide solution was composed of nanofibers that ranked in layers where there were thick voids. TEM showed that the hydrogel self-assembly from 2, 1, 0.5 wt% peptide solution comprised woven network nanofibers, that the nanofibers of hydrogel self-supported from 1 wt% peptide solution varied from 3 to 6 nm in diameter and 100 nm to 1.5 um in length, that the nanofibers of hydrogel self-supported from 2 wt% peptide solution ranked closely, and there were big voids within the thin nanofibers of hydrogel self-supported from 0.5 wt% peptide solution. The amphiphilic oligopeptide was synthesized and self-organized successfully into porous hydrogel characterized as "intelligent" tissue engineering scaffolds containing the bioactive ligand, which was triggered by DMEM/F12.
Biocompatible Materials ; Hydrogel, Polyethylene Glycol Dimethacrylate ; chemical synthesis ; chemistry ; Peptides ; chemical synthesis ; chemistry ; Porosity ; Tissue Engineering ; methods ; Tissue Scaffolds ; chemistry

Poly (hydroxyethyl methacrylate) (PHEMA) hydrogel for intraocular lens (IOL) materials was synthesized by solution polymerization using 2-hydroxyethyl methacrylate (HEMA) as raw material, ammonium persulfate and sodium pyrosulfite (KPS/SMBS) as catalyst, and trietyleneglycole dimethacrylate (TEGDMA) as cross-linking additive. Effects of reaction time, temperature, dosage of catalyst and cross-linking additive on mechanical strength and the equilibrium water content (EWC) of the PHEMA hydrogel were systematically investigated and their structure and optical property were also characterized. The experimental results showed that the optimum conditions for preparing PHEMA hydrogel are: catalyst 0.5 wt%, cross-linking additive 1.0 wt%, reaction temperature 40 degrees C, reaction time 36 h. Under the optimum conditions, the tensile strength of PHEMA hydrogel prepared is as high as 0.57 MPa, hardness of Shore A is 23.0, EWC is over 40%, and light transmittance is over 97%.
Biocompatible Materials ; chemistry ; Humans ; Hydrogel, Polyethylene Glycol Dimethacrylate ; chemistry ; Lenses, Intraocular ; Polyhydroxyethyl Methacrylate ; chemical synthesis ; chemistry ; Tensile Strength

The properties of biomedical intelligent polymer materials can be changed obviously when there is a little physical or chemical change in external condition. They are in the forms of solids, solutions and polymers on the surface of carrier, including aqueous solution of hydrophilic polymers, cross-linking hydrophilic polymers (i.e. hydrogels) and the polymers on the surface of carrier. In this paper are reviewed the progress in researches and the application of biomedical intelligent polymer materials.
Biocompatible Materials ; chemistry ; Biotechnology ; Chemical Phenomena ; Chemistry, Physical ; Hydrogel, Polyethylene Glycol Dimethacrylate ; chemistry ; Polymers ; chemistry ; Surface Properties

In this study, using ethylene carbonate and ethanolamine, we synthesized a novel diol chain-extender, bis-hydroxylethyl carbomate (EC-AE), which contains carbomate structure. The polyurethanes, PUA25 and PUB25, with different extenders, EC-AE and BDO, were synthesized by one-step polymerization, respectively. Their structures were characterized by using FT-IR and DSC. The results indicated that the microphase separation degree of PUA25 was less than that of PUB25, in other words, the amount of hydrogen bonding between hard segments and soft segments in PUA25 was superior to that in PUB25. And the formation of physically crosslinked hydrogels prepared by PUA25 and PUB25 were studied in detail. It was found that only PUA25 can form hydrogel in situ from solution state by cooling. And this kind of hydrogels showed the transition cycle of "gel-sol-gel" under "cooling-heating-cooling" thermal cycles, respectively. The results suggested that the physically crosslinked polyurethane hydrogels were easily possessed in high degree of phase mixing.
Biocompatible Materials ; Cross-Linking Reagents ; chemistry ; Hydrogel, Polyethylene Glycol Dimethacrylate ; chemical synthesis ; chemistry ; Polyurethanes ; chemical synthesis ; chemistry

OBJECTIVETo observe whether injectable hydrogel implantation could prevent adverse cardiac remodeling and preserve cardiac function in rabbits with myocardial infarction (MI).

METHODSA novel injectable hydrogel, the copolymer MPM/alpha-CD, which self-assembled between alpha-cyclodextrin and methoxy polyethylene glycol-poly (caprolactone)-(dodecanedioic acid)-poly (caprolactone)-methoxypolyethylene glycol triblock polymer, was synthesized by chemical crosslinking and characterized by biocompatibility and biodegradability. Experimental MI was induced in male rabbits by coronary artery ligation. The MI rabbits were randomly divided into hydrogel group (200 microl MPM/alpha-CD were injected into the infarcted myocardium 7 days after MI) and control group (equal volume phosphate buffered saline myocardial injection, n = 8 each). Four weeks after MPM/alpha-CD implantation, echocardiography, histochemistry and immunohistochemistry were performed.

RESULTSLeft ventricle ejection fraction was significantly improved in the hydrogel-treated group (56.1% +/- 8.4%) than that in the control group (37.3% +/- 6.4%, P < 0.05). Histological analysis indicated that hydrogel degraded 4 weeks after hydrogel injection, and prevented scar expansion and wall thinning [(3.08 +/- 0.32) mm vs. (2.18 +/- 0.46) mm in control group, P < 0.05]. Neovasculature formation was similar between the hydrogel group [(100.8 +/- 2.4)/mm(2)] and the control [(98.5 +/- 2.9)/mm(2), P > 0.05].

CONCLUSIONMPM/alpha-CD could serve as an excellent injectable biomaterial for improves cardiac function and attenuating scar expansion and left ventricular dilation in MI rabbits.

Animals ; Heart Ventricles ; Hydrogel, Polyethylene Glycol Dimethacrylate ; administration & dosage ; pharmacology ; therapeutic use ; Male ; Myocardial Infarction ; physiopathology ; therapy ; Rabbits ; Ventricular Remodeling ; drug effects

Starting from the form of red blood cells and the hematocrit (Hct, about 45 vol% of whole blood), we tried to prepare a kind of microspheres suspension to imitate non-Newtonian fluid property of whole blood, exploring its potentiality to be applied in blood viscosity quality control substance. In our study, we produced Ca-alginate hydrogel microspheres using emulsion polymerization, then we suspended the microspheres in 0.9 wt% NaCl solution to obtain a kind of liquid sample with the microspheres taking 45% volume. Then we used two types of viscometers to measure and analyse the changes of sample viscosity at different shear rate. We observed the forms of Ca-alginate hydrogel microspheres with microscope, and found them to be relatively complete, and their diameters to be normally distributed. Diameters of about 90% of the microspheres were distributed in a range from 6 to 22 micron. The samples were examined with viscometer FASCO-3010 and LG-R-80c respectively, both of which have shown a shear-thinning effect. After 5-week stability test, the CV of viscosity results corresponding to the two instruments were 7.3% to 13.8% and 8.9% to 14.2%, respectively. Although some differences existed among the results under the same shear rate, the general variation trends of the corresponding results were consistent, so the sample had the potentiality to be widely used in calibrating a different type of blood viscometer.
Alginates ; chemistry ; Blood Viscosity ; Calcium ; chemistry ; Glucuronic Acid ; chemistry ; Hexuronic Acids ; chemistry ; Humans ; Hydrogel, Polyethylene Glycol Dimethacrylate ; chemistry ; Microspheres ; Plasma Substitutes ; chemistry ; Rheology ; instrumentation ; Suspensions ; chemistry

BACKGROUNDWound dressings are divided into traditional and new types. The new dressings are thought to accelerate wound healing. The purpose of this study was to supplement the scanty data on the absorbency of the new dressings and their effects on evaporation from the burn surface.

METHODSThe water absorption rate of four dressings (carbon fiber dressing, hydrogel dressing, silver nanoparticle dressing, and vaseline gauze) were measured by the immersion-weight gain method. A total of 120 inpatients with 10% superficial partial-thickness burn wounds were randomly assigned to four groups, each with 30 participants. Carbon fiber dressing, hydrogel dressing, and silver nanoparticle dressing were used in groups A, B, and C as the primary dressing, and traditional vaseline gauze was used in group D as the control. Multi-spot evaporation from normal skin and naked wound, and from wounds covered with each of the four dressings was measured post-burn on days 1, 3, 5, and 7 by an EP-I evaporimeter under conditions of 21 degrees C - 22 degrees C ambient temperature and 74% - 78% humidity.

RESULTSThe absorption rates of the four dressings were 988% with carbon fiber dressing, 96% with silver nanoparticle, 41% with vaseline gauze, and 6% with hydrogel. Evaporation from the naked burn wounds was about 1/3 higher than from normal skin (P < 0.01). Compared with wounds without applied dressing, evaporation from dressed wounds decreased and was time-dependent (P < 0.01). The evaporation of wounds with carbon fiber dressing was the lowest ((13.40 +/- 2.82) mlxh(-1)xm(-2), P < 0.01) on day 1 post-burn, compared with the other groups.

CONCLUSIONAll four dressings have water retention capacity while carbon fiber dressing has the highest absorption rate and shows the best containment and evaporation from the burn wound.

Adult ; Bandages ; Burns ; therapy ; Carbon ; therapeutic use ; Female ; Humans ; Hydrogel, Polyethylene Glycol Dimethacrylate ; therapeutic use ; Male ; Middle Aged ; Nanoparticles ; Petrolatum ; therapeutic use ; Silver ; therapeutic use ; Volatilization ; Wound Healing

OBJECTIVETo observe the effect of the chitosan thermosensitive hydrogel loading recombinant human bone morphogenetic protein-2 (rhBMP-2) on repairing periodontal defects.

METHODSTo prepare artificial furcation defects model in the posterior area in 3 healthy male dogs, and then to inject chitosan thermosensitive hydrogel loading of rhBMP-2 after fast suturing tissue flap. The groups filled with nothing or filled only with chitosan thermosensitive hydrogel were the controls. The dogs were sacrificed after 5 weeks and the periodontal regeneration was observed histologically.

RESULTSThe histological observation showed that the chitosan thermosensitive hydrogel loading rhBMP-2 group achieved apparent periodontal tissue regeneration occupying the majority of the defects and the control groups got only a small amount of periodontal tissue regeneration.

CONCLUSIONThe chitosan thermosensitive hydrogel loading rhBMP-2 can effectively promote the periodontal tissue regeneration, while simplifying the surgical operation. It might be a potential means for periodontal regeneration.

Animals ; Bone Morphogenetic Protein 2 ; Bone Morphogenetic Proteins ; Chitosan ; Dogs ; Humans ; Hydrogel, Polyethylene Glycol Dimethacrylate ; Male ; Recombinant Proteins ; Regeneration ; Transforming Growth Factor beta