PURPOSE: To evaluate the compatibility of poloxamer hydrogel as a material for the injectable intraocular lens in in vivo and in vitro model. METHODS: We determined the appropriate concentration of poloxamer hydrogel for injection through the examination of transparency and gelling temperature of this material and assess the technique of refilling the lens capsule and the postoperative findings. RESULTS: Poloxamer hydrogel showed excellent transparency compared with balanced salt solution(BSS) in air vinyl and 20% was identified as an appropriate concentration for direct lens refilling material. In vivo study, we injected poloxamer into the capsular bag after performing endocapsular phacoemulsification through the small anterior capsulotomy site. At 3 months follow up, we confirmed the excellent transparency and biocompatibility of poloxamer hydrogel. CONCLUSIONS: Poloxamer hydrogel was identified as an appropriate material for direct lens refilling material.
Follow-Up Studies ; Hydrogel* ; Lenses, Intraocular* ; Phacoemulsification ; Poloxamer ; Polymers*

OBJECTIVETo prepare and evaluate the injectable temperature responsive in situ gel for sustained release of Glabrous Sarcandra Herb extract in vitro.

METHODThe novel temperature responsive poloxamer 407 was used as the carrier material of Glabrous Sarcandra Herb extract sustained release injection. The release of Glabrous Sarcandra Herb extract from poloxamer 407 based in situ gel in the phosphate buffer (pH 7. 6) was studied at 37 degrees C under agitation. HPLC method was used for the determination of Glabrous Sarcandra Herb extract.

RESULTThe best prescription was composed of by 16% P-407, 6% P-188, 0.2% HPMC, 0.5% benzil alcohol and 4% (g mL(-1)) Glabrous Sarcandra Herb extract. The optimal gelation temperature was around 33 degrees C. The data of release in vitro were analyzed according to the theoretical model of Korsmeyer-Peppas.

CONCLUSIONThe preparation method of the injectable thermosensitive in situ gel of Glabrous Sarcandra Herb extract is appropriate. The release in vitro can reach the expecting request.

Objective: To observe the effect of poloxamer 188 (P188) on megakaryocyte cultivation and induction from cord blood mononuclear cells in order to obtain more megakaryocyte progenitor cells (MPC). Methods: The cord blood mononuclear cells were isolated and inoculated in cell culture bag or cell culture flask respectively. The WIGGENS shaker and cell culture bags were used to mimick WAVE Bioreactor for three-dimensional (3D) cell culture, and the P188 was added to induction medium, The cells were detected for morphology, surface marker, viability, and number on day 14. Results: In the two-dimensional (2D) culture, CD41(+), CD41(+)/CD61(+), CD61(+) megakaryocytic numbers increased significantly after adding P188 (all P<0.01). And in the 3D culture of adding P188, the cell volume became larger and the nuclear shape was irregular, the cytoplasm appeared magenta granules, and the megakaryocyte cells became more mature. By 3D culture, the expression of CD41/CD61 was (36.30±1.27)% vs (23.95±1.34)%, hence the differentiation for MPC was significantly higher than that in the 2D group (P<0.01). Furthermore, adding P188 in 3D culture resulted in highest differentiation efficiency for MPC [(59.45±1.20)%]. There were no significantly differences in terms of cell viability and cell number among 3D culture containing P188, 2D and 3D culture groups (all P>0.05). Conclusion: 3D culture was beneficial for the differentiation of MPC, but the cell viability was lower than 2D group; However, the satisfied cell growth and better induction efficiency were obtained by adding of P188, which might provide a new method of megakaryocytes production for clinical application.
Bioreactors ; Cell Differentiation ; Cells, Cultured ; Fetal Blood ; Megakaryocytes ; Poloxamer

This study was designed to investigate the optimal poloxamer concentration in the mixed solution of recombinant human epidermal growth factor and poloxamer which can be effective in the wound healing process. Two full-thickness excisions were made on the back of the experimental animals. Recombinant human epidermal growth factors(RhEGF) containing different poloxamer concentrations were applied twice a day and the rates of wound closure were measured every day for 14 days. On the 7th and 14th postoperative day, the histological analysis for epithelization and granulation were performed using computerized imaging analysis system after Masson's trichrome stains. The healing times 50% were significantly reduced in the RhEGF containing 0, 3 and 6% poloxamer treated groups as compared with both the non treated control and vehicle control group(p < 0.05). However, there were no statistical differences in the healing times 50% in the RhEGF containing 10, 15 and 20% poloxamer treated groups as compared with both the non treated control and vehicle control group. Histological examinations revealed that epithelization and granulation were increased significantly in the RhEGF containing 0, 3 and 6% poloxamer treated groups as compared with control group and vehicle control group at the 7th day after operation(p < 0.05). In conclusion, these findings suggest that RhEGF may enhance the epithelial wound healing process through stimulating cell proliferation. The concentration of 0, 3 and 6% of poloxamers can be applied to stabilize and enhance the wound healing effect of RhEGF for clinical application.
Animals ; Cell Proliferation ; Coloring Agents ; Epidermal Growth Factor* ; Humans* ; Poloxamer* ; Rats* ; Wound Healing* ; Wounds and Injuries*

PURPOSE: The occurrence of post-surgical adhesion is still a major cause of postoperative morbidity due to the lack of satisfactory treatment or prophylaxis. Several adhesion barriers have been developed in the form of solutions or membrane in an attempt to solve these problems. However both types of tissue barriers have some limitations in their practical applications. In order to overcome these problems, a temperature-sensitive Poloxamer/Alginate/CaCl2 mixture was prepared as an adhesion barrier. With this material, toxicity, inflammation and the adhesion prevention effect was evaluated in an animal model. METHODS: The sol-gel transition behavior was measured using a viscometer. An in vitro gel stability test and an in vivo degradation test was performed. The anti-adhesion effect was evaluated using a cecal-abdominal wall abrasion model. The denuded cecum was coated with Poloxamer/ Alginate/CaCl2 mixture, GUARDIX-SL (positive control group) or neither (negative control group) and apposed to the abdominal wall (each n=14). One week after surgery, the level of adhesion was graded from zero to three using a whole-number system. RESULTS: The LCST of the poloxamer/sodium alginate mixture was 25 degrees C. The gel stability of Poloxamer was improved by adding mild cross-linked sodium Alginate/CaCl2 mixture. The adhesion grade and area were significantly lower in the experimental group than in the control. CONCLUSION: The anti-adhesive effect of the Poloxamer/Alginate/CaCl2 mixture was comparable to the previously- developed solution type barrier and all the materials had degraded within 21 days. From these results, Poloxamer/ Alginate/CaCl2 mixture is a good candidate for use as a coatable or injectable tissue adhesion barrier.
Abdominal Wall ; Animals ; Cecum ; Inflammation ; Membranes ; Models, Animal* ; Poloxamer ; Rats* ; Sodium ; Tissue Adhesions

PURPOSE: This study was designed to induce irreVersible gel formation of poloxamer, the thermosensitive polymer hydrogel, by using photoinitiator and UV irradiation, and to verify the biocompatibility and usability of poloxamer as an injectable intraocular lens material through long-term observation in vivo. METHODS: Endocapsular phacoemulsification of lens was performed in rabbits and 25% poloxamer mixed with various concentrations of photoinitiator was injected into the capsular bag through a small capsulorhexis site. Then, the whole eye was irradiated with UV light for 5 minutes. The irreversibility and transparency of the post-operative poloxamer and the effects on the conjunctiva, cornea, iris, vitreous humor and retina were observed. RESULTS: As the results of this experiment using poloxamer 25% and photoinitiator 0.01%, the poloxamer remained transparent in the lens capsule for more than six months after the operation. No inflammatory response or toxicity was observed on the conjunctiva, cornea, iris, vitreous humor or retina. CONCLUSIONS: This study demonstrated the possibility of poloxamer as a new material for the injectable intraocular lens. Further study, however, is necessary.
Capsulorhexis ; Conjunctiva ; Cornea ; Hydrogel ; Iris ; Lenses, Intraocular* ; Phacoemulsification ; Poloxamer ; Polymers ; Rabbits* ; Retina ; Ultraviolet Rays ; Vitreous Body

Drug Carriers ; Drug Combinations ; Drugs, Chinese Herbal ; administration & dosage ; Poloxamer ; Polyethylene Glycols ; Solubility ; Technology, Pharmaceutical ; methods

The objectives of this study are to prepare resveratrol loaded mixed micelles composed of poloxamer 403 and poloxamer 407, and optimize the formulation in order to achieve higher drug solubility and sustained drug release. Firstly, a thin-film hydration method was utilized to prepare the micelles. By using drug-loading, encapsulation yield and particle size of the micelles as criteria, influence of three variables, namely poloxamer 407 mass fraction, amount of water and feeding of resveratrol, on the quality of the micelles was optimized with a central composite design method. Steady fluorescence measurement was carried out to evaluate the critical micelle concentration of the carriers. Micelle stability upon dilution with simulated gastric fluid and simulated intestinal fluid was investigated. The in vitro release of resveratrol from the mixed micelles was monitored by dialysis method. It was observed that the particle size of the optimized micelle formulation was 24 nm, with drug-loading 11.78%, and encapsulation yield 82.51%. The mixed micelles increased the solubility of resveratrol for about 197 times. Moreover, the mixed micelles had a low critical micelle concentration of 0.05 mg · mL(-1) in water and no apparent changes in particle size and drug content were observed upon micelles dilution, indicating improved kinetic stability. Resveratrol was released from the micelles in a controlled manner for over 20 h, and the release process can be well described by Higuchi equation. Therefore, resveratrol-loaded poloxamer 403/407 mixed micelles could improve the solubility of resveratrol significantly and sustained drug release behavior can be achieved.
Drug Carriers ; chemistry ; Fluorescence ; Kinetics ; Micelles ; Particle Size ; Poloxamer ; chemistry ; Solubility ; Stilbenes ; chemistry ; Water

PURPOSE: The purpose of this study was to evaluate the effect of two sustained release systems (Pluronic F-127 gel and Fibrin glue) on the diffusion of dexamethasone across the human sclera. METHODS: Scleral sections excised from moist-chamber-stored human globes were mounted in a perfusion chamber that can create transscleral pressure. In the sustained release study, sample (100 muL) of 3H-dexamethasone in Pluronic F-127 gel or Fibrin glue was added to the episcleral side of the tissue, while BSS plusR was perfused across the uveal side at an transscleral pressure of 15 mmHg. Perfusate fractions were collected and measured using scintillation spectrometry and scleral permeability was calculated. RESULTS: The apparent permeability constants of the human sclera to 3H-dexamethasone in BSS plus(R) (the control value), Pluronic F-127 gel, and Fibrin glue were 1.15+/-0.11x10(-5) cm/s (n=5), 1.49+/-0.33x10-6 cm/s (n=5), and 7.32+/-0.98x10(-6) cm/s (n=7), respectively. The permeability values of Pluronic F-127 gel and Fibrin glue were relatively lower than the control value. Pluronic F-127 gel and Fibrin glue showed a uniform sustained release characteristic during a 24-hour period. The cumulative release rates of dexamethasone through the human sclera from BSS plus(R) (the control value), Pluronic F-127 gel, and Fibrin glue were 84.0+/-1.5% (n=5), 29.3+/-5.8% (n=5), and 61.5+/-5.9% (n=4) at 20 hours, respectively. There were significant differences in the human scleral permeability constants and cumulative release rates among the three vehicles (p<0.0001). CONCLUSIONS: Pluronic F-127 gel and Fibrin glue provided a slow, uniform sustained release during a 24- hour period. This study established a strong possibility of the new transscleral drug delivery in vitro using the sustained release systems of Pluronic F-127 gel and Fibrin glue. This may be a good experimental tool in the future development of a practical drug delivery system across the sclera for the treatment of a variety of chorioretinal disorders.
Dexamethasone ; Diffusion ; Drug Delivery Systems ; Fibrin Tissue Adhesive* ; Fibrin* ; Humans ; Perfusion ; Permeability ; Poloxamer* ; Sclera ; Spectrum Analysis

BACKGROUND: Lipid-emulsion propofol (LP) has cardioprotective effects against ischemia-reperfusion injury, but it has lipid-related side effects. Microemulsion propofol (MP) is a lipid-free propofol emulsified with 10% purified poloxamer 188 (PP188). PP188 is a nonionic surfactant and has cardioprotective effects. However, some reports have suggested that reduced cardioprotective effects were observed when the cardioprotective agents were used in combination even though each cardioprotective agent has cardioprotective effects. The aims of this study were to examine and compare the cardioprotective effects of MP and LP. METHODS: 50 isolated rat hearts were perfused with modified Kreb's solution. They were divided into 4 groups and underwent 30 minutes of ischemia and 60 minutes of reperfusion. Control group: ischemia-reperfusion was performed without treatment. LP, MP and PP groups: LP, MP and PP188 were infused during the pre-ischemic and reperfusion period, respectively. Hemodynamic parameters and coronary effluent flow rate (CEFR) were measured. Infarct size was determined using triphenyl-tetrazolium staining. RESULTS: In the MP group, systolic pressure was maintained near baseline, the systolic pressure was higher than that in the other groups and HR was lower than that in the other groups during reperfusion. Diastolic pressure was transiently increased in the PP group after treatment and at 5 minutes after reperfusion compared with that in the control group and in the the LP group. There were no differences in dP/dtmax and CEFR between groups. Infarct size in the LP, MP and PP groups was smaller than that in the control group, but there were no significant differences between these three groups. CONCLUSIONS: MP has cardioprotective effects similar to those of LP. MP can be used for cardiac anesthesia in cases with ischemia-reperfusion injury to avoid the lipid-related side effects of LP.
Anesthesia ; Animals ; Blood Pressure ; Cardiotonic Agents ; Heart ; Hemodynamics ; Ischemia ; Poloxamer ; Propofol ; Rats ; Reperfusion ; Reperfusion Injury