Well-defined amphiphilic tri-block copolymer PVP-b-PMMA-b-PVP was prepared for the first time via successive reversible addition fragmentation chain transfer(RAFT) polymerization using carboxyl-terminated trithiocar...Well-defined amphiphilic tri-block copolymer PVP-b-PMMA-b-PVP was prepared for the first time via successive reversible addition fragmentation chain transfer(RAFT) polymerization using carboxyl-terminated trithiocarbonate as the RAFT agent.The structure of the copolymer was characterized using FTIR,GPC and ~1H NMR.The block copolymer could be directly blended with polyethersulfone(PES) as a macromolecule additive using N-methyl-2-pyrrolidone(NMP) as the solvent to prepare membranes. The water contact angles for the modified membranes decreased obviously,and therefore,the protein adsorption amount on the membrane surface decreased.展开更多
The dual-bath coagulation method was used for the preparation of PES membrane in this experiment. The main intent of this stndy was to assess the efforts of gelation conditions on the structures and properties. The d...The dual-bath coagulation method was used for the preparation of PES membrane in this experiment. The main intent of this stndy was to assess the efforts of gelation conditions on the structures and properties. The dense top layer as well as porous supporting layer can be made by duel-bath coagulation method simultaneous- ly. Different internal quench medium obtained different membrane with different structures. With the increase in time in the first coagulation bath, pure water flux decreased and the clearance rates of urea and creatinine both first increased then decreased and increased slightly in the end. With the temperature of the second coagtdation bath increasing, pure water flux increases and the clearance rates of urea and creatinine first increases then de- creases and increases a little at last. Higher DMSO concentration (wt/wt) in the second coagulation bath results in the increase of pure water flux and the decrease of urea & creatinine clearance rates.展开更多
Objective: To observe the safety and efficacy of polyethersulfone membrane dialyzer used by chronic renal failure patients in clinical maintenance hemodialysis (MHD). Methods: From January to February 2009, 36 pat...Objective: To observe the safety and efficacy of polyethersulfone membrane dialyzer used by chronic renal failure patients in clinical maintenance hemodialysis (MHD). Methods: From January to February 2009, 36 patients were recruited from Xinhua Hospital Affiliated to Shanghai Jiao Tong University School of Medicine. The experiment was approved by the ethnical committee of Xinhua Hospital and under permissions fronl patients. All the patients were randomized into polyethersulfone group (PES, n=18) and polysulfone group (PS, n=18). Hemodialysis was given by using Fresenius 4008S capacity-controlled dialyser and ultra-purified bicarbonate dialysate, more than 3.5 h each time, three times per-week, followed by heparin anticoagulation for a week, three times totally. Changes in blood urea nitrogen (BUN), serum creatinine (Set), phosphate (p2+), hemoglobin and albumin levels were determined for the efficacy and safety evahlation. Results: The serum BUN, Set and p2+ concentrations significantly reduced after hemodialysis with different dialyzers, and the decrease amplitude of two groups was equivalent(P〉0.05). The clearance rate of the serum BUN and Scr had no significant difference among two groups(P〉O.05). The clearance rate (ml/min) of the sermn P^2+ was 144.57 ±27.83 v.s. 117.15 ±22.77 in two groups. The clearance rate of the serum p^2+ in PES group was more than that in PS group, and the difference was significant between two groups (P=0.0001). It was indicated that PES and PS membrane could efficiently eliminate serum mieromolecule solute in MHD patients, so PES membrane excelled PS membrane in eliminating serum p2+. The hemodialysis safety index, for example serum hemoglobin, albumin and blood pressure, had no significant difference between the two groups before and after hemodialysis (P〉0.05). Conclusion: The efficacy and safety of the PES hollow fiber membrane dialyzer is equivalent to that of the imported PS membrane dialyzer in hemodialysis for MHD patients. The PES membrane excels PS membrane in eliminating sermn p^2+.展开更多
Hydrophilic modification is a promising method to inhibit fouling formation on ultrafiltration membrane.In this work,different mass concentrations(1%–16%)of hydrophilic polyvinylpyrrolidone were incorporated into pol...Hydrophilic modification is a promising method to inhibit fouling formation on ultrafiltration membrane.In this work,different mass concentrations(1%–16%)of hydrophilic polyvinylpyrrolidone were incorporated into polyethersulfone(PES)membranes fabricated by none-solvent induced phase separation.Then,polydopamine(PDA)coating on the surface of prepared membrane was carried out at pH 8.5.The morphology and structure,surface hydrophilicity,permeation flux,BSA rejection,antifouling and stability performances of PES and PDA/PES modified membranes were investigated in detail.The results indicated that PDA was successfully attached onto the membranes.Membrane hydrophilicity was evaluated by water contact angle measurement.The contact angles of modified membranes reduced remarkably,suggesting that the membrane hydrophilicities were significantly increased.The results of filtration tests,which were done by dead-end filtration of bovine serum albumin solution,showed that the properties of permeability and fouling resistance were obviously improved by PDA modification.When polyvinylpyrrolidone mass content reached 10%,flux recovery ratio of modified membrane was up to91.23%,and its BSA rejection were over 70%.The results of stability tests showed that the modified membranes had good mechanical stability and chemical stability.This facile fabrication procedure and outstanding performances suggested that the modified membranes had a potential in treating fouling.展开更多
The transport performances of carbon dioxide and methane were studied in polyethersulfone, polyethersulfone/polyeterurethane(PES–ETPU) and polyethersulfone/polyestherurethane(PES–ESPU) blend membranes separately wit...The transport performances of carbon dioxide and methane were studied in polyethersulfone, polyethersulfone/polyeterurethane(PES–ETPU) and polyethersulfone/polyestherurethane(PES–ESPU) blend membranes separately with different compositions. The variations in the structural characteristics of PES membrane after incorporation of ESPU and ETPU were investigated by different techniques. Additionally, the effect of pressure and composition on the permeance of CO_2, CH_4 and ideal selectivity of CO_2/CH_4 were checked on the membranes.The results revealed that the morphology of the blend membranes was affected by two opposite factors: thermodynamic enhancement and kinetic hindrance. The membranes with denser sponge layers were formed at lower ratio of PU/PES, while more porous structure with enlarged macrovoids membranes were observed at higher PU content. The results indicated that adding PU to PES membrane, caused permeance improvement of the gases with nearly no change and/or reduction in ideal selectivity of CO_2/CH_4. Moreover, PES–ETPU membranes showed higher permeability and less CO_2/CH_4 selectivity in comparison with PES–ESPU samples. For PES–ESPU membrane containing 1.5% ESPU, CO_2 permeance at 10 bar was improved up to 20% with almost no change in CO_2/CH_4 selectivity with respect to PES. Finally, response surface methodology was used to evaluate the effects of the operating parameters on the permeance and ideal selectivity.展开更多
Objective The dialysate membrane can be classified into acetate membrane and synthetic membrane,while the latter can be further divided into polysulfone,polyacrylonitrile,etc.Polyethersulfone membrane is high molecula...Objective The dialysate membrane can be classified into acetate membrane and synthetic membrane,while the latter can be further divided into polysulfone,polyacrylonitrile,etc.Polyethersulfone membrane is high molecular membrane material with excellent biocompatibility,stable mechanical properties,high temperature and pressure resistance,and good cleaning performance,which has been applied for more than 10 years.This trial is to assess the safety and efficacy of hollow polysulfone membrane fiber dialyzer with pattern number Enttex^(TM)-16LF(E60)for hemodialysis in patients with acute or chronic renal failure due to multiple factors.Methods Totally 76 patients receiving maintenance hemodialysis were included in a two-site,random,open label,two-stage,positive crossover and non inferiority validation study.The clinical efficacy and safety of the test device were observed,which was a hollow fiber dialyzer produced by Guangzhou Enttex Medical Products Co.,Ltd.,with polyethersulfone membrane imported from Germany.It was a low flux dialyzer with the pattern number of EnttexTM-16LF(E60).Inclusion criteria:①patients with acute or chronic renal failure due to various reasons who needed hemodialysis;②18 to 80 years old,gender unlimited;③patients who received stable dialysis for more than 3 months,regular hemodialysis 3 times a week,4 h at each time,blood flow rate of 200~350ml/min;④using bicarbonate dialysate at a flow rate of 500ml/min;⑤patients with arteriovenous fistula or who received artificial blood vessel puncture dialysis;received anticoagulation by heparin or low molecular weight heparin.Exclusion criteria:①patients needing heparin free dialysis for severe anemia,tumor and active bleeding;②patients with severe cardiac(gradeⅢcardiac function),hepatic(severe hepatitis and cirrhosis)and pulmonary diseases(severe respiratory failure).Results Comparison of parameters,including the changes of Kt/V,general creatinine and urea clearance rates and URR(urea reduction rate)shows no statistical significance in differences between the two devices,indicating that the test and control devices can equally and effectively eliminate toxins including creatinine and urea,etc.PPP and MITTP results are consistent.Comparison of ultrafiltration rates between two groups of patients shows no statistical difference.PPP and MITTP results are consistent,indicating that both the test device and control device can effectively eliminate water.In MITTP,electrolytes including K^+,Na^+,Cl^-,Ca^2+,HCO3^-,etc.show no statistical significance in difference between the test and control devices before and after dialysis(P>0.05).After treating by using test and control devices,body weight,serum potassium and phos-phorus all significantly decrease(P<0.001);serum Ca^2+,PO2,PCO2and HCO3^-all significantly increase(P<0.001).These results indicate that both the test and control devices can effectively eliminate serum potassium and phosphorus,and eliminate excess water in body,maintain the balance between liquid and electrolytes in patients.PPP and MITTP results are consistent.Conclusion This clinical trial confirms that hollow polyethersulfone membrane fiber dialyzer can be safely and effectively used in hemodialysis therapy.展开更多
基金the financial support from the National Natural Science Foundation of China (Nos50972070 and 51073105)Sichuan Youth Science and Technology Foundation(No08ZQ026-038)
文摘Well-defined amphiphilic tri-block copolymer PVP-b-PMMA-b-PVP was prepared for the first time via successive reversible addition fragmentation chain transfer(RAFT) polymerization using carboxyl-terminated trithiocarbonate as the RAFT agent.The structure of the copolymer was characterized using FTIR,GPC and ~1H NMR.The block copolymer could be directly blended with polyethersulfone(PES) as a macromolecule additive using N-methyl-2-pyrrolidone(NMP) as the solvent to prepare membranes. The water contact angles for the modified membranes decreased obviously,and therefore,the protein adsorption amount on the membrane surface decreased.
文摘The dual-bath coagulation method was used for the preparation of PES membrane in this experiment. The main intent of this stndy was to assess the efforts of gelation conditions on the structures and properties. The dense top layer as well as porous supporting layer can be made by duel-bath coagulation method simultaneous- ly. Different internal quench medium obtained different membrane with different structures. With the increase in time in the first coagulation bath, pure water flux decreased and the clearance rates of urea and creatinine both first increased then decreased and increased slightly in the end. With the temperature of the second coagtdation bath increasing, pure water flux increases and the clearance rates of urea and creatinine first increases then de- creases and increases a little at last. Higher DMSO concentration (wt/wt) in the second coagulation bath results in the increase of pure water flux and the decrease of urea & creatinine clearance rates.
文摘Objective: To observe the safety and efficacy of polyethersulfone membrane dialyzer used by chronic renal failure patients in clinical maintenance hemodialysis (MHD). Methods: From January to February 2009, 36 patients were recruited from Xinhua Hospital Affiliated to Shanghai Jiao Tong University School of Medicine. The experiment was approved by the ethnical committee of Xinhua Hospital and under permissions fronl patients. All the patients were randomized into polyethersulfone group (PES, n=18) and polysulfone group (PS, n=18). Hemodialysis was given by using Fresenius 4008S capacity-controlled dialyser and ultra-purified bicarbonate dialysate, more than 3.5 h each time, three times per-week, followed by heparin anticoagulation for a week, three times totally. Changes in blood urea nitrogen (BUN), serum creatinine (Set), phosphate (p2+), hemoglobin and albumin levels were determined for the efficacy and safety evahlation. Results: The serum BUN, Set and p2+ concentrations significantly reduced after hemodialysis with different dialyzers, and the decrease amplitude of two groups was equivalent(P〉0.05). The clearance rate of the serum BUN and Scr had no significant difference among two groups(P〉O.05). The clearance rate (ml/min) of the sermn P^2+ was 144.57 ±27.83 v.s. 117.15 ±22.77 in two groups. The clearance rate of the serum p^2+ in PES group was more than that in PS group, and the difference was significant between two groups (P=0.0001). It was indicated that PES and PS membrane could efficiently eliminate serum mieromolecule solute in MHD patients, so PES membrane excelled PS membrane in eliminating serum p2+. The hemodialysis safety index, for example serum hemoglobin, albumin and blood pressure, had no significant difference between the two groups before and after hemodialysis (P〉0.05). Conclusion: The efficacy and safety of the PES hollow fiber membrane dialyzer is equivalent to that of the imported PS membrane dialyzer in hemodialysis for MHD patients. The PES membrane excels PS membrane in eliminating sermn p^2+.
基金supported by the National Natural Science Foundation of China(Nos.51573041,21776067)the Demonstration Base Project of University-Enterprise Cooperation of Hunan Province(No.145812)。
文摘Hydrophilic modification is a promising method to inhibit fouling formation on ultrafiltration membrane.In this work,different mass concentrations(1%–16%)of hydrophilic polyvinylpyrrolidone were incorporated into polyethersulfone(PES)membranes fabricated by none-solvent induced phase separation.Then,polydopamine(PDA)coating on the surface of prepared membrane was carried out at pH 8.5.The morphology and structure,surface hydrophilicity,permeation flux,BSA rejection,antifouling and stability performances of PES and PDA/PES modified membranes were investigated in detail.The results indicated that PDA was successfully attached onto the membranes.Membrane hydrophilicity was evaluated by water contact angle measurement.The contact angles of modified membranes reduced remarkably,suggesting that the membrane hydrophilicities were significantly increased.The results of filtration tests,which were done by dead-end filtration of bovine serum albumin solution,showed that the properties of permeability and fouling resistance were obviously improved by PDA modification.When polyvinylpyrrolidone mass content reached 10%,flux recovery ratio of modified membrane was up to91.23%,and its BSA rejection were over 70%.The results of stability tests showed that the modified membranes had good mechanical stability and chemical stability.This facile fabrication procedure and outstanding performances suggested that the modified membranes had a potential in treating fouling.
文摘The transport performances of carbon dioxide and methane were studied in polyethersulfone, polyethersulfone/polyeterurethane(PES–ETPU) and polyethersulfone/polyestherurethane(PES–ESPU) blend membranes separately with different compositions. The variations in the structural characteristics of PES membrane after incorporation of ESPU and ETPU were investigated by different techniques. Additionally, the effect of pressure and composition on the permeance of CO_2, CH_4 and ideal selectivity of CO_2/CH_4 were checked on the membranes.The results revealed that the morphology of the blend membranes was affected by two opposite factors: thermodynamic enhancement and kinetic hindrance. The membranes with denser sponge layers were formed at lower ratio of PU/PES, while more porous structure with enlarged macrovoids membranes were observed at higher PU content. The results indicated that adding PU to PES membrane, caused permeance improvement of the gases with nearly no change and/or reduction in ideal selectivity of CO_2/CH_4. Moreover, PES–ETPU membranes showed higher permeability and less CO_2/CH_4 selectivity in comparison with PES–ESPU samples. For PES–ESPU membrane containing 1.5% ESPU, CO_2 permeance at 10 bar was improved up to 20% with almost no change in CO_2/CH_4 selectivity with respect to PES. Finally, response surface methodology was used to evaluate the effects of the operating parameters on the permeance and ideal selectivity.
基金Guangdong Provincial Science and Technology Department Fund Project(507204531040)Guangdong Provincial Science and Technology Plan Fund Project(2013b9040004)
文摘Objective The dialysate membrane can be classified into acetate membrane and synthetic membrane,while the latter can be further divided into polysulfone,polyacrylonitrile,etc.Polyethersulfone membrane is high molecular membrane material with excellent biocompatibility,stable mechanical properties,high temperature and pressure resistance,and good cleaning performance,which has been applied for more than 10 years.This trial is to assess the safety and efficacy of hollow polysulfone membrane fiber dialyzer with pattern number Enttex^(TM)-16LF(E60)for hemodialysis in patients with acute or chronic renal failure due to multiple factors.Methods Totally 76 patients receiving maintenance hemodialysis were included in a two-site,random,open label,two-stage,positive crossover and non inferiority validation study.The clinical efficacy and safety of the test device were observed,which was a hollow fiber dialyzer produced by Guangzhou Enttex Medical Products Co.,Ltd.,with polyethersulfone membrane imported from Germany.It was a low flux dialyzer with the pattern number of EnttexTM-16LF(E60).Inclusion criteria:①patients with acute or chronic renal failure due to various reasons who needed hemodialysis;②18 to 80 years old,gender unlimited;③patients who received stable dialysis for more than 3 months,regular hemodialysis 3 times a week,4 h at each time,blood flow rate of 200~350ml/min;④using bicarbonate dialysate at a flow rate of 500ml/min;⑤patients with arteriovenous fistula or who received artificial blood vessel puncture dialysis;received anticoagulation by heparin or low molecular weight heparin.Exclusion criteria:①patients needing heparin free dialysis for severe anemia,tumor and active bleeding;②patients with severe cardiac(gradeⅢcardiac function),hepatic(severe hepatitis and cirrhosis)and pulmonary diseases(severe respiratory failure).Results Comparison of parameters,including the changes of Kt/V,general creatinine and urea clearance rates and URR(urea reduction rate)shows no statistical significance in differences between the two devices,indicating that the test and control devices can equally and effectively eliminate toxins including creatinine and urea,etc.PPP and MITTP results are consistent.Comparison of ultrafiltration rates between two groups of patients shows no statistical difference.PPP and MITTP results are consistent,indicating that both the test device and control device can effectively eliminate water.In MITTP,electrolytes including K^+,Na^+,Cl^-,Ca^2+,HCO3^-,etc.show no statistical significance in difference between the test and control devices before and after dialysis(P>0.05).After treating by using test and control devices,body weight,serum potassium and phos-phorus all significantly decrease(P<0.001);serum Ca^2+,PO2,PCO2and HCO3^-all significantly increase(P<0.001).These results indicate that both the test and control devices can effectively eliminate serum potassium and phosphorus,and eliminate excess water in body,maintain the balance between liquid and electrolytes in patients.PPP and MITTP results are consistent.Conclusion This clinical trial confirms that hollow polyethersulfone membrane fiber dialyzer can be safely and effectively used in hemodialysis therapy.