Advances in liquid-phase microextraction technology and its application in biological sample pretreatment / 药学学报

Liquid-phase microextraction is a novel pretreatment technique for biological samples developed on the basis of liquid-phase extraction technology, which is simple, rapid, economical, and environmentally friendly, and has been widely used in the analysis of biological matrix samples such as blood, urine, and saliva. In this paper, we review the basic principles of the main modes of liquid-phase microextraction techniques, i.e., single-drop microextraction, dispersive liquid-liquid microextraction, and hollow-fiber liquid-phase microextraction, and the progress of their applications in biological sample pretreatment by reviewing the literature in the past five years, with a view to providing technical support and reference for sample pretreatment in the fields of in vivo drug analysis, pharmacokinetic studies and new drug development.

Desirability Function in analytical method development for determination of glitazones and metabolites employing HF-LPME

Abstract Thiazolidinedione, often shortened to TZD or glitazone, helps lower insulin resistance, which is the underlying problem for many people with type 2 diabetes. The two most known glitazones are pioglitazone (PGZ), with the brand name medicine Actos®, and rosiglitazone (RSG), which is Avandia®. This study presented a multivariate optimization in the microextraction procedure employing Fractional Factorial Design (FFD) combined with Desirability Function (DF) to determine TZD and metabolites in biological samples. Microextraction requires several parameters to be optimized; however, most of them still use univariate optimization. Finding optimum conditions by simple response is relatively simple, but the problems, in case of microextractions, are often more complex when it has more responses. For example, changing one factor that promotes one response may suppress the effect of the others. Thus, this multivariate optimization was applied for two bioanalytical methods for determination of TZD and metabolites, one by HPLC and other by CE, both using Hollow Fiber Liquid-Phase Microextraction (HF-LPME). The results establish the optimal values and elucidate how the factors that affect HF-LPME procedure perform in extraction efficiency for TZDs. Additionally, this study demonstrates that DF can be an important tool to optimize microextraction procedures.

Content Determination of Pulegone in Schizonepeta tenuifolia and Its Compound Preparation by Hollow Fiber Liquid-phase Microextraction Coupled with HPLC / 中国药房

OBJECTIVE：To establish t he metho d for the content determination of pulegone in Schizonepetae tenuifolia decoction pieces and its compound preparation. METHODS ：Hollow fiber liquid-phase microextraction coupled with HPLC （HF-LPME-HPLC） was adopted. Based on single factor tests ，HF-LPME condition of S. tenuifolia decoction pieces and its compound preparation （taking Compound S. tenuifolia granule as an expample ） was optimized by central composite design-response surface methodology using pulegone enrichment multiple as index ，with the concentration of sample phase solution （NaCl），extraction time and stirring speed as factors. Validation test was conducted. HPLC method was adopted to determine the content of pulegone. The determination was performed on Hypersil C 18 column with mobile phase consisted of methanol- 0.3％ phosphoric acid （gradient elution ）at the flow rate of 1.0 mL/min. The detection wavelength was set at 252 nm，the column temperature was 25 ℃. The sample size was 20 μL. The feasibility of HF-LPME-HPLC method established in this study was validated by using HPLC method stated in the item of S. tenuifolia decoction pieces in 2020 edition of Chinese Pharmacopoeia （part Ⅰ）as reference. RESULTS ：The optimum HF-LPME conditions included n-nonanol as the extraction solvent ，sample phase solution with 11％ NaCl and pH value of 7，stirring speed of 800 r/min，extraction time of 36 min. Results of HPLC methodology investigation showed that linear range of pulegone were 0.05-5 μg/mL（r＝0.999 0）. The limits of detection and quantitation were 0.4 and 1.3 ng/mL，respectively. RSDs of intra-day and inter-day precision were 1.8％-4.0％ and 1.5％-4.1％（n＝3），respectively. RSDs of reproducibility and stability tests （24 h）were all lower than 8％（n＝6）. Average recoveries of S. tenuifolia decoction pieces and Compound S. tenuifolia granule were 102.6％-105.1％ and 97.2％-102.3％，respectively；RSDs were not higher than 4.1％ and 6.2％（n＝3）. The average contents of pulegone in S. tenuifolia decoction pieces determined by pharmacopoeia method and established method were 0.84 mg/g（RSD＝4.3％ ，n＝3）and 0.87 mg/g（RSD＝5.5％ ，n＝3），respectively，with no significant difference （P＞0.05）. CONCLUSIONS ：The established HF-LPME-HPLC method can enrich and concentrate pulegone ， shows strong purification ability and high sensitivity ，and can be used to determine the contents of pulegone in S. tenuifolia decoction pieces and its compound preparation.

Perfusion enzyme affinity selection system based on hollow fiber for screening active compounds from total saponins of Kudingcha / 药学学报

Atherosclerosis is one of the causes of many cardiovascular diseases. Lipid metabolism disorder is an important risk factor for atherosclerosis. Lipase-targeted screening may help discovery of hypolipidemic and anti-atherosclerotic drugs. Traditional methods for enzyme-based screening exhibit drawbacks of tedious operation steps, reduced enzyme activity, slow mass transfer, as well as high false positive rate. In this paper, an integrated perfusion enzyme affinity selection system based on hollow fiber was constructed to screen hypolipidemic and anti-atherosclerotic compounds from traditional Chinese medicines, and the total saponins of Kudingcha were taken as a case. First, we built a hollow fiber based perfusion system and optimized the methodology for enzyme affinity selection. Then, two active compounds of kudinosides A and C were identified as potential lipase inhibitors from the total saponins of Kudingcha by the proposed system. Last, the activity of kudinosides A and C was verified by lipase inhibitory assay and formation of foam cell model induced by low density lipoprotein aggregates, exhibiting the reliability of the system. This platform shows the advantages of integration, fast mass transfer, simple operation, low cost, as well as improved throughput and efficiency, which is especially suitable for rapid screening active components from traditional Chinese medicine.

Development and optimization of perfusion process for mammalian cell culture / 生物工程学报

In recent years, the demand of biologics has increased rapidly. Cell culture process with perfusion mode has become more and more popular due to its high productivity, good quality and high efficiency. In this paper, the unique operation and the details of process optimization for perfusion culture mode are discussed by comparing with traditional batch culture process. Meanwhile, the progress and strategies in the development and optimization of perfusion culture process in recent years are summarized to provide reference for the future development of mammalian cell perfusion culture technology.

Hollow fiber-based liquid phase microextraction followed by analytical instrumental techniques for quantitative analysis of heavy metal ions and pharmaceuticals / 药物分析学报

Hollow-fiber liquid-phase microextraction (HF-LPME) and electromembrane extraction (EME) are miniaturized extraction techniques, and have been coupled with various analytical instruments for trace analysis of heavy metals, drugs and other organic compounds, in recent years. HF-LPME and EME provide high selectivity, efficient sample cleanup and enrichment, and reduce the consumption of organic sol-vents to a few micro-liters per sample. HF-LPME and EME are compatible with different analytical in-struments for chromatography, electrophoresis, atomic spectroscopy, mass spectrometry, and electrochemical detection. HF-LPME and EME have gained significant popularity during the recent years. This review focuses on hollow fiber based techniques (especially HF-LPME and EME) of heavy metals and pharmaceuticals (published 2017 to May 2019), and their combinations with atomic spectroscopy, UV-VIS spectrophotometry, high performance liquid chromatography, gas chromatography, capillary elec-trophoresis, and voltammetry.

Application of Hollow Fiber Ultrafiltration Technology in the Detection of Total IgE of Hemolytic Blood after Death / 法医学杂志

Objective To investigate the treatment effect of hollow fiber ultrafiltration technology on hemolytic samples and the differences between IgE concentration and serum concentration before hemolysis in ultrafiltrate. Methods The 33 postmortem blood samples of non-frozen corpses within 72 hours after death were collected, 4 mL blood was taken from each case, among which 1 mL was centrifuged to get serum, and the remaining 3 mL blood was frozen-thawed 3-5 times to cause complete hemolysis. The 2 mL hemolytic samples were processed by hollow fiber ultrafiltration to obtain ultrafiltrate. The hemoglobin concentration in serum, complete hemolytic sample and ultrafiltrate was determined by Van-Zij solution-cyanated methemoglobin assay method, and the total IgE in serum and ultrafiltrate was determined by electrochemical luminescence method. Results The hemoglobin concentration in ultrafiltrate was significantly lower than that in complete hemolytic samples （P<0.05）. There was a good correlation between the total IgE detection values of ultrafiltrate and serum （r=0.984）. The difference between the serum and the value of IgE in ultrafiltrate after correction had no statistical significance, and the differences between the two in positive rates had no statistical significance （P>0.05）. Conclusion Ultrafiltration technology has a good treatment effect on complete hemolytic samples, and the correction value of ultrafiltrate detection is close to the serum level before hemolysis, and therefore, it can be applied to the detection of total IgE of frozen corpse hemolytic samples.

Isolation and purification of Codonopsis pilosula polysaccharide and its anti-oxidant activity / 中草药

Objective: To isolate and purify the Codonopsis pilosula polysaccharide (CPP) and investigate its structure characterization and anti-oxidant activity. Methods: CPP was extracted by heating reflux, crud polysaccharide was refined and then isolated by hollow fiber ultrafiltration experimental device, the anti-oxidant activity of polysaccharides was studied by in vivo and in vitro methods. Results: CPP was purified and obtained three ingredients named CPP1, CPP2, and CPP3. The anti-oxidant activity in vitro showed that CPP3 had the strongest scavenging ability on DPPH, hydroxyl radical, and superoxide anion. In vivo study showed that high dose group of CPP3 had obvious protective effect on the mice induced by D-galactose. Conclusion: CPP has obvious anti-oxidant function. This study provides the theoretical basis for the development of CPP functional food.

Anti-tumor Activity of Saussurea laniceps against Pancreas Adenocarcinoma

The purpose of this study was to confirm the anti-tumor activity of an ethanol extract of Saussurea laniceps against pancreatic tumor and to isolate the active compound from S.laniceps extract. Treatment with S.laniceps extract and hispidulin inhibited proliferation of pancreatic cell lines, such as Capan-1, Capan-2, Panc-1 and S2-013 in a dose-dependent manner using the hollow fiber assay. Hispidulin showed typical hallmarks of apoptotic cell death a significant anti-tumor activity on Capan-2 cells at a dose of 100 mg/kg and 200 mg/kg. S.laniceps has potential cytotoxic and apoptotic effects on human pancreatic carcinoma cells. Its mechanism of action might be associated with the apoptotic cell death through DNA fragmentation.

Determination of Plasma Protein Binding Rate of Bisoprolol in Human Plasma by Hollow Fiber Liquid-phase Microextraction Combined with HPLC / 医药导报

Objective To develop a method for determination of the plasma protein binding rate of bisoprolol in human plasma by high performance liquid chromatography ( HPLC) combined with hollow fiber-based liquid-phase microextraction ( HF-LPME) . Methods Method of liquid phase microextraction was optimized. The concentration of bisoprolol in the reconstitute solution was analyzed by HPLC. The mobile phase consisted of water-methanol-acetonitrile-0. 1% phosphoric acid (50:34:6:10). The excitation wavelength was 232 nm and emission wavelength was 300 nm. Through the linear regression equations, the total and free concentrations were obtained, and then the protein binding rate was calculated. Results At low, middle, and high concentration, the protein binding rate of bisoprolol was 31. 2%, 32. 0% and 31. 8%, respectively. Conclusion The proposed method is proven to be simple, fast and reproducible, and is feasible for the determination of plasma protein binding rate of bisoprolol. Bisoprolol moderately binds with plasma protein independent of concentration.

Optimization of ultrafiltration technology for water extract in Cornus officinalis / 中草药

Objective: To explore the possibility for the application of ultrafiltration technology using polysulfone (PS) hollow fiber membrane to purlfy the water-extraction of Corni Fructus and optimize the preparation procedure. Methods: The PS membrane of different aperture 5×104, 1×104, and 6×103 were studied on the applicability with water-extraction of Corni Fructus. The proper molecular weight retention was optimized with the removal of liquid impurities and the transformation. Taking the ratios of loganin transmittance and common polymers (pectin, tannin, protein, and starch) retention as indexes, the proper ultrafiltration condition was optimized by response surface method. Results: The PS membrane with interception molecular weight of 1×104 had better separation efficiency and the preferred operation parameters were 0.1 MPa of pressure, 50℃ of liquid temperature, and solution concentration of 0.13 g/mL. Conclusion: The preferred aperture of PS membrane and the operation conditions are feasible for the purification of water-extraction of Corni Fructus, which can improve the production efficiency.

TiO2-coated Hollow Fiber Micro-Extraction Combined with Electrothermal Vaporization-Inductively Coupled Plasma Mass Spectrometry for Trace Elements Analysis in Environmental Water Samples / 分析化学

TiO2 coated hollow fiber ( HF) was prepared by sol-gel method and characterized by X-ray powder diffraction and scanning electron microscope. The adsorption performances of the self-prepared TiO2 coated HF for interest metal ions were explored. The sample solution was extracted for 30 min at pH 8. 0 under stirring at speed of 700 r/min, then desorpted with 100μL of 1 mol/L HNO3 . On the basis of this, a method combining TiO2 coated HF micro-solid phase extraction with electrothermal vaporization-inductively coupled plasma mass spectrometry ( ICP-MS ) was developed for the determination of trace metal ions in environmental water samples. Under the optimized conditions, the limits of detection obtained by the proposed method were 0. 039, 0 . 021 , 0 . 009 and 0 . 018 ng/mL for CrⅢ, CuⅡ, CdⅡ and PbⅡ with enrichment factors of 12 . 5 , 11 . 7 , 10. 3 and 18. 6, respectively. The preparation reproducibility of self-prepared TiO2 coated HF ranged from 4. 5% to 6. 8% (n=9) in one batch, and from 7. 7% to 9. 6% (n=7) in batch-to-batch. The developed method has been validated by analyzing a certified reference material ( GSBZ50009-88 200925 ) and also applied to the analysis of CrⅢ, CuⅡ, CdⅡ and PbⅡ in East Lake water and snow water successfully. Meanwhile, TiO2 coated HF stir bar was prepared for a comparison and it was demonstrated that TiO2 coated HF displayed higher extraction efficiency and adsorption capacity for target ions.

Determination of Perfluorinated Compounds in Water by Electrospray Ionization Mass Spectrometry Combined with Hollow Fiber Membrane Extraction / 分析化学

In this study, hollow fiber membrane extraction combined with ambient ionization mass spectrometry ( AMS) was developed for the simultaneous determination of 7 perfluorinated compounds ( PFCs) in aqueous solution, including perfluoroheptanoic acid ( PFHpA ) , perfluorooctanoic acid ( PFOA ) , perfluorooctane sulfonate acid ( PFOS ) , perfluorononanoic acid ( PFNA ) , perfluorodecanoic acid ( PFDA ) , perfluoroundecanoic acid ( PFUdA) , and perfluorododecanoic acid ( PFDoA) . PFCs were detected in negative ion mode using selective reaction monitoring ( SRM) mode. The extraction time and the pH value of extraction solution were optimized. 13 C4-PFOS and 13 C4-PFOA were used as internal standards for quantitative analysis. The method showed good linearity with correlation coefficient values ( r2 ) greater than 0. 991 for the seven target PFCs. With the exception of PFHpA, the limit of detection ( LOD) for other six PFCs was within ranges from 0. 8 to 2. 7 ng/L while the limit of quantitative (LOQ) was from 2. 7 ng/L to 8. 9 ng/L. The enrichment factor of five PFCs was more than two hundred. The developed method was applied to detect the seven PFCs in tap water and Pearl River water, and they were all not detected. The recoveries were within the ranges of 88. 5%-108. 3% and 94. 2%-116. 7% when 40 ng/L and 400 ng/L PFCs were spiked into tap water, respectively. In terms of the Pearl River water, the recoveries were within the ranges of 75. 0%-102. 6% and 81. 2%-97. 6% when 40 ng/L and 400 ng/L PFCs were spiked, respectively.

Evaluation of the inhibitory effect of garcinia glycosides on growth of human tumor cells by hollow fiber assay / 药学实践杂志

Objective To evaluated the inhibitory effect of garcinia glycosides on growth of 8 kinds of human tumor cells in vi-vo by hollow fiber assay and confirm the reliability of hollow fiber assay in anticancer effect by the nude mice xenograft test .Methods Hollow fibers containing tumor cells were inserted underneath the skin of the NOD /SCID mice.The fibers were collected from the mice on the day after the administration and subjected to the stable endpoint MTT assay .The tumor cells of HL-60 and B16 were subcutane-ously implanted into the right flank of BALb /c nude mice.The positive control group was treated with cyclophosphamide .Each group was administered for 10 days.24 hours after the last administration , the mice were sacrificed and the tumors were excised and weigh-ted, the inhibition rate of tumor growth was calculated .Results The high-dose group of 8 mg/( kg· d) , middle dose group of 4 mg/( kg· d) of garcinia glycosides were measured by hollow fiber assay and nude mice test significantly inhibited the in vivo growth of HL -60 and B16 comparing with those in the solvent control group (P<0.01).Conclusion As a new model by hollow fiber assay to evalu-ate the inhibitory effect of garcinia glycosides , the test results were basically the same with nude mice test results .It made the experi-ment more rapidly , accurately and economically .An instruction and reliable evidence for follow-up study of garcinia glycosides was provided in this study .

Derivatization at Injection Port Following Hollow Fiber Microextraction with Tetramethylammonium Hydroxide for Determination of Six Phenolic Acids in Beers by Gas Chromatography / 分析化学

A method of derivatization at injection port following three phase hollow fiber microextraction with tetramethylammonium hydroxide (TMAH) as a dual-function reagent, for the simultaneous determination of salicylic acid, p-hydroxybenzoic acid, cinnamic acid, vanillic acid, p-coumaric acid and ferulic acid in beers by gas chromatography was developed. Phenolic acids were extracted from aqueous samples to a thin layer of organic solvent ( hexyl acetate) phase impregnated into the pores of the hollow fiber wall, and then back extracted to an acceptor solution (TMAH) located inside the lumen of the hollow fiber. Upon injection, the phenolic acids were derivatized to their methyl esters in the GC injection port. Several parameters related to the derivatization and extraction efficiency were optimized. The optimized conditions were as follows: hexyl acetate was used as the extraction solvent, an aqueous solution of TMAH (5% W/ V) was used as the derivatization reagent and acceptor phase, the pH value of donor phase was 2. 0, the concentrations of NaCl was 25% W/ V, the stirring rate was 500 r/ min, the extraction time was 40 min. Under the optimal conditions, the linear range of phenolic acids was 0. 50 -15. 00 mg / L, the limits of detection were 0. 05 -0. 18 mg / L. The proposed method was applied to the determination of the phenolic acids in beers. Vanillic acid, p-coumaric acid and ferulic acid were found in the beer samples, others were not detected. The spiked average recoveries were 90. 1% -106. 8% and RSD% was less than 5. 9% (n =3). The method is suitable for the determination of phenolic acids in beers.

Preclinical Efficacy Testing for Stomach and Liver Cancers / Journal of the Korean Cancer Association, 대한암학회지

PURPOSE: Hollow fiber assays offer an early in vivo method of anticancer drug screening. The assays have been optimized for human cancers originating from the lung, breast, colon, ovary, and brain, but not from the stomach and liver. The current study focused on optimization of hollow fiber assays for gastric and hepatocellular carcinoma cell lines. MATERIALS AND METHODS: Gastric (SNU-16, SNU-484, SNU-668) and hepatocellular (HepG2, SK-Hep-1, Hep3B) carcinoma cell lines in hollow fibers were transplanted subcutaneously and intraperitoneally into mice, which were subsequently treated with a standard anticancer agent, paclitaxel. The hollow fiber activity of paclitaxel in each cell line was compared with the xenograft activity. RESULTS: Using optimized inoculation densities and schedules, treatment with paclitaxel was effective in gastric carcinoma cell lines, SNU-16 and SNU-484, but not in SNU-668. In the hollow fiber assays, paclitaxel was effective in hepatocellular carcinoma cell lines, HepG2 and SK-Hep-1, but not in Hep3B. Consistent with the results of the hollow fiber assay, SNU-16 and SNU-484, but not SNU-668, showed tumor regression, and HepG2 and SK-Hep-1, but not Hep3B, showed effective tumor responses following treatment with paclitaxel in xenograft models. When EW7197, a novel compound, and flavopiridol were tested in SNU-16 cells under optimized conditions, the hollow fiber activity showed good correlation with the xenograft activity of each compound. CONCLUSION: Our protocols may be useful for screening candidate small molecules that may exhibit activity against stomach and liver cancers, both of which are common in Korea.

Adaptability research on ultrafiltration process of microfiltrated Qihong Maitong Injection / 中草药

Objective: To study the application of four kinds of hollow fiber ultrafiltration membranes by taking Qihong Maitong Injection (QMI) microfiltrated liquid as the research object. Methods: Polysulfone, polyether sulfone, polypropylene, and blended composite membranes with the entrapment relative molecular mass of 100000 for ultrafiltration were selected to determine the best appropriate ultrafiltration membrane material. The membrane flux of ultrafiltration was determined by taking the content of active ingredients (Astragalus total saponin, astragaloside IV, and hydroxy safflower yellow A), solid reduction rate, protein reduction rate, related substances, and pyrogen inspection of different membrane materials as the evaluation indexes. Results: The suitability of four different kinds of ultrafiltration membrane materials with the same entrapment relative molecular mass was different. The pure water flux recovery rates of polypropylene, polyether sulfone, and blended composite materials are higher than that of polysulfone material. The component permeation rates of polypropylene and polyether sulfone materials were higher, while the solid and protein reduction rates of polysulfone and blend compound materials were higher. For QMI, the ultrafiltration membrane with entrapment relative molecular mass of 100000 could effectively remove the pyrogen. Conclusion: The polypropylene-100000 ultrafiltration membrane could not only effectively remove the solid and high polymer material, but also keep the active ingredients. It is suitable for the purification of QMI.

Purification technology for decarburization fluid of Reduning Injection by polysulfone ultrafiltration membrane / 中草药

Objective: To investigate the ultrafiltration effect of polysulfone hollow fiber ultrafiltration membrane and polysulfone plate ultrafiltration membrane with relative molecular weight by different cut-off on the decarburization fluid of Reduning Injection. Methods: The transfer rates of chlorogenic acid and geniposide, fingerprint similarity, and removal of bacterial endotoxin, protein, oxalate, and resin before and after ultrafiltration were used as inspect indicators to optimize the purification technology for the decarburization fluid of Reduning Injection. Results: The obvious effect of polysulfone hollow fiber ultrafiltration membrane with the relative molecular weight 10000 on oxalate and resin in the decarburization fluid of Reduning Injection was observed. Bacterial endotoxin (100%) in the decarburization fluid of Reduning Injection was removed by the polysulfone plate ultrafiltration membrane with the relative molecular weight 5000. Conclusion: The stability and the preparation safety of Reduning Injection could be ensured by the two stage combination of the ultrafiltration membrane technology.

The Toxicity and Anti-cancer Activity of the Hexane Layer of Melia azedarach L. var. japonica Makino's Bark Extract

In this study, the 4-week oral toxicity and anti-cancer activity of the hexane layer of Melia azedarach L. var. japonica Makino's bark extract were investigated. We carried out a hollow fiber (HF) assay and 28-day repeated toxicity study to confirm the anti-cancer effect and safety of the hexane layer. The HF assay was carried out using an A549 human adenocarcinoma cell via intraperitoneal (IP) site with or without cisplatin. In the result, the 200 mg/kg b.w of hexane layer with 4 mg/kg b.w of cisplatin treated group, showed the highest cytotoxicity aginst A549 carcinoma cells. For the 28-day repeated toxicity study, 6 groups of 10 male and female mice were given by gavage 200, 100, or 50 mg/kg b.w hexane layer with or without 4 mg/kg b.w of cisplatin against body weight, and were then sacrificed for blood and tissue sampling. The subacute oral toxicity study in mice with doses of 200, 100, and 50 mg/kg b.w hexane layer showed no significant changes in body weight gain and general behavior. The cisplatin-treated group significantly decreased in body weight compared to the control group but regained weight with 100 and 200 mg/kg b.w of hexane layer. The biochemical analysis showed significant increase in several parameters (ALT, total billirubin, AST, creatinine, and BUN) in cisplatin-treated groups. However, in the group given a co-treatment of hexane layer (200 mg/kg b.w), levels of these parameters decreased. In hematological analysis, cisplatin induced the reduction of WBCs and neutrophils but co-treatment with hexane layer (100 and 200 mg/kg b.w) improved these toxicities caused by cisplatin. The histological profile of the livers showed eosinophilic cell foci in central vein and portal triad in cisplatin treated mice. These results show that hexane layer might have an anti-cancer activity and could improve the toxicity of cisplatin.

Avaliação do desempenho operacional de dialisadores de fibra oca de polietersulfona em condições de usos múltiplos / Evaluation of the performance of hollow-fiber hemodialyzers with a polyethersulfone membrane in multiple use conditions

Introdução: A qualidade do tratamento hemodialítico depende das características da membrana utilizada. O objetivo deste estudo foi avaliar o desempenho de dialisadores de fibra oca de polietersulfona na condição de usos múltiplos. Métodos: Trinta pacientes em programa de diálise, previamente dialisados com membranas de polisulfona, passaram a ser dialisados com membranas de polietersulfona. Os filtros foram reutilizados através de técnicas de reprocessamento automático. As concentrações de uréia, creatinina, fósforo e β2microglobulina (β2MG) foram avaliadas no 1º, 6º, 12º e 18º usos. A eficiência da diálise foi avaliada pelo Kt/V de uréia. Resultados: Nove filtros apresentaram ruptura da membrana durante o reprocessamento, tendo sido o problema resolvido após ajustes na pressão de água na sala de reuso. Um paciente foi excluído por apresentar trombose da fístula arteriovenosa. Vinte pacientes completaram o estudo, nos quais a concentração pré-diálise de uréia, creatinina, fósforo e o Kt/V não se modificaram durante a realização doestudo. Entretanto, houve uma redução significativa no nível sérico de β2MG pré-diálise após a troca para os dialisadores de polietersulfona (42,5±6,8 vs 27,6±3,1mg/dL; p<0,05). Ocorreu, também, uma redução média de 28% no nível sérico pré e pós-diálise de β2MG, sendo que a intensidade dessa redução não foi influenciada pelo reuso do capilar. Conclusões: Nosso estudo mostra que o reuso de dialisadores com membrana de polietersulfona não se associa com redução do desempenho do filtro. O nível sérico pré-diálise de β2MG se reduziu após a transferência de polisulfona para polietersulfona, sendo que essa redução não foi influenciada pelo reuso do filtro.

Introduction: The quality of the hemodialysis therapy depends on the properties of the dialyzer membrane. The aim of this study was to evaluate the performance of hollow fiber hemodialyzers with polyethersulfone membranes in conditions of multiple use. Methods: Thirty patients on maintenance hemodialysis were switched from polysulfone to polyethersulfone membranes. The filters were reused by automatic techniques of dialyzer reuse. The blood urea, creatinine, phosphorus and β2microglobulin (β2MG) concentrations were measured in the 1st, 6th, 12th and 18th use. The efficiency of the dialysis was evaluated by urea Kt/V. Results: Rupture of polyethersulfone membrane was observed in nine filters during reuse, and the problem was resolved after adjustments in the water pressure in the reuse room. One patient was excluded from the study due to thrombosis of the arteriovenous access. Twenty patients completed the study. For these patients, there were no changes in pre-dialysis blood urea, creatinine and phosphorus concentration during the study. Also, there was no difference in Kt/V. However, there was a significant reduction in pre-dialysis β2MG concentration after having switched to polyethersulfone membrane (42.5±6.8 vs. 27.6±3.1mg/dL; p<0.05). Furthermore, we observed a decrease of 28% between pre and post dialysis β2MG concentration, and no relationship between β2MG concentration pre and post dialysis and dialyzer reuse. Conclusions: Our study suggests that the reuse of the polyethersulfone hemodialyzer is not associated with changes in performance of the filter. Neither the predialysis β2MG concentration decrease after switching the patient from polysulfone to polyethersulfone membrane nor the intensity of this reduction is influenced by filter reuse.