一种类风湿因子血液净化吸附剂的制备与性能评价

研究的目的是制备一种吸附剂用于清除患者血液中大量的类风湿因子,并对制备的吸附剂进行吸附性能评价.首先制备了大孔聚乙烯醇微球载体,经活化后固定苯丙氨酸作为配基形成类风湿因子吸附剂,通过体外静态和动态吸附实验对其吸附性能以及相关的影响因素做系统的评价.结果表明,该吸附剂能够在短时间内快速吸附类风湿因子,具有较高的吸附效率(约60%)和吸附容量(750 IU/mL),适宜用作血液灌流去除类风湿因子的吸附剂.     

固相载体微球的制备

国内外研制的放射免疫试剂盒多为液相竞争法。固相放射免疫分析法是近年来的一项新技术。此法操作简单,稳定性好,非特异性吸收低,固相载体在放射免疫分忻领域中取得日益广泛的用途,将成为一项富有生命力的新技术。 本文经过一系列的实验,着重研究了各种粒径大小,带不同官能团的载体微球的制备方法,探讨了不同的材料和工艺所制成的载体微球所具有的不同的物理性质,对放射免疫分析的不同影响,为固相放射免疫分析技术的发展打下了基础。 材料和方法 一、试剂与设备: (一)试剂:单体 丙烯酰胺 丙烯酸 孔化剂 司本-80 十二烷基苯磺酸钠 分散剂 明胶(0.5％) 引发剂 过硫酸胺(2.5％) 过氧化苯甲酰 交联剂 N,N′—甲叉双丙烯酰胺 (二)设备:电子恒速搅拌器 型号 CSl2—2 多功能电子恒温水浴箱 三口圆底烧瓶 0.5升 二、固相微球的制备:固相微球一般用人工合成     

琼脂凝胶键连热聚IgG——一种新型类风湿关节炎免疫吸附剂

将热聚IgG固载到琼脂凝胶珠上 ,制成了一种特异性类风湿关节炎免疫吸附剂。体外吸附实验表明该吸附剂对类风湿因子及其免疫复合物具有强的选择吸附性能 ,活体动物全血灌流实验证明该吸附剂具有良好的血液相容性和机械强度     

影响微球药物释放因素的研究

目的 观察影响微球药物释放的因素，为其应用提供理论基础。方法 以可生物降解的聚乳酸—聚乙醇酸共聚物(PLGA)和聚L—乳酸(PLIA)为载体，采用乳化—溶剂挥发法制备含细胞松弛素B(cytoB)微球，以HPLC测定cy-toB含量。结果 制备了不同球径的微球，其球径分别为150nm、500nm、1μm、5μm、10μm和20μm。体外释放实验证明，球径越小，药物释放速度越快；球径相同时，以PLIA为基材的微球比PLGA的释放慢。结论 可通过选择适当的微球大小和基质材料达到所期望的药物释放过程。     

利福平/聚乳酸-聚羟基乙酸缓释微球的制备及特性

背景：虽然国内外有很多制备利福平/聚乳酸-聚羟基乙酸共聚物(poly lactic acid-glycolic acid copolymer,PLGA)微球的报道,但这些微球粒径多在10 μm左右,不适合与磷酸钙骨水泥复合制备成具有良好降解性的抗结核修复材料。 目的：制备大粒径利福平/PLGA缓释微球,观察其理化特性和体外缓释特性。 方法：以PLGA为载体,将利福平分散于PLGA的有机溶剂中,采用复乳溶剂挥发法制备利福平/ PLGA缓释微球。光镜和扫描电镜下观察微球的形态特征,测定微球平均直径和跨距,高效液相色谱法测定载药量和包封率,以溶出法和高效液相色谱法观察其体外释药特性,并拟合药物体外释放曲线建立曲线方程。 结果与结论：利福平/PLGA微球电镜观察呈圆球形,分散性好,粘连少,粒径分布集中,平均粒径(80.0±9.4) μm。载药量、包封率分别为(33.18±1.36)%,(54.79±1.13)%。体外缓释试验显示突释期内微球释放度为(14.66±0.18)%,前3 d累计释放度(18.09±0.45)%,到42 d体外累积释放度达到(92.17±1.23)%。提示利福平/PLGA微球具有良好的缓释效果,是一种较为理想的抗结核药物的载体材料和释放系统;PLGA是良好的药物缓释载体,可以用来制备载药缓释微球。     

羧甲基壳聚糖-聚乙二醇双缩水甘油醚微球的制备及对脂蛋白吸附选择性的研究

目的制备血清中低密度脂蛋白选择性吸附微球，探讨影响微球对血清脂蛋白吸附选择性的因素。方法用静电滴液发生法制备羧甲基壳聚糖凝胶微球，与交联剂聚乙二醇双缩水甘油醚交联。制得羧甲基壳聚糖-聚乙二醇交联微球，测定微球对血清脂蛋白吸附。结果增加羧甲基壳聚糖的浓度，微球的吸附速度及选择性均增加，增加交联剂用量，吸附剂对LDL的吸附性能先提高，而后降低。对HDL的吸附量则为先减小后增大。结论羧甲基壳聚糖为3.5％、聚乙二醇双缩水甘油醚为6％时，制备的微球对血清中的低密度脂蛋白的去除率可达40％，而同时对高密度脂蛋白的吸附低于10％，且在30min即可达到吸附平衡。     

血清胺特异性识别荧光探针的制备与表征

目的 在CdTe@SiO2量子点(QDs)表面进行分子印迹,合成出对血清胺具有特异性识别的荧光探针.方法 首先在水相中合成CdTe@SiO2 QDs,然后以血清胺为模板分子、3-氨丙基三乙氧基硅烷(APTES)为功能单体、正硅酸四乙酯(TEOS)为交联剂合成分子印迹聚合物(MIP),并采用荧光分析法对CdTe@SiO2@MIP的性能进行表征.结果 吸附实验表明,在相同的浓度下,血清胺对CdTe@SiO2@MIP的荧光猝灭程度远远大于对CdTe@SiO2@NIP的荧光猝灭程度.结论 合成的印迹聚合物对血清胺具有一定的特异性识别能力.     

一种新型热敏聚乳酸微球的制备与表征

背景：目前,基于聚乳酸的智能型微球是药物可控释放研究领域的热点。 目的：制备一种温度响应可控、生物可降解的微球载体。 方法：以甲基丙烯酸-2-羟乙酯作为丙交酯开环的引发剂,采用辛酸亚锡作为催化剂,并调节乳酸与甲基丙烯酸乙酯的比例,得到了不同分子质量的带双键聚乳酸(PDLLA-EMA)。以甲苯为溶剂,采用溶液合成法,自由基反应引发含有双键的聚乳酸以及N,N-异丙基丙烯酰胺共聚,成功制得了可降解温敏型共聚物(PNIPA-g-PDLLA-EMA)。采用复乳法,将PNIPA-g-PDLLA-EMA制成了微球。 结果与结论：实验制得PNIPA-g-PDLLA-EMA材料的热响应温度范围为35~42 ℃,基于该材料制得的微球粒径范围为(13.70±0.70)~(28.90±0.50) μm,粒径变化率为(138.7±4.20)%~(170.0±10.00)%,与同类材料相比,该微球已具备了应用于生物医学的潜在条件。关键词：智能型微球;可生物降解;聚乳酸;制备;载体 缩略语注释：PNIPAm：Poly N-isopropylacrylamide,聚(N-异丙基丙烯酰胺) doi:10.3969/j.issn.1673-8225.2012.16.015     

聚乙二醇-b-聚己内酯/聚己内酯单分散电喷微球的制备与亲水性研究

用静电喷雾法制备单分散性良好、亲水性的聚乙二醇-b-聚己内酯/聚己内酯(PEG-b-PCL/PCL)电喷微球。将聚乙二醇-b-聚己内酯(PEG-b-PCL)、聚己内酯(PCL)与氯仿混合磁力搅拌3 h后,采用静电喷雾的方法,以双亲(PEG-b-PCL)含量、流速、电压为变量,研究微球形态大小、粒径分布的变化,并研究微球亲水性随双亲含量的变化程度及微球在水中的分散性。双亲含10%～20%、流速1 mL/h、电压10 kV时能得到成球性佳、粒径5～6 μm的单分散性良好的微球,粒径的变异系数为15%～21%;双亲含量增至30%,微球之间由较多的纤维连接;双亲含量由0增至20%时,接触角由126.2°±4.8° 降至29.9°±4.9°,差异具有统计学意义(P<0.05),通过改变双亲含量能有效改善微球的亲水性,同时,加入10%～20%双亲的微球在水中分散性佳,能形成均匀的混悬液。PEG-b-PCL/ PCL能得到单分散、亲水性佳的微球,为进一步制备载药微球提供条件。     

磷酸盐型低密度脂蛋白亲和吸附剂制备与体外吸附试验研究

研究目的是制备低密度脂蛋白亲和吸附剂,用于去除高脂血症患者血液中高含量的低密度脂蛋白。首先以悬浮分散法制备壳聚糖微球和纤维素微球载体,然后固定磷酸吡哆醛和磷酸盐配基,制备出三种吸附剂,并进行体外静态吸附性能测试。结果表明,壳聚糖-磷酸吡哆醛吸附剂对LDL最大吸附量为1.30mg/mL,磷酸盐型壳聚糖和纤维素吸附剂对LDL的最大吸附量分别为2.72mg/mL和3.12mg/mL,并且吸附量随配基含量的增加呈增大趋势,3种吸附剂对高密度脂蛋白均无明显吸附。对吸附剂的灭菌和储存稳定性的研究表明,磷酸盐型纤维素吸附剂具有较好的稳定性。本研究第一次报道磷酸盐型低密度脂蛋白吸附剂。     

Chitosan adsorbents carrying amino acids for selective removal of low density lipoprotein

Chitosan beads carrying various amino acids (a total of 12 kinds) were synthesized through quite simple procedures for selective removal of low density lipoprotein (LDL). Macroporous chitosan beads were prepared by the phase-inversion method, to which the amino acids were then coupled respectively, via either ethyleneglycol diglycidylether (EGDE) or epichlorohydrin (ECH). Among the amino acids used, in vitro tests proved L-Trp to be the best ligand for binding LDL. The adsorbent, which was prepared by coupling L-Trp to the chitosan beads via EGDE, demonstrated satisfactory adsorption performance for selective removal of LDL in human plasma.     

Poly(α-amino acid)-immobilized polymer adsorbents for optical resolution, 2. Effect of crosslinking degree of the support resin on the resolution efficiency

Polymer adsorbents for chromatographic optical resolution were synthesized by grafting poly(N⁵-benzyl-L -glutamine-co-γ-benzyl L -glutamyl) onto cross-linked polystyrene beads. The effects of the crosslinking degree (1,5%, 9%, 30%) and the porosity of the polystyrene matrix on the resolution efficiency of the adsorbent were investigated. Similar resolution efficiencies were observed on 1,5% cross-linked gel (non-porous) and 9% cross-linked porous adsorbents, while a decline in the efficiency was observed on 30% cross-linked porous adsorbent. Studies of transmission electron micrographs of these adsorbent clearly showed the effect of degree of crosslinking on the distribution manner of the incorporated poly(α-amino acid). At a degree of 30%, clustered incorporation occurs mainly on the pore surface and not within the cross-linked polymer matrix. Such incorporation manners are also suggested by the swelling properties of the adsorbents. Pore volumes, pore radii, and specific surface areas of the adsorbents were also measured. It was observed that uniform incorporation of poly(α-amino acid) derives a higher resolution efficiency of the adsorbent.     

Immobilized metal affinity beads for ferritin adsorption

A new metal-chelate adsorbent utilizing N-methacryloyl-(L)-cysteine methyl ester (MAC) was prepared as a metal-chelating ligand. MAC was synthesized by using methacryloyl chloride and L-cysteine methyl ester dihydrochloride. Spherical beads with an average diameter of 150-200 microm were produced by suspension polymerization of 2-hydroxyethyl methacrylate (HEMA) and MAC carried out in an aqueous dispersion medium. Then, Fe(3+) ions were chelated directly on the beads. Properties such as specific surface area, specific pore volume and ligand occupation were determined. The specific surface area of the beads was found to be 18.9 m2/g. The total pore volume was 2.8 ml/g and represented a porosity over 52%. The average pore size of the poly(HEMA-MAC) beads was 620 nm. Fe(3+)-chelated beads were used in the adsorption of ferritin from aqueous solutions. Ferritin adsorption increased with increasing ferritin concentration. The maximum ferritin adsorption capacity of the Fe(3+)-chelated poly(HEMA-MAC) beads (Fe(3+) loading 0.81 mmol/g) was found to be 3.7 mg/g at pH 4.0 in acetate buffer. The non-specific ferritin adsorption on the poly(HEMA-MAC) beads were 0.4 mg/g. Adsorption behavior of ferritin could be modelled using both the Langmuir and Freundlich isotherms. Adsorption capacity decreased with increasing ionic strength of the binding buffer. Ferritin molecules could be adsorbed and desorbed five times with these adsorbents without noticeable loss in their ferritin adsorption capacity.     

Cellulose amphiphilic adsorbent for the removal of low density lipoprotein

Cellulose adsorbent with amphiphilic ligands for adsorption of low density lipoprotein (LDL) was prepared by the following procedures: Cellulose beads were reacted with cholesterol N-(6-isocyanatohexyl) carbamate in the presence of pyridine in DMSO at 80 degrees C in order to introduce the hydrophilic moiety, it was then reacted with chlorosulfonic acid in dimethyl formamide, which introduced the sulfonic group. Adsorption capacity of adsorbent was studied, which showed the removal of LDL, TC, TG to be 0.857 mg/ml, 1.317 mg/ml, 1.002 mg/ml respectively without significantly affecting total protein levels in the plasma. Moreover, it has a better selectivity in removing LDL, TC, TG compared with cellulose adsorbent with only hydrophobic or hydrophilic ligand.     

Immobilized metal affinity beads for ferritin adsorption

A new metal–chelate adsorbent utilizing N-methacryloyl-(L)-cysteine methyl ester (MAC) was prepared as a metal-chelating ligand. MAC was synthesized by using methacryloyl chloride and L-cysteine methyl ester dihydrochloride. Spherical beads with an average diameter of 150–200 μm were produced by suspension polymerization of 2-hydroxyethyl methacrylate (HEMA) and MAC carried out in an aqueous dispersion medium. Then, Fe³⁺ ions were chelated directly on the beads. Properties such as specific surface area, specific pore volume and ligand occupation were determined. The specific surface area of the beads was found to be 18.9 m²/g. The total pore volume was 2.8 ml/g and represented a porosity over 52%. The average pore size of the poly(HEMA-MAC) beads was 620 nm. Fe³⁺ -chelated beads were used in the adsorption of ferritin from aqueous solutions. Ferritin adsorption increased with increasing ferritin concentration. The maximum ferritin adsorption capacity of the Fe³⁺ -chelated poly(HEMA-MAC) beads (Fe³⁺ loading 0.81 mmol/g) was found to be 3.7 mg/g at pH 4.0 in acetate buffer. The non-specific ferritin adsorption on the poly(HEMA-MAC) beads were 0.4 mg/g. Adsorption behavior of ferritin could be modelled using both the Langmuir and Freundlich isotherms. Adsorption capacity decreased with increasing ionic strength of the binding buffer. Ferritin molecules could be adsorbed and desorbed five times with these adsorbents without noticeable loss in their ferritin adsorption capacity.     

Synthesis and in vitro sorption properties of PAA-grafted cellulose beads for selective binding of LDL

Poly(acrylic acid) (PAA)-grafted cellulose copolymer beads were synthesized and tested in vitro as an adsorbent for selective removal of low-density lipoprotein (LDL) from human plasma. The copolymers were prepared by graft copolymerization of acrylic acid (AA) onto porous cellulose beads using cerium ammonium nitrate (CAN) as an initiator. The effect of initiator concentration, monomer amount and reaction time on the grafting was examined, and it revealed that the extent of grafting could be controlled by setting the appropriate reaction conditions. In vitro batch-wise adsorption tests were conducted to evaluate the lipoprotein sorption properties of the resulted copolymer beads, and the effect of grafting conditions on the adsorption performance was investigated. It was shown that the binding capacities of the best adsorbent derived from the appropriate reaction conditions could reach 4.96 mg/g total cholesterol (TC) and 4.46 mg/g LDL cholesterol (LDL-C) from human plasma, respectively, without significantly affecting the contents of beneficial constitutes such as high-density lipoprotein (HDL) and total proteins (TP). The influences of plasma amount and adsorption period on the adsorption properties were also determined and analyzed. It appears that this kind of copolymer is worthy of being developed as an alternative LDL adsorbent.     

First steps towards tissue engineering of small-diameter blood vessels: preparation of flat scaffolds of collagen and elastin by means of freeze drying

Porous scaffolds composed of collagen or collagen and elastin were prepared by freeze drying at temperatures between -18 and -196 degrees C. All scaffolds had a porosity of 90-98% and a homogeneous distribution of pores. Freeze drying at -18 degrees C afforded collagen and collagen/elastin matrices with average pore sizes of 340 and 130 mum, respectively. After 20 successive cycles up to 10% of strain, collagen/elastin dense films had a total degree of strain recovery of 70% +/- 5%, which was higher than that of collagen films (42% +/- 6%). Crosslinking of collagen/elastin matrices either in water or ethanol/water (40% v/v) was carried out using a carbodiimide (N-(3-dimethylaminopropyl)-N'-ethylcarbodiimide hydrochloride, EDC) in combination with a succinimide (N-hydroxysuccinimide, NHS) in the presence or absence of a diamine (J230) or by reaction with butanediol diglycidylether (BDGE), followed by EDC/NHS. Crosslinking with EDC/NHS or EDC/NHS/J230 resulted in matrices with increased stiffness as compared to noncrosslinked matrices, whereas sequential crosslinking with the diglycidylether and EDC/NHS yielded very brittle scaffolds. Ethanol/water was the preferred solvent in the crosslinking process because of its ability to preserve the open porous structure during crosslinking. Smooth muscle cells were seeded on the (crosslinked) scaffolds and could be expanded during 14 days of culturing.     

新型LDL-吸附剂对血脂影响的实验研究

高脂血症是动脉粥样硬化的主要危险因素之一，其中sLDL是动脉粥样硬化的独立的危险因素，较1LDL具有更强的致动脉粥样硬化作用。对于难治性特别是家族性高脂血症，药物治疗少有疗效，血液灌流吸附治疗是目前推荐的治疗方法。为此，本研究以纤维素为载体，以磺酸基 胆固醇的双亲基团为配基首次合成了双亲型吸附剂，分别经体外吸附和体内动物灌流实验，检测吸附剂的吸附量。结果显示：双亲纤维素-5吸附剂对LDL、TC、TG有较好的清除作用，对HDL无明显的影响，而且可以改变LDL的分布谱，降低sLDL的百分含量，具有良好的选择件。     

新型亲和吸附剂对血液中循环免疫复合物吸附性能的研究

从５种亲和吸附占筛选出病理性循环免疫复合物具有特异性的吸附的吸附剂，测定其比表面积、孔结构参数：平均孔径、孔容、并讨论了吸附诸条件对ＣＩＣ吸附性能的影响。     

Immobilization of sodium alginate sulfates on polysulfone ultrafiltration membranes for selective adsorption of low-density lipoprotein

A novel method for the immobilization of sodium alginate sulfates (SAS) on polysulfone (PSu) ultrafiltration membranes to achieve selective adsorption of low-density lipoprotein (LDL) was developed, which involved the photoinduced graft polymerization of acrylamide on the membrane and the Hofmann rearrangement reaction of grafted acrylamide followed by chemical binding of SAS with glutaraldehyde. The surface modification processes were confirmed by attenuated total reflectance Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy characterization. Zeta potential and water contact angle measurements were performed to investigate the surface charge and wettability of the membranes. An enzyme-linked immunosorbent assay was used to measure the binding of LDL on plain and modified PSu membranes. It was found that the PSu membrane immobilized with sodium alginate sulfates (PSu-SAS) greatly enhanced the selective adsorption of LDL from protein solutions and the absorbed LDL could be easily eluted with sodium chloride solution, indicating a specific and reversible binding of LDL to SAS, mainly driven by electrostatic forces. Furthermore, the PSu-SAS membrane showed good blood compatibility as examined by platelet adhesion. The results suggest that the PSu-SAS membranes are promising for application in simultaneous hemodialysis and LDL apheresis therapy.