以壳聚糖为载体的内毒素吸附剂

内毒素血症(Endotoxemia)可出现于多种疾病过程中,导致器官坏死、不可逆休克和死亡。如何及时并有效地清除患者体内的内毒素,是临床医学面临的一个难题．选用高效吸附剂,籍助血液灌流的方法从血液中直接清除内毒素,受到了人们越来越多的关注。     

以氨基酸为配体的血液灌流用内毒素吸附剂的制备及性能研究

以琼脂凝胶为载体,氨基酸为配体,合成了内毒素吸附剂,并对其吸附效果进行了比较.对吸附剂的各种性质进行了表征,选取琼脂-赖氨酸吸附剂对内毒素血症的兔子进行血液灌流,可将血浆中的内毒素降至接近正常值,最高清除率达73.6%,且吸附剂具有良好的血液相容性.     

以赖氨酸为配基的内毒素吸附剂的研究

内毒素血症可出现于多种疾病中,如大面积烧伤、重症肝炎、肝硬化等疾病,使机体免疫功能严重受损,引起多器官功能衰竭等一系列严重的病理变化,最终导致不可逆休克和死亡,在美国每年都有超过10万人死于此病,临床上尚无有效的治疗方法,因此,及时、有效地清除或破坏患者体内的内毒素,     

治疗内毒素血症的研究进展和现状

本文简述了内毒素,内毒素的吸收途径、对机体的生物学效应及器官对内毒素的消除作用以及近年来内毒素血症的治疗概况,并对治疗内毒素血症的新方法进行了展望。     

细菌内毒素分析检测研究进展

细菌内毒素是造成临床脓毒血症及多器官衰竭的关键毒力因子。微量的内毒素就可以导致生物体发热，产生炎症、组织损伤，甚至死亡。因此，高灵敏度和准确度的内毒素分析检测技术，在食品、环境、医药、畜禽养殖及内毒素研究领域具有重要意义。本文介绍了细菌内毒素的结构和主要性质，总结了内毒素的生物学检测方法，综述了基于色谱-质谱联用等技术在内毒素检测中的研究进展，最后对内毒素分析发展趋势和应用进行了展望。     

基于生物传感器的内毒素检测研究进展

内毒素是造成内毒素血症、多器官功能衰竭的关键因子,对人体健康存在着严重的危害。发展高选择性、高灵敏度、快捷便携且不受现场限制的检测方法具有重要意义。生物传感器以其高效、灵敏、易于自动化和微型化等优点,在相关检测领域中显示出重要的研究价值和巨大的发展空间。本文简要介绍了近年来内毒素的常用检测方法,重点综述了光学生物传感器和电化学生物传感器在内毒素检测应用中的研究进展。对生物传感器在内毒素检测中面临的挑战及其发展趋势进行了讨论和展望。     

内毒素的去除策略

革兰氏阴性菌的致病性以及革兰氏阴性菌脓毒血症时出现的毒性表现是与牢固结合在其细菌外膜中的一种大分子物质即内毒素密切相关的,文章主要介绍了内毒素的本质和它的危害,并根据该课题组在此领域多年的研究经验,介绍了内毒素的去除策略。     

乳化液膜清除未结合胆红素

高未结合胆红素症 (Ｈｙｐｅｒｂｉｌｉｒｕｂｉｎｅｍｉａ)是新生儿常见疾病 .胆红素在血液中的浓度过高 ,会伤害婴儿的大脑 (核黄疸 ) [1].肝昏迷患者的症状与胆红素在血液中含量过高也有直接关系 ,迅速有效地将其清除可使患者症状缓解[2 ],迄今为止 ,清除胆红素的研究主要集中在以吸附剂吸附为基础的血液灌流方法 ,所用的吸附剂主要有活性炭和大孔吸附树脂 ,活性炭的吸附选择性和血液相容性都比较差 ;大孔吸附树脂的吸附选择性和血液相容性等方面有待进一步提高[3],特别是在吸附未结合胆红素时 ,清除率低、清除速度慢 ,难以满足临床方面…     

以聚乙烯基咪唑为配基的内毒素亲和吸附剂的研究

通过乙烯基咪唑(VI)在硅胶粒子表面的自由基接枝聚合制备了一种以聚乙烯基咪唑为配基的新型内毒素亲和吸附剂. 用FTIR检测样品中咪唑基的特征吸收, 用热重分析法(TGA)测定了PVI的接枝率. 实验发现, PVI在吸附剂中的含量对内毒素的吸附率影响很大. 当PVI的接枝率为2.5％左右时, 吸附剂对内毒素的去除率最大. 在离子强度小于1 mol/L和pH=7的中性条件下, PVI吸附剂对内毒素具有最佳的吸附性能. 该吸附剂具有良好的血液相容性. 内毒素在该亲和吸附剂上的吸附等温线符合Freundlich吸附方程, 其吸附动力学为二级反应.     

吸附剂结构的计算机辅助设计及吸附机理

以琼脂糖凝胶为载体, 二甲胺为配体, 制备了β-OH, γ-OH和β-SH吸附剂. 通过对水相中内毒素的动、静态吸附探索有效的吸附剂结构. 研究结果显示, 吸附剂对内毒素的清除率随配体结构的不同呈现出较大差异, 其中β-OH吸附剂的清除效果最好, 达到90.7%. 运用计算机模拟方法提出了β-OH吸附剂与内毒素作用的模型, 阐明静电力是影响吸附性能的主要因素, 同时氢键的协同和空间位阻效应也不可忽视.     

计算机模拟内毒素吸附剂吸附机理的研究

应用计算机模拟的方法研究了内毒素吸附剂的吸附机理. 模拟结果显示, 以二甲胺为配体的吸附剂, 当β位存在羟基时, 此羟基可与内毒素分子间形成氢键, 并形成一个八元环的稳定结构. 此时吸附剂与内毒素之间存在静电、 氢键、 疏水相互作用和八元环的协同作用. 同时模拟了羟基位于配体不同位置的吸附剂与内毒素的相互作用. 结果表明, 静电作用为主要的相互作用力, 羟基的位置对吸附剂的吸附能力影响显著.     

ADSORPTION OF PHENOLIC COMPOUNDS ONTO THE SPHERICAL MACROPOROUS ADSORBENT BASED ON UREA-FORMALDEHYDE CONDENSED POLYMER

INTRODUCTIONAdsorption separation process may be advantageous compared to the conventionally usedmethod based on organic solvent extraction due to its low energy consumption, convenientoperation and high concentrating ability [11. Currently, however, the ability of the commerciallyavailable adsorbentS to selectively adsorb one solute or even families of compounds with similarchemical structUre from a complex system such as the extraction solUtion of Chinese herbalmedicines is limited and…     

ADSORPTION OF PHENOLIC COMPOUNDS ONTO THE SPHERICAL MACROPOROUS ADSORBENT BASED ON UREA—FORMALDEHYDE CONDENSED POLYMER

Adsorption of phenol,catechol and resorcinol,which vary in their ability to interact with the adsorbent through hydrogen bond,were used to investigate the adsorption mechanistic interaction.The adsorption enthalpies of the above mentioned compound onto the adsorbent were calculated and thermodynamic analysis was carried out.The results showed the adsorbent with the lowest adsorption enthalpies for the sorbate such as catechol with intermolecular hydrogen bond also display the lowest adsorption affinity.On the other hand,the more of the groups available for hydrogen bond interaction,the higher of the adsorption affinity.These observations support the contention that phenol adsorption is driven predominantly by specific interaction of the solute with active sites on the surface of the adsorbent.     

Removal of endotoxin from culture supernatant of Bordetella pertussis with aminated poly(gamma-methyl L-glutamate) spherical beads.

Attempts were made to prepare adsorbents having a high affinity for endotoxin in the culture supernatant of Bordetella pertussis. When poly(gamma-methyl L-glutamate) (PMLG) was used as a matrix and amino groups as the ligand, the highest affinity for endotoxin was attained even at a high ionic strength (mu = 0.2-0.4). PMLG beads containing amino groups of about 3.2 meq/g selectively removed endotoxin from the culture supernatant of B. pertussis without affecting the protective antigens. It was demonstrated that 1 ml of the wet adsorbent adsorbed 4.5 mg of endotoxin. The beads of PMLG derivatives, therefore, are considered to be a useful adsorbent for the removal of endotoxin from the pertussis vaccine, affecting neither filamentous hemagglutinin nor pertussis toxin.     

ADSORBENTS USED IN THE CLEARANCE OF ENDOTOXIN

A series of modified poly (methyl methacrylate, PMMA) resins were prepared and compared their adsorption abilities to endotoxin. The results showed that adsorbents, which were grafted with tertiary amine and long spacing arms, had the best adsorption capacities and good blood compatibility, It is hopeful to be used as adsorbent in hemoperfusion for clinical clearance of endotoxin. The influence of original concentration of endotoxin on adsorption and the adsorption mechanism were also investigated.     

ADSORBENTS USED IN THE CLEARANCE OF ENDOTOXIN

1.INTRODUCTION[()-227.3()]Endotoxinislipopolysaccharide(LPS)derivedfromthecellmembranesofgram-negativebacteria.Endotoxincancausefebrilereactionsinanimalswithsymptomsofhighfever,vasodilation,diarrheaandfetalshockwheninjectedeveninaverysmallamount[1].Iftheconcentrationofendotoxininpatients?bloodishighenoughitcancauseseveresepsis,whichisamajorcauseofdeathinpatientsandcontinuestohaveahighmortalitydespiteappropriatesurgery,potentantibiotic,andintensivesupportivetherapy[2~5].LipidAisthemaintox…