Preparation And Evaluation Of Bilirubin Adsorbents

Bilirubin is a yellow-orange bile pigment.High level of bilirubin can result in Hyperbilirubinemia,which is harmful to health.In clinical,medicine and phototherapy are usually applied for mild cases,especially newborn infants.But for severe ones,blood purification technology must be adopted to save their lives. Hemoperfusion,a kind of blood purification methods,is demonstrating its advantages in the treating hyperbilirubinemia and attracts more and more people's attentions. And key factor of hemoperfusion is the adsorbent.Though some products have been adopted in clinical,security and efficacy both need to be elevated.The objective of my dissertation is to prepare kinds of adsorbents,which are suitable in clinical application for bilirubin removal and possessing high specificity,large adsorptive capacity,and good biocompatibility.There are five parts in this dissertation.The first part is an introduction about basic knowledge of bilirubin, hyperbilirubinemia,the harmfulness and reasons of hyperbilirubinemia and methods for treatment.It also summarizes the blood purification technology and adsorbents utilized in processes of hemoperfusion.And it also chiefly gives an overview of the researches and applications of adsorbents for hyperbilirubinemia.At last,I propose the relative work in this research.The second part is about adsorbents with cellulose as support.First we prepared cellulose microspheres,and then immobilized 8 kinds of amination agents to obtain corresponding adsorbents and carried out vitro test.Results show that it is cel-HDA has the best adsorption performance,and adsorption percentage is 82%to bilirubin solution.The third part is about adsorbents with chitosan as carrier.Under the optimum active condition,we prepared adsorbents immobilized 8 kinds of amination agents and carried out vitro tests on them.Results still show that it is CS-HDA has the best adsorption performance.Meanwhile chitosan adsorbents' performances improve significantly compared with cellulose ones,which means chitosan is a good support for bilirubin adsorbents.The fourth part is about adsorbents with polyvinyl alcohol(PVA)as support.First PVA microspheres are produced as support by suspension polymerization in aqueous medium.Then we research its physical characterizations,and all of them indicate PVA particles are carrier matrix.Second we obtained the max amino group content, 175umol/ml.Under the optimum active condition,we prepared corresponding adsorbents with a series of amination agents and carry out vitro tests on them.Results show adsorbents of PVA-TMA,PVA-TEA and PVA-HDA have the good adsorption performances,with adsorption percentages higher than 80%and maximum capacity up to 4.3mg/ml.Adsorption dynamics curves show this kind of adsorbents have high adsorption velocity and large capacities for they can achieve equilibrium in 0.5h and get 80%of the maximum percentages.In vitro adsorption performance evaluations show their adsorption capacities are respectively 1.577mg/ml,1.584mg/ml and 1.784mg/ml,while volume ratio of adsorbent to bilirubin simulating serum solution is 10:1.We also inspected their performances to human plasma.PVA-HDA's maximum adsorption percentage is 50%without obvious adsorption to other components,while volume ratio is 5:1.All results indicate adsorbents have good performances,large adsorption capacities,good selectivity and biocompatibility.There will be a prospect of clinical application.The last part is the summary of the whole dissertation.It summarizes all the work and achievements,points out the new ideas and fingers out the work in next step.