交联透明质素特性的研究

目的 研究交联透明质素的特征和性能,为其应用于临床提供理论依据.方法 采用扫描电镜-能谱仪分析交联透明质素的化学成分.采用傅立叶变换红外光谱法对交联透明质素结构进行分析.使用旋转流变仪测定交联透明质素凝胶的储能模量、耗能模量及粘度等流变学性能的动态变化.采用激光粒度仪测定凝胶中微粒的大小及分布.结果 能谱分析显示交联透明质素中主要成分与天然透明质素相同,但多了硫原子,该元素来自交联剂.红外光谱测定显示,交联透明质素的吸收特征基本与未交联透明质素相似,只是在示硫砜键振动的吸收加强.交联透明质素凝胶的储能模量、耗能模量显著高于天然透明质素凝胶,与频率的依赖性不明显,表现为强凝胶弹性体特征,凝胶微粒平均粒径约为500 μm.结论 交联透明质素是天然透明质素与二乙烯基砜交联反应形成的多聚物,该多聚物溶胀于水后生成水不溶性凝胶.交联透明质素微粒凝胶制剂具有稳定性好和粘弹性高等优点,有利于进一步拓展其临床应用.     

环氧化合物交联明胶水凝胶的制备及表征

目的明胶水凝胶因其良好的生物相容性而成为一种应用前景很好的组织工程材料。该研究采用不同浓度的明胶,添加了适量的环氧化合物交联剂聚乙二醇二缩水甘油醚(PGDE),制备了不同的明胶水凝胶。红外光谱显示,PGDE以两端开环的方式交联到了明胶分子上。随着明胶和交联剂浓度的增大,水凝胶的溶胀率从1218.19%下降到525.23%,最大压缩应力显著增大,从27.64 kPa增大到113.20 kPa,压缩正切模量也从0.19 kPa增大到0.59 kPa,力学性能得到了明显提高。PGDE交联明胶水凝胶具有优异的弹性回复性能,弹性回复率最高可达98.03%。溶血率试验结果表明,凝胶有良好的血液相容性。     

阳离子多聚物纳米基因载体系统的研究进展

阳离子多聚物能与DNA通过静电吸附作用而自组装成纳米微粒，保护DNA防止被核酸酶降解。阳离子多聚物由于具有合成简便、储存稳定、目的基因容量大、特异靶向性强、免疫原性低等优点被用作非病毒基因载体。阳离子多聚物按特性可分为两类：人工合成型和天然生物型。常见的人工合成型阳离子多聚物基因载体主要有：多聚左旋赖氨酸[poly(L-Iysine)，PLL]，多聚乙烯亚胺(polyethyIenimine，PEI)和星状树突体[PnIyamidnamine(PAMAM)dendrimers]等：天然生物型阳离子多聚物基因载体主要有壳聚糖及其衍生物和明胶等。本文重点讨论了阳离子多聚物介导的基因导入细胞机理和基因进行靶向性转移的策略，详细论述了各种阳离子多聚物用作基因载体的性能特点，最后对非病毒基因载体的发展作出展望。     

纳米羟基磷灰石/阿司匹林/聚乙烯醇/明胶/海藻酸钠水凝胶支架的制备与表征

背景：阿司匹林是经典非类固醇抗炎药物,合适剂量的阿司匹林可调节免疫、促进成骨。制备出可缓释阿司匹林、调控骨缺损区免疫微环境和加速骨缺损修复的骨组织工程材料是目前的研究热点。目的：制备可调控免疫微环境和加速骨缺损修复的新型水凝胶支架。方法：制备含有质量分数0%,10%和20%纳米羟基磷灰石的纳米羟基磷灰石/阿司匹林/聚乙烯醇/明胶/海藻酸钠水凝胶支架,对水凝胶支架的微观结构、孔隙率、化学成分、晶相结构、药物缓释性能、力学性能、溶胀性能和降解性能进行表征。通过细胞增殖和细胞毒性实验评价水凝胶支架的生物相容性。结果与结论：(1)扫描电镜和孔隙率检测结果表明,0%,10%纳米羟基磷灰石组水凝胶支架具有更仿生的层级多孔结构、孔隙通联性和孔隙率;(2)傅里叶红外光谱和X射线衍射结果表明,水凝胶支架内各原料以物理、化学双交联方式结合,且不会破坏纳米羟基磷灰石的晶相结构;(3)力学性能结果表明,10%纳米羟基磷灰石组水凝胶支架具有最佳的压缩模量和压缩强度;(4)药物释放性能结果显示,随着纳米羟基磷灰石质量的增加,水凝胶支架的阿司匹林累计释放率降低,但是药物突释率降低、缓释时间延长;(5)溶胀性能和降解...     

气相色谱法检测交联透明质酸中交联剂残留量

目的建立一种二乙烯基砜交联透明质酸中交联剂二乙烯基砜残留量的检测方法.方法采用气相色谱法检测二乙烯基砜残留量,色谱柱为HP-5毛细管色谱柱(Agilent 19091J-413:325℃:30m×320μm×0.25 μm),程序升温,采用FID检测器,载气为氮气.结果二乙烯基砜在1μg～50μg/g线性关系良好,线性相关系数r=0.9999,平均回收率为97.8%(RSD为2.6%,n=5).结论气相检测交联透明质酸中交联剂含量,结果准确,方法简单可靠,可用于交联透明质酸水凝胶产品质量控制.     

不同交联密度甲基丙烯酰酯明胶/脱细胞半月板细胞外基质复合水凝胶的性能

文题释义：脱细胞半月板细胞外基质：由新鲜半月板组织通过湿法差速离心方法脱细胞制备而来,在去除了异体半月板的免疫原性的同时,仍保留了组织的大部分成分和组织本身的生物学性能,例如影响细胞的活性、调控细胞的增殖和分化、促进组织再生和修复等。 甲基丙烯酰酯明胶：是一种明胶的衍生物,由甲基丙烯酸酐与明胶合成而来。在加入光引发剂的基础上经紫外线照射,明胶链上的甲基丙烯酰胺和甲基丙烯酸甲酯侧基聚合形成聚合物链,聚合物链交错纵横,最终形成网状结构。 交联密度：通常用来表征交联聚合物里交联键的数量,主要受交联时间和交联光强度的影响,其可明显改变聚合物链的形成情况。 背景：交联后的聚合物链对水凝胶的基本性质和细胞相容性存在显著影响,而交联密度可明显改变聚合物链的形成情况,有关交联密度对水凝胶性能影响的针对性研究较少。 目的：制备一种细胞相容良好性的复合水凝胶,探究交联密度对该水凝胶性能的影响。 方法：配制甲基丙烯酰酯明胶溶液,然后加入脱细胞半月板细胞外基质溶液与LAP溶液,制备预凝胶溶液,采用蓝光对溶液进行交联,交联时间分别为10,30,60 s,检测3种水凝胶的压缩弹性模量、溶胀倍率与降解性能。将半月板纤维软骨细胞加入预凝胶溶液中,采用蓝光对溶液进行交联,交联时间分别为10,30,60 s,检测培养对应时间的细胞活性、形态与聚集。 结果与结论：①交联60 s水凝胶的压缩模明显高于交联10,30 s的水凝胶(P < 0.05);②交联10 s水凝胶的溶胀倍率明显高于交联30,60 s的水凝胶(P < 0.05),交联30,60 s的水凝胶的溶胀倍率比较差异无显著性意义(P > 0.05);③随着交联时间的延长,水凝胶的降解时间延长,交联60 s的水凝胶需要80 min完全降解,交联10 s的水凝胶50 min就可以完全降解;④培养24 h后,3组水凝胶中的细胞活性均在95%以上,各组之间无差异(P > 0.05);⑤培养1 d时,3组水凝胶中的细胞均呈球形且均匀分布;4 d时,3组细胞均开始伸展,交联10 s水凝胶中有较小的细胞团;7 d时,3组细胞树突状伸展更为明显,其中交联10 s水凝胶中形成了较为明显的细胞团;⑥培养1,7,14 d时,交联10 s水凝胶中的细胞活性均在85%以上。培养1 d时,交联10 s水凝胶中的细胞呈球形分布,且分布均匀;培养28 d时,细胞呈树突状伸展,并聚集形成网状结构;⑦结果表明,甲基丙烯酰酯明胶/脱细胞半月板细胞外基质复合水凝胶的性能可通过调整交联密度进行优化。 ORCID: 0000-0002-3606-1097(周建) 中国组织工程研究杂志出版内容重点：生物材料;骨生物材料; 口腔生物材料; 纳米材料; 缓释材料; 材料相容性;组织工程     

可注射封闭性水凝胶力学性质与其止血性能的相关性

目的探究封闭性水凝胶力学性质与其止血性能之间的关系。方法通过测量透明质酸/明胶水凝胶凝固时间、弹性模量、黏性模量、顶破强度和止血性能,与医用纤维蛋白胶止血剂对比,提出凝固时间和力学参数,用于判断封闭性水凝胶应用于临床止血的可行性。结果凝固时间长以及弹性模量、黏性模量和顶破强度小的水凝胶只可能对小出血量起控制作用,凝固时间短、弹性模量、黏性模量和顶破强度大的水凝胶能有效减少大出血量情况下的血液损失。结论水凝胶的凝固时间、弹性模量、黏性模量以及顶破强度与其止血性能有关,如果水凝胶封闭止血要达到纤维蛋白胶的止血水平,其凝固时间应小于120 s,弹性模量大于600 Pa,黏性模量大于120 Pa;对于直径2 mm的组织模型破损,顶破强度要不低于10.7 kPa,最好高于16.0 kPa。     

力学性能可控的甲基丙烯酸化明胶（GelMA）人工软骨性能及软骨/骨表界面结合研究

目的 探寻优化骨表面力学匹配的软骨修复材料,并探讨软骨修复材料与骨结合的表界面性能,为软骨修复材料的设计及制备提供依据。方法 以明胶和甲基丙烯酸酐为原料,在明胶分子中引入双键结构,使用紫外光交联的方式制备甲基丙烯酸化明胶（GelMA）水凝胶。运用扫描电子显微镜、万能力学试验机分析水凝胶的形貌、孔径大小和力学性能;体外降解实验、体外拉伸实验评估水凝胶的降解和拉伸特性;黏附能力定性实验、三维立体光学显微镜和扫描电子显微镜评估水凝胶的黏附能力;细胞增殖测试和Live/Dead染色测定细胞活性和毒性。探讨了不同紫外光照时间下GelMA水凝胶的理化性能及软骨/骨材料结合的表界面结合性能,对性能适宜的修复材料进行了配比、力学优化。结果 紫外光照（UV）交联时间为1 min时水凝胶孔隙最大（110.25±6.51）μm,孔隙率高达（45.24±2.78）%;12 h时水凝胶的平衡溶胀比达（148.43±3.84）%;28 d失重率为（17.40±2.38）wt%;水凝胶的拉伸性能随紫外光照时间延长而逐渐增加;GelMA水凝胶对骨髓间充质干细胞增殖无明显抑制作用;水凝胶软骨修复材料与骨的结合良好,可黏附于仿生骨材料表面。结论 紫外光照交联时间1 min时GelMA水凝胶的吸水速率和平衡溶胀比最佳,降解速快,拉伸性能与天然软骨结构类似,具有良好的生物相容性,与骨修复材料力学匹配,该力学性能可控的GelMA水凝胶软骨修复材料为软骨/骨的连接及性能匹配提供了依据。     

修复脊髓损伤的仿生多孔水凝胶的制备研究

目的水凝胶是含水量高和体表面积大的化学性惰性合成高分子,当植入到脊髓组织中,为细胞和轴突提供力学支持。本研究对修复脊髓损伤水凝胶制备、物理特性进行研究。方法本研究交联的水凝胶由2-甲基丙烯酸羟（HEMA）．2乙基三甲基氯化物（methacryloyloxy,MOETACL）共聚物合成。利用氯化钠（NaCl）微粒制备水凝胶的孔隙,用扫描电子显微镜观察其结构。结果计算水凝胶在单位体积上的孔隙数,孔的平均直径和平均体积。以HEMA．MOETACL为基础的水凝胶在其组成上具有显著特征。结论均质多孔的水凝胶,其在修复脊髓损伤的生物特性上具有显著特征。     

超快动态交联的可注射壳聚糖-透明质酸水凝胶及促创伤愈合研究

可注射动态水凝胶是近年研究的热点,而制备无催化剂体系的快速交联的可注射动态水凝胶是研究的难点之一。以甲基丙烯酰化壳聚糖(CHMA)和醛基化透明质酸(ALHA)为原料,利用CHMA分子上的氨基与ALHA分子上的醛基和羧基,分别形成可逆动态席夫碱键和静电相互作用,可快速制备一种水凝胶。通过动态流变分析仪表征其凝胶化速率、剪切变稀行为和自愈合特征,通过体外细胞三维培养实验评估其细胞相容性,并通过急性全层皮肤创伤修复实验对其创伤愈合速率进行评估。结果表明,只需5 s,CHMA和ALHA的混合溶液就能形成凝胶。此外,该凝胶具有剪切变稀和快速自愈合的可注射特征,当扫描频率从10^-1 s^-1增加至10² s^-1时,其复数黏度由0.4 kPa降低至8 Pa;当应变在1%~1000%之间交替变化时,储能模量与损耗模量的大小能够迅速切换,且模量没有显著性地降低。同时,体外细胞三维培养实验表明,该水凝胶还具有优异的细胞相容性(细胞存活率高于95%),并且在雄性ICR小鼠急性全层皮肤缺损模型实验中,水凝胶组的创伤愈合时间相比空白对照组缩短5～7 d,表现出较快的创伤愈合速率。综上可见,这种可注射壳聚糖-透明质酸水凝胶在生物医药、组织功能、临床医学等领域具有广阔的应用前景。     

In vivo performance of two different hydroxyapatite coatings on titanium prepared by discharging in electrolytes

This study reports a discharging method for bone-like carbonated HA (cHA)-coating (Ca/P 1.71) and stoichiometric HA (sHA)-coating (Ca/P 1.67) with micrometer order thicknesses on titanium plates, using modified body fluid and acidic calcium phosphate solutions, respectively. In vivo histological performance of the HA coatings prepared by discharging in electrolytes was evaluated. Bone-contact indexes of HA coatings were measured microscopically. Additionally, bone-coating interface was analyzed by scanning electron microscopy and the use of an electron probe microanalyzer. Results demonstrated that there was no significant difference in contact index between HA coatings. However, the cHA coating was practically replaced by immature bone, and the titanium metal substrate was directly connected to the bone structure whereas the sHA coating layer remained and was partially detached from the titanium metal substrate. Since detached coating particles are pathogens, and can cause peri-implantitis, the cHA coating was more favorable than the sHA coating even if contact index was equivalent to that of the sHA coating. It is thought that coating thickness and chemical composition of coatings are important for biological stability of implants. In conclusion, since bone-like thin cHA coating showed high osteoconductivity and bone replacement, bone-like HA is superior to sHA coating for use in dental implants.     

不同剂量配比的实验性甲型肝炎戊型肝炎联合疫苗的免疫原性研究

目的研究实验性甲型肝炎(甲肝)戊型肝炎(戊肝)联合疫苗的免疫原性,探讨两种抗原组分间的相互作用。方法制备9种不同剂量配比的实验性甲戊肝联合疫苗,与单价疫苗对照一起免疫15组(共120只)小鼠,定时采血,以ELISA和中和试验检测抗HAV和抗HEV的抗体。结果高剂量的HAV抗原(5×105U/L)与不同剂量的HEV抗原(200、100、50mg/L)配制的联合疫苗,诱导的抗HAV中和抗体的滴度可达1∶1024,含25×104、125×103U/LHAV抗原的联合疫苗诱导的中和抗体滴度为1∶512,不同剂量的HEV抗原对抗HAV中和抗体的产生均无明显影响。与单价戊肝疫苗相比较,联合疫苗诱导的抗HEV抗体水平均有明显升高,且随联合疫苗中HAV抗原的含量(5×105、25×104、125×103U/L)的增加而升高,HEV抗原的剂量在一定范围内(200、100、50mg/L)与抗HEV抗体产生无明显关系。采用基于逆转录套式PCR的中和试验表明,各联合疫苗组的免疫血清均可中和HEV。结论实验性甲、戊肝联合疫苗内HAV抗原对HEV抗原的免疫原性具有增强作用,而HEV抗原对HAV抗原的免疫原性无明显影响。     

Synthesis and characterization of a novel hyaluronic acid hydrogel

Hyaluronic acid (hyaluronan, HA) has many medical applications as a biomaterial. To enhance its biostability, a novel hydrogel of cross-linked hyaluronic acid was prepared using a double cross-linking process, which involves building cross-linkages between hydroxyl group pairs and carboxyl group pairs. The present study explored a number of cross-linking processes in order to obtain different degrees of cross-linking, which were evaluated by the measurement of water absorption capacity as an index of the gel network density. To gain a better understanding of the stability of the gel, the chemical structure and particularly the rheological behaviour of the cross-linked HA, which included the influences of factors, such as degree of cross-linking, HA concentration and gel particle size, were investigated. The in vitro biostability against hyaluronidase and free radical degradation was tested to show that the cross-linked hydrogel had improved resistance to in vitro hyaluronidase and free radical degradation.     

Synthesis and characterization of a novel hyaluronic acid hydrogel

Hyaluronic acid (hyaluronan, HA) has many medical applications as a biomaterial. To enhance its biostability, a novel hydrogel of cross-linked hyaluronic acid was prepared using a double cross-linking process, which involves building cross-linkages between hydroxyl group pairs and carboxyl group pairs. The present study explored a number of cross-linking processes in order to obtain different degrees of cross-linking, which were evaluated by the measurement of water absorption capacity as an index of the gel network density. To gain a better understanding of the stability of the gel, the chemical structure and particularly the rheological behaviour of the cross-linked HA, which included the influences of factors, such as degree of cross-linking, HA concentration and gel particle size, were investigated. The in vitro biostability against hyaluronidase and free radical degradation was tested to show that the cross-linked hydrogel had improved resistance to in vitro hyaluronidase and free radical degradation.     

Carbodiimide cross-linked hyaluronic acid hydrogels as cell sheet delivery vehicles: characterization and interaction with corneal endothelial cells

It was reported that cell-adhesive gelatin discs have been successfully used as delivery vehicles for intraocular grafting of bioengineered corneal endothelial cell sheets. Development of alternative biomaterials to bovine-based gelatin vehicles can potentially eliminate the risk of bovine spongiform encephalopathy. In the present work, to investigate whether it was appropriate for use as cell sheet delivery vehicles, 1-ethyl-3-(3-dimethyl aminopropyl) carbodiimide (EDC) cross-linked hyaluronic acid (HA) hydrogels were studied by determinations of morphological characteristic, mechanical and thermal property, water content, in vitro degradability and cytocompatibility. Glutaraldehyde (GTA) cross-linked HA samples were used for comparison. It was found that HA discs after cross-linking significantly increased its tensile stress but reduced its tensile strain, water uptake and enzymatic degradability. The results of differential scanning calorimetry demonstrated that cross-linking could lead to the alteration of polymer structure. In addition, the EDC-cross-linked HA discs had a smoother surface structure, a faster degradation rate and a relatively lower cytotoxicity as compared to the GTA cross-linked counterparts. It is concluded that EDC can be successfully applied for HA cross-linking to fabricate structurally stable, mechanically reinforced, readily deformable, transparent and cytocompatible HA hydrogel discs with the potential to be applied as delivery vehicles for corneal endothelial cell therapy.     

Fabrication and characterization of porous hyaluronic acid-collagen composite scaffolds

Hyaluronic acid (HA) plays a vital role in many tissues, influencing water content and mechanical function, and has been shown to have positive biological effects on cell behavior in vitro. To begin to determine whether these benefits can be accessed if HA is incorporated into collagen-based scaffolds for tissue engineering, HA-collagen composite matrices were prepared and selected properties evaluated. HA-collagen scaffolds were cross-linked with carbodiimide and loss rates of HA in culture medium assessed. Scaffold pore structures were evaluated by light and electron microscopy. Adult canine chondrocytes were grown in selected HA-collagen scaffolds to assess the effects of HA on cell behavior. Homogenous HA-collagen slurries were achieved when polyionic complexes were suppressed. HA was uniformly distributed through the scaffolds, which demonstrated honeycomb-like pores with interconnectivity among pores increasing as HA content increased. Virtually all of the HA added to the collagen slurry was incorporated into the composite scaffolds that underwent a 7-day cross-linking protocol. After 5 days in culture medium, the HA content in the scaffolds was 5-7% regardless of initial HA loading. After only 2 weeks in culture cartilaginous tissue was found in the chondrocyte-seeded HA-collagen scaffolds. This study contributes to the understanding of the effects of HA content, pH, and cross-link treatment on pore characteristics and degradation behavior essential for the design of HA-collagen scaffolds. The demonstration that these scaffolds can be populated by chondrocytes and support in vitro formation of cartilaginous tissue warrants further investigation of this material system for tissue engineering.     

Synthesis and characterization of hyaluronic acid–poly(ethylene glycol) hydrogels via Michael addition: An injectable biomaterial for cartilage repair

Injectable hydrogels based on hyaluronic acid (HA) and poly(ethylene glycol) (PEG) were designed as biodegradable matrices for cartilage tissue engineering. Solutions of HA conjugates containing thiol functional groups (HA-SH) and PEG vinylsulfone (PEG-VS) macromers were cross-linked via Michael addition to form a three-dimensional network under physiological conditions. Gelation times varied from 14 min to less than 1 min, depending on the molecular weights of HA-SH and PEG-VS, degree of substitution (DS) of HA-SH and total polymer concentration. When the polymer concentration was increased from 2% to 6% (w/v) in the presence of 100 U ml^?1 hyaluronidase the degradation time increased from 3 to 15 days. Hydrogels with a homogeneous distribution of cells were obtained when chondrocytes were mixed with the precursor solutions. Culturing cell–hydrogel constructs prepared from HA185k-SH with a DS of 28 and cross-linked with PEG5k-4VS for 3 weeks in vitro revealed that the cells were viable and that cell division took place. Gel–cell matrices degraded in approximately 3 weeks, as shown by a significant decrease in dry gel mass. At day 21 glycosaminoglycans and collagen type II were found to have accumulated in hydrogels. These results indicate that these injectable hydrogels have a high potential for cartilage tissue engineering.     

Cross-linked hyaluronate hydrogel prevents adhesion formation and reformation in mouse uterine horn model

The aim of this study was to evaluate the efficacy of cross-linked hyaluronate hydrogel (HA gel) as an adjuvant for postoperative adhesion prevention, in a mouse uterine horn model. In experiment 1 uterine horns were abrased with iodine. HA gel was applied to the injured surface before closure in the treatment group. In experiment 2, after injuring the uterine horns, three stitches were placed at equal distances around the uterine horns to appose the injured medial surfaces of the two horns during healing. HA gel was inserted between the uterine horns in the treatment group. In experiment 3 prevention of adhesion reformation was assessed. After lysis of adhesions that were induced as in experiment 2, HA gel was introduced between the serosal surfaces of apposing uterine horns. Untreated animals served as controls in each experiment. Statistical analysis was carried out using Student's t-test. The adhesion score was significantly lower in the HA gel group on the 14th day compared with controls in all the experiments: in experiment 1, 0.3 +/- 0.4 versus 1.7 +/- 1.2; in experiment 2, 0.9 +/- 1.0 versus 2.6 +/- 0.5; and in experiment 3, 1.5 +/- 0.9 versus 2.2 +/- 0.6 respectively. Cross-linked HA gel significantly reduced de-novo adhesions (P< 0.03) and adhesion reformation (P < 0.03).     

Chemical cross-linking of proteins of the influenza virion

Purified influenza virus (A/FPV/Rostock/34;H7N1) was exposed briefly to pH 5 before returning to an alkaline pH. Virus was then reacted with one of three chemical cross-linking reagents [dimethyl suberimidate (DMS), tartryl diazide (TDA), or formaldehyde which span 11, 6, and 2A, respectively]. Cross-linked polypeptides were analysed by SDS-polyacrylamide gel electrophoresis under reducing conditions and identified with monospecific antisera against HA1, HA2, NP and M1. Acidification resulted in changes in the cross-linking patterns for both HA1 and HA2 which could be detected with all three reagents. Most notable were the data with formaldehyde: under alkaline conditions cross-linking gave only HA1:HA2 heteropolymers but after brief acidification none of these were formed and in their place was a novel HA1 homodimer, an HA2 homotrimer and an HA2 of Mr 50k cross-linked to form a homodimer with another HA2 or to a heterodimer with M1. Although cross-linking by formaldehyde was much more affected by acidification of the virus than cross-linking by DMS or TDA, over half the polymers cross-linked by DMS were no longer formed after acidification. The patterns of cross-linking of NP and M1 were unchanged by low pH treatment.     

Adsorptive separation of hemoglobin by molecularly imprinted chitosan beads

A simply hemoglobin (Hb) molecularly imprinted polymer (MIP) was prepared using Hb as the imprinted molecule, acrylamide as the functional monomer and cross-linked chitosan beads as the supporting matrix. The MIP was achieved by entrapment of the selective soft polyacrylamide gel in the pores of the cross-linked chitosan beads by letting acrylamide monomer and the protein diffuse into the pores of chitosan beads before starting the polymerization. The chitosan beads were freed from the surrounding polyacrylamide gel by washing. The Langmuir and Freundlich adsorption models were applied to describe the equilibrium isotherms. Langmuir analysis showed that an equal class of adsorption was formed in the MIP and the adsorption equilibrium constant and the maximum adsorption capacity were evaluated. The MIP has much higher adsorption capacity for Hb than the non-imprinted polymer with the same chemical composition, and the MIP also has a higher selectivity for the imprinted molecule. The MIP can be reused in an easy way and the reproduction coefficient was approximately 100% at low concentration.