用于单克隆抗体纯化的仿生多肽超大孔PGMA微球制备及其性能

以仿生多肽配基FYEILHC为亲和配基、以葡聚糖修饰的聚甲基丙烯酸缩水甘油酯[Dextran-poly(glycidyl methacrylate),Dextran-PGMA]超大孔微球为基质,制备用于单克隆抗体纯化的仿生多肽超大孔PGMA微球,在环氧氯丙烷中滴加2 mol/LNaOH使其表面衍生出环氧基,在表面修饰FYEILHC;用扫描电镜表征微球表面形貌,用AKTA蛋白纯化系统考察了Dextran-PGMA微球和琼脂糖微球对抗体的动态吸附量随线性流速的变化。结果表明,偶联FYEILHC后Dextran-PGMA微球仍能保持其大孔结构,在923cm/h线性流速下,其对抗体的动态吸附量仅下降约8%,而琼脂糖微球的动态吸附量则迅速下降25%。表明在较高流速下,抗体在Dextran-PGMA微球上的传质性能较好。吸附-用0.1mol/LNa OH原位清洗重复40次后,Dextran-PGMA微球对抗体的动态吸附量约为(21±1)mg/mL,表明微球具有良好的化学稳定性;血清中回收的抗体纯度为95.0%,表明仿生多肽亲和介质具有从复杂生物样品中纯化抗体的巨大潜力,可满足高流速、高通量抗体分离纯化需求。

新型电荷型纳米盘的可控制备及其与细胞色素P450的结合性能

分别采用氮气吹干法和旋转蒸发法制备由磷脂和膜支架蛋白组成的电荷型纳米盘,用凝胶过滤色谱对其尺寸分级,分析了其性能,考察了其与肝微粒体细胞色素P450的结合能力。结果表明,纳米盘外观澄清透明,微观呈圆盘状,平均直径10nm,在p H 7.4下Zeta电位为-19.86 m V;肝微粒体破碎液与纳米盘能很好结合,CO差示光谱在450 nm出现明显吸收峰,细胞色素P450含量为0.10 nmol/mg,比活比未经纳米盘处理时提高13.0倍,较传统方法提升1.5倍,且操作时间由数日缩短至数小时。电荷型纳米盘在结合膜蛋白细胞色素P450的同时,活性保持良好,在膜蛋白研究领域极具应用潜力。

新型耐碱蛋白A介质的制备与性能

以蛋白A结构中耐碱性更好的C区为基础,构建一种新型耐碱蛋白A,并偶联至琼脂糖基质,获得新型耐碱蛋白A亲和层析介质,分别用激光共聚焦显微镜和石英晶体微天平研究了人免疫球蛋白(h Ig G)与蛋白A介质的结合过程。结果表明,该介质具有较商品配基更高的结合力和稳定的再生性能,hIgG动态载量达62.0 mg/mL,40次再生操作后载量为初始载量的84%。该介质在抗体纯化领域具有较好的应用前景。

Dynamic mechanical behavior and nonlinear hyper-viscoelastic constitutive model of SiO_(2) particle-reinforced silicone rubber composite:experimental and numerical investigation

SiO_(2)-particle reinforced silicon rubber composite(SP-RSRC)is a widely utilized material that offers shock absorption protection to various engineering structures in impact environments.This paper presents a comprehensive investigation of the mechanical behavior of SP-RSRC under various strain rates,employing a combination of experimental,theoretical,and numerical analyses.Firstly,quasi-static and dynamic compression tests were performed on SP-RSRC utilizing a universal testing machine and split Hopkinson pressure bar(SHPB)apparatus.Nonlinear stress-strain relationships of SP-RSRC were obtained for strain rates ranging from 1×10^(−3) to 3065 s^(−1).The results indicated that the composite showed evident strain rate sensitivity,along with nonlinearity.Then,a nonlinear visco-hyperelastic constitutive model was developed,consisting of a hyperelastic component utilizing the 3rd-order Ogden energy function and a viscous component employing a rate-dependent relaxation time scheme.The model accurately characterized the dynamic mechanical response of SP-RSRC,effectively mitigating the challenge of calibrating an excessive number of material parameters inherent in conventional viscoelastic models.Furthermore,the simplified rubber material(SRM)model,integrated within the LS-DYNA software,was chosen to depict the mechanical properties of SP-RSRC in numerical simulations.The parameters of the SRM model were further calibrated based on the strain-stress relationships of SP-RSRC,as predicted by the developed nonlinear visco-hyperelastic constitutive model.Finally,an inverse ballistic experiment using a single-stage air gun was conducted for SP-RSRC.Numerical simulations of SHPB experiments and the inverse ballistic experiment were then performed,and the reliability of the calibrated SRM model was verified by comparing the results of experiments and numerical simulations.This study offers a valuable reference for the utilization of SP-RSRC in the realm of impact protection.