Reinicke Stefan, Fischer Thilo, Bramski Julia, Pietruszka Jörg, Böker Alexander
Fraunhofer Institute for Applied Polymer Research (IAP) Geiselbergstraße 69 Potsdam-Golm 14476 Germany
Chair of Polymer Materials and Polymer Technologies, University of Potsdam Potsdam-Golm 14476 Germany.
RSC Adv. 2019 Sep 9;9(49):28377-28386. doi: 10.1039/c9ra04000e.
We present a novel protocol for the synthesis of enzymatically active microgels. The protocol is based on the precipitation polymerization of -isopropylacrylamide (NIPAm) in the presence of an enzyme and a protein binding comonomer. A basic investigation on the influence of different reaction parameters such as monomer concentration and reaction temperature on the microgel size and size distribution is performed and immobilization yields are determined. Microgels exhibiting hydrodynamic diameters between 100 nm and 1 μm and narrow size distribution could be synthesized while about 31-44% of the enzyme present in the initial reaction mixture can be immobilized. Successful immobilization including a verification of enzymatic activity of the microgels is achieved for glucose oxidase (GOx) and 2-deoxy-d-ribose-5-phosphate aldolase (DERA). The thermoresponsive properties of the microgels are assessed and discussed in the light of activity evolution with temperature. The positive correlation of enzymatic activity with temperature for the GOx containing microgel originates from a direct interaction of the enzyme with the PNIPAm based polymer matrix whose magnitude is highly influenced by temperature.
我们提出了一种合成具有酶活性微凝胶的新方案。该方案基于在酶和蛋白质结合共聚单体存在下，N-异丙基丙烯酰胺（NIPAm）的沉淀聚合反应。我们对不同反应参数（如单体浓度和反应温度）对微凝胶尺寸和尺寸分布的影响进行了基础研究，并测定了固定化产率。可以合成流体动力学直径在100nm至1μm之间且尺寸分布窄的微凝胶，同时初始反应混合物中约31-44%的酶能够被固定化。对于葡萄糖氧化酶（GOx）和2-脱氧-D-核糖-5-磷酸醛缩酶（DERA），实现了成功的固定化，包括对微凝胶酶活性的验证。根据微凝胶活性随温度的变化情况，对其热响应特性进行了评估和讨论。含GOx微凝胶的酶活性与温度呈正相关，这源于酶与基于PNIPAm的聚合物基质的直接相互作用，其相互作用强度受温度的影响很大。
