Pazol Jessika, Vázquez Adriana, Nicolau Eduardo
Department of Chemistry, University of Puerto Rico, Rio Piedras Campus, 17 Ave. Universidad Ste. 1701, San Juan, Puerto Rico, 00925-2537, USA; Molecular Sciences Research Center, University of Puerto Rico, 1390 Ponce De Leon Ave, Suite 2, San Juan, Puerto Rico, 00931-3346, USA.
Department of Chemistry, University of Puerto Rico, Rio Piedras Campus, 17 Ave. Universidad Ste. 1701, San Juan, Puerto Rico, 00925-2537, USA.
Colloids Surf B Biointerfaces. 2019 Nov 1;183:110418. doi: 10.1016/j.colsurfb.2019.110418. Epub 2019 Aug 6.
The design of interfaces that selectively react with molecules to transform them into compounds of industrial interest is an emerging area of research. An example of such reactions is the hydrolytic conversion of ester-based molecules to lipids and alcohols, which is of interest to the food, and pharmaceutical industries. In this study, a functional bio-interfaced layer was designed to hydrolyze 4-nitrophenyl acetate (pNPA) and Ricinus Communis (castor) oil rich in triglycerides using lipase b from Candida antarctica (CALB, EC 3.1.1.3). The attachment of CALB was performed via non-covalent immobilization over a polymer film of vertically aligned cylinders that resulted from the self-assembly of the di-block copolymer polystyrene-block-poly(4-vinyl pyridine) (PS-b-P4VP). This polymer-lipase model will serve as the groundwork for the design of further bioactive layers for separation applications requiring similar hydrolytic processes. Results from the fabricated functional bio-interfaced material include cylinders with featured pore size of 19 nm, d spacing of 34 nm, and ca. 40 nm of thickness. The polymer-enzyme layers were physically characterized using AFM, XPS, and FTIR. The immobilized enzyme was able to retain 91% of the initial enzymatic activity when using 4-nitrophenyl acetate (pNPA) and 78% when exposed to triglycerides from castor oil.
设计能够与分子选择性反应以将其转化为具有工业价值化合物的界面是一个新兴的研究领域。此类反应的一个例子是酯基分子水解转化为脂质和醇类，这对食品和制药行业具有重要意义。在本研究中，设计了一种功能性生物界面层，使用来自南极假丝酵母的脂肪酶b（CALB，EC 3.1.1.3）水解乙酸对硝基苯酯（pNPA）和富含甘油三酯的蓖麻油。CALB通过非共价固定附着在由二嵌段共聚物聚苯乙烯-嵌段-聚（4-乙烯基吡啶）（PS-b-P4VP）自组装形成的垂直排列圆柱状聚合物薄膜上。这种聚合物-脂肪酶模型将为设计用于需要类似水解过程的分离应用的进一步生物活性层奠定基础。所制备的功能性生物界面材料的结果包括具有19nm特征孔径、34nm d间距和约40nm厚度的圆柱。使用原子力显微镜（AFM）、X射线光电子能谱（XPS）和傅里叶变换红外光谱（FTIR）对聚合物-酶层进行了物理表征。当使用乙酸对硝基苯酯（pNPA）时，固定化酶能够保留91%的初始酶活性，当暴露于蓖麻油中的甘油三酯时，保留率为78%。
