固定化酶催化合成CCK-8C-端三肽衍生物

报道胆囊收缩素（CCK-8）C-末端片段三肽衍生物外Hpac-Met_Asp(Cam为起始 原料，采用三种固定化酶--α-糜蛋白酶／Celite-545、木瓜蛋白酶／VA-Epoxy、 步酶促反应得到目标三肽化合物．对酶的专一性、酶的固定化、溶剂选择和合成条 件等进行了研究，比较了自由酶法与固定化酶法的结果．     

含糖聚合物的酶促合成

介绍含糖聚合物的酶促催化合成研究进展，主要包括主链含糖聚糖酯，支链含糖聚合物，中心为糖的星形取合物，硅烷主链含糖聚合物等。主链含糖聚合物直接由酶促催化酯化或酯交换作用制得；支链含糖聚合物由酶促合成糖酯单体及单体的化学聚合两步制得。     

β-双取代和β，β＇-取代可溶性导电聚噻吩的合成与表征

自上世纪90年代，Burroughes等人首次报道导电聚合物材料PPV（poly-p-phenylene vinylene）的发光性能后，聚合物发光研究获得了迅猛的发展。聚噻吩类聚合物因具有良好的稳定性和较高的发光活性而受到了人们广泛的关注。由于取代基的不同，聚噻吩类衍生物的发光颜色和发光强度均不相同，因此合成新型材料始终是这一领域的热点和基础工作。Yoshino等人以无水FeCl3为催化剂合成可溶性取代聚噻吩的方法，因条件温和，反应易控制，产率较高而被学术界广泛采用。我们参考并改进该方法成功地合成了β-取代聚噻吩的基础上，进一步合成了β，β’-双取代聚噻吩，以期在改变聚合物链性能的同时，调控并改善聚合物光、电性能。本文介绍了其中四种材料的合成方法、表征结果及光学性能的初步研究结果。     

含糖聚合物的合成

综述了含糖聚合物合成的研究发展，介绍了化学和酶催化合成不饱合含糖单体的方法，以及含糖聚合物通过自由基、阳离子、阴离子聚合和高分子改性等四种方法制备途径，同时也探讨了这些含糖聚合物在医药、生物材料、水凝胶等领域中的应用。     

光致变色聚合物研究进展

本文主要介绍了9类光致变色聚合物的研究状况，包括光致变色螺吡喃聚合物、螺噁嗪聚合物、二芳基乙烯光致变色聚合物、偶氮苯类光致变色聚合物、苯氧基萘并萘醌光致变色聚合物、俘精酰亚胺光致变色共聚物、硫靛光致变色共聚物、双硫腙光致变色聚合物以及二氢吲嗪光致变色聚合物等。讨论了聚合物的合成、光致变色性质、影响聚合物性质的因素，并对光致变色聚合物未来的研究重点和方向作了展望。     

酶法合成头孢丙烯工艺研究

采用酶催化法,以7-氨基-3-[(Z)-烯丙-1-基]-3-头孢环-4-羧酸(7-APCA)为母核,D-对羟苯甘氨酸甲酯(D-HPGME)为酰基供体,水作溶剂,在固定化青霉素G酰化酶的催化作用下合成头孢丙烯。本研究中催化酶的载体采用氨基和环氧载体,筛选合适的酶活,考察反应pH、温度、投酶量、投料比、底物浓度等多个因素对酶法合成头孢丙烯的影响。通过对酶法合成头孢丙烯的工艺条件的优化,为头孢丙烯绿色生产技术的推行打下基础。     

大豆种皮过氧化物酶代替辣根过氧化物酶测定血糖

分别采用辣根过氧化物酶法、大豆种皮过氧化物酶法及血糖仪法测定了6只小鼠在空腹和进食后2 h的血糖值。对3种方法的测定值经统计分析,上述3种方法测得的血糖值无显著差异。因此采用大豆种皮过氧化物酶代替辣根过氧化物酶测定小鼠血糖是可行的。     

光致变色聚合物研究进展

本文主要介绍了9类光致变色聚合物的研究状况,包括光致变色螺吡喃聚合物、螺噁嗪聚合物、二芳基乙烯光致变色聚合物、偶氮苯类光致变色聚合物、苯氧基萘并萘醌光致变色聚合物、俘精酰亚胺光致变色共聚物、硫靛光致变色共聚物、双硫腙光致变色聚合物以及二氢吲嗪光致变色聚合物等.讨论了聚合物的合成、光致变色性质、影响聚合物性质的因素,并对光致变色聚合物未来的研究重点和方向作了展望.     

包合铁卟啉的环糊精聚合物作为过氧化物朊酶模型物的研究

将β-环糊精交联聚合物（β-CDP）包合铁卟啉（FeTPPS4）形成的固相超分子作为过氧化物朊酶的模拟物，考察影响超分子包合物形成的各种因素，研究了固相超分子催化苯酚一过氧化氢的反应机理，测定了固相超分子的稳定常数，探讨了各种底物对固相超分子酶的模拟物的影响．实现了过氧化氢对4-氨基安替比林一对氯苯酚的催化显色反应，并应用于过氧化氢的酶法分析．     

光致变色聚合物研究进展

本文主要介绍了9类光致变色聚合物的研究状况,包括光致变色螺吡喃聚合物、螺嗪聚合物、二芳基乙烯光致变色聚合物、偶氮苯类光致变色聚合物、苯氧基萘并萘醌光致变色聚合物、俘精酰亚胺光致变色共聚物、硫靛光致变色共聚物、双硫腙光致变色聚合物以及二氢吲嗪光致变色聚合物等。讨论了聚合物的合成、光致变色性质、影响聚合物性质的因素,并对光致变色聚合物未来的研究重点和方向作了展望。     

Peroxidase-catalyzed in situ polymerization of surface orientated caffeic acid

Nanoscale surface patterning and polymerization of caffeic acid on 4-aminothiophenol-functionalized gold surfaces has been demonstrated with dip pen nanolithography (DPN). The diphenolic moiety of caffeic acid can be polymerized by biocatalysis with laccase or horseradish peroxidase. In the present study, the DPN patterned features were polymerized in situ through the use of the peroxidase. Using samples prepared by DPN, microcontact printing, and adsorption on macroscopic substrates, the products were characterized by electrostatic force microscopy (EFM), MALDI-TOF, X-ray photoelectron spectroscopy (XPS), UV-vis, and FT-IR. The in situ surface polymerization resulted in the formation of a quinone structure, while the phenyl ester formed in bulk polymerization reactions was not detected. A different coupling site was observed when comparing the polymers obtained from solution (bulk) vs the surface DPN reactions. The structural differences were attributed to surface-induced pre-organization and orientation of the monomers prior to the enzymatic polymerization step. The results of this study expand the application of DPN technology to surface modification and surface chemistry reactions wherein stereo-regularity and regioselectivity can be exploited.     

Hydrazide-functionalized hollow porous poly(2-hydroxyethyl methacrylate-co-ethylene dimethacrylate) spheres for immobilization of enzyme

Hollow porous poly(2-hydroxyethyl methacrylate-co-ethylene dimethacrylate)(HEMA-co-EDMA) spheres were prepared by emulsifier-free emulsion polymerization, swelling, seed emulsion polymerization and extraction. Then the spheres activated with 2,4,6-trichloro-1,3,5-triazine were functioned with adipohydrazide (AH). After periodate oxidation of its carbohydrate moieties, horseradish peroxidase was immobilized on the hydrazide-functionalized hollow porous poly(HEMA-co-EDMA) spheres. The amount of immobilized enzyme was up to 43.4 μg of enzyme/g of support. Moreover, the immobilized horseradish peroxidase exhibited high activity and good stability.     

Enzymatic polymerization of vinyl monomers

The possibility of using horse radish peroxidase as a catalyst for polymerization of monomers (vinylformamide and sodium vinylsulfonate) in the presence of hydrogen peroxide and 2,4-pentanedione in aqueous medium at room temperature was studied.     

Horseradish peroxidase‐based hybrid nanoflowers with enhanced catalytical activities for polymerization reactions of phenol derivatives

Catalytic activity and stability of HRP‐Cu²⁺ hybrid nanoflowers (hCu‐NFs) in the polymerization reactions of phenol derivatives was investigated. It was observed that the catalytic activity and stability of hybrid nanoflowers on the polymerization of the phenol derivatives was considerably higher compared to free Horseradish peroxidase (HRP) enzyme. The hCu‐NFs effectively polymerized phenolic compounds as a novel nanobiocatalyst and led to polymers having quite high yields, molecular weights, and thermal stabilities compared to free HRP enzyme. The hCu‐NFs provide substantial repeated use and showed some degree of catalytic activity even after fourth cycle experiment in the polymerization reactions.     

PEROXIDASE,HEMATIN, AND PEGYLATED-HEMATIN CATALYZED VINYL POLYMERIZATIONS IN WATER

Horseradish peroxidase-, hematin- and pegylated-hematin mediated polymerization of sodium styrene sulfonate and sodium acrylate in water is reported. Molecular weight and yields were influenced by the concentrations of hydrogen peroxide and initiator, 2,4-pentanedione. Hematin and pegylated-hematin were studied in lieu of peroxidase at pH 11.0 and 7.0 in aqueous solution, respectively. Polymer with a high molecular weight (Mn = 223,520) was formed when the pegylated-hematin was used as the catalyst. The results demonstrate vinyl polymerizations in an all aqueous process in high yield and molecular weight catalyzed by peroxidase as well as biomimetic catalysts.     

Biocatalytic synthesis of polypyrrole powder, colloids, and films using horseradish peroxidase

Polypyrrole was synthesized in high yield by a biocatalytic method in mild aqueous media using hydrogen peroxide as oxidizer. A redox mediator, 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) diammonium salt, was used to oxidize the pyrrole. ABTS is a very effective peroxidase substrate, which was enzymatically oxidized to generate a radical cation that in turn was able to chemically oxidize pyrrole. This indirect biocatalytic method was implemented because pyrrole is not a substrate of horseradish peroxidase, however, the polymerization process was successfully optimized and later adapted to prepare also polypyrrole thin films and water dispersible polypyrrole colloids. The polypyrrole powder and colloids were characterized by scanning electron microscopy, X-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy, electrical conductivity, and thermogravimetric analysis. In addition, the deposition of the polypyrrole thin film was monitored using a quartz-crystal microbalance and its morphology studied by optical and scanning electron microscopy. The biocatalytic polymerization of pyrrole results in a polymer spectroscopically very similar to chemically synthesized polypyrrole.     

Peroxidase-based oxidative polymerization of monolignols

Oxidative polymerization of the monolignols (sinapyl alcohol [SA] and coniferyl alcohol [CA]) has been performed using enzyme-based biocatalysts. The oxidation of SA, CA, or an SA/CA mixture has been carried out using peroxidase enzyme–assisted H₂O₂/t-BHP (oxidation reagent). The reaction provided radicals with high reactivity, in turn yielding a variety of polymeric structures. The efficiency of the oxidative polymerization system has been evaluated in terms of substrate conversion. Also, the polymeric products were characterized with the gel permeation chromatography technique (GPC). Accordingly, optimum experimental parameters have been set up (e.g. temperature, type of peroxidase enzyme, and oxidation reagent). Under optimum conditions, a maximum of 90% of the SA was transformed to polymeric products with MW = 3188 Da, Mn = 1115 Da, and PD = 2.8.     

辣根过氧化物酶酶促体系引发丙烯酰胺聚合的研究

对辣根过氧化物酶(HRP)、H2O2和乙酰丙酮(ACAC)组成的三元醇促体系引发的丙烯酰胺(AAM)聚合进行了研究。在膨胀计中考察了反应温度和HRP、ACAC、H2O2及AAM初始浓度对酶促体系引发AAM聚合动力学行为的影响,确定了适宜的反应条件。用FTIR和GPC对聚合产物进行表征,得到的聚丙烯酰胺的数均分子量为10^5-10^6,分子量分布指教DI为2-3。     

Immobilized horseradish peroxidase as a reusable catalyst for emulsion polymerization

The study on the adsorption of horseradish peroxidase (HRP) onto silicon wafers was carried out by means of in situ ellipsometry, atomic force microscopy (AFM) and contact angle measurements. A smooth HRP layer adsorbed onto Si wafers. The enzymatic activity of free or adsorbed HRP was determined by the oxidation of 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) and by the emulsion polymerization of ethylene glycol dimethacrylate (EGDMA). Upon adsorbing, HRP molecules might have undergone some conformational changes, which caused a small reduction of enzymatic activity in comparison to that observed for HRP solution. However, it was possible to reuse the same HRP-covered Si wafer as catalyst in the polymerization of EGDMA three times.     

过氧化物酶催化酚聚合的研究

研究过氧化物酶在非水介质中催化酚类化合物的聚合。探讨了有机溶剂的浓度，溶剂极性，体系ＰＨ值、酶浓度等因素对聚酚分子量的影响；分析了聚酚的链结构。结果表明，酚分子之间通过酚羟基的邻位或对位相互连结。形成了分子链上带有酚羟基的聚酚树脂；通过调节聚合参数，可以改变聚酚的分子量。