Taylor M A, Jones M N, Vadgama P M, Higson S P
School of Biological Sciences, University of Manchester, UK.
Biosens Bioelectron. 1995;10(3-4):251-60. doi: 10.1016/0956-5663(95)96844-o.
Many biosensors have been described for the measurement of glucose in order to monitor diabetic patients. Glucose oxidase has been used commonly in the construction of glucose sensors but the performance of this enzyme is limited by enzyme saturation kinetics, which restrict the measurement of clinically relevant glucose concentrations (0 to 25 mM). Diffusion limiting membranes have been described that result in the exposure of the enzyme to lower concentrations of glucose than are present in the bulk test solution. Recently a liposomal enzyme electrode was reported whereby glucose oxidase was encapsulated within liposomes so that the lipid bilayer was the diffusion limiting membrane. It was shown that the electrode response was defined by the lipid constituents of the liposome, and that a linear response to glucose could be achieved up to 40 mM. This paper describes research undertaken to improve the methods of production of a liposomal enzyme electrode. Improved immobilization of liposomes is demonstrated with the use of poly-L-lysine solution. The variation in electrode response with respect to the amount of glucose oxidase liposomally encapsulated is reported. The new method allows a greater number of sensors to be produced from a single batch of liposomes. Studies also show the biofouling effects of the lipid constituents of ruptured liposomes on the response of the electrode to glucose over time.
为了监测糖尿病患者，人们已经描述了许多用于测量葡萄糖的生物传感器。葡萄糖氧化酶在葡萄糖传感器的构建中被广泛使用，但其性能受到酶饱和动力学的限制，这限制了对临床相关葡萄糖浓度（0至25 mM）的测量。人们已经描述了扩散限制膜，其结果是使酶暴露于比大量测试溶液中更低的葡萄糖浓度。最近报道了一种脂质体酶电极，其中葡萄糖氧化酶被包裹在脂质体内，因此脂质双层成为扩散限制膜。结果表明，电极响应由脂质体的脂质成分决定，并且对葡萄糖的线性响应可以达到40 mM。本文描述了为改进脂质体酶电极生产方法而进行的研究。使用聚-L-赖氨酸溶液证明了脂质体固定化的改进。报道了电极响应随脂质体包裹的葡萄糖氧化酶量的变化。新方法允许从一批脂质体中生产更多数量的传感器。研究还表明，破裂脂质体的脂质成分随时间对电极对葡萄糖的响应具有生物污染作用。
