Yun et al. [5] developed another new method to construct micro-biosensors based on CNTs. A bundle www.selleckchem.com/products/Tipifarnib(R115777).html of nanotubes was welded onto the tip of a tungsten needle under a microscope, the resulting needle was encased in glass and a polymer coating leaving only the tip of the needle exposed. The glucose oxidase was physically attached on the needle tip. This biosensor detected glucose and PS-341 the amperometric response showed a high sensitivity with a low detection limit.Because Multiwall Carbon Nanotubes (MWCNTs) are cheaper and easier to be treated by acid than single-wall CNTs (SWCNTs) without losing their excellent electroconductivity, in this paper they were used as the electrode material to fabricate a micro needle-type glucose biosensor.
What we really interested in is whether such Inhibitors,Modulators,Libraries a kind of biosensor Inhibitors,Modulators,Libraries could be used in an online glucose monitoring system and how its long-time stability would be. After optimization of various technical parameters, it is found that this Inhibitors,Modulators,Libraries new needle-type glucose biosensor is useful for continuous glucose monitoring and has good potential applications in the field of real-time monitoring.2.?Results and Discussion2.1. Influence of percentage of GOX to the current response in the needle-type biosensorIn our previous work (data not shown), current responses to hydrogen peroxide of the needle electrodes fabricated with different conducting Inhibitors,Modulators,Libraries materials, such as a pure graphite powder sealed electrode, a mixture of MWCNTs and graphite powder sealed electrode, a pure MWCNTs sealed electrode, were studied.
It was found that the needle-type electrode showed the highest response to H2O2 when the ratio of graphite and carbon nanotubes up to 1:2 (w/w). This Inhibitors,Modulators,Libraries optimized mixture Inhibitors,Modulators,Libraries of MWCNTs/graphite powder, together with different Inhibitors,Modulators,Libraries percentages of Gox powder, were packed Inhibitors,Modulators,Libraries into the glass capillary to construct the glucose needle-type biosensors. The current responses of this biosensor to the presence of different glucose concentrations were then studied (see Figure 1). As indicated from this figure, the current response of biosensor increased with the percentage of Gox. At certain range of Gox, a larger amount of Gox in the biosensor correspond to a higher current response.
When the composition ratio of MWCNTs mixture/Gox is increased from 5:3 to 5:5, the Anacetrapib intensity of current response was not increased so obviously.
This indicates that when the percentage of Gox is increased to a certain level, the corresponding increase of current response to the percentage of Gox become small. The reason Brefeldin_A is that the decrease of percentage of MWCNTs results in an increase of the amount of Gox in the whole electrical material, therefore the electrical conductivity and hydrogen peroxide catalysis of the biosensor will be decreased. This decrease selleck catalog Dovitinib buy can counteract the effect of Gox in the biosensor, thus the biosensor can’t display a sustained increase in current response along with the increase of Gox amount.