1. Tailored diffusion limiting membrane for microneedle glucose sensors with wide linear range.
- Author
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Wu, Minfang, Li, Liang, Yu, Rongying, Zhang, Zebo, Zhu, Boyu, Lin, Junshu, Zhou, Lin, and Su, Bin
- Subjects
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GLUCOSE , *CONTINUOUS glucose monitoring , *BLOOD sugar monitors , *GLUCOSE oxidase , *BLOOD sugar monitoring , *BLOOD sugar , *EXTRACELLULAR fluid - Abstract
Continuous glucose monitoring is very important to daily blood glucose control in diabetic patients, but its accuracy is limited by the narrow linear range of the response of biosensor to the glucose concentration because of the oxygen starvation in tissue and the limited maximum conversion rate of glucose oxidase. In this work, a biocompatible diffusion limiting membrane based on two medical-grade polyurethanes is developed via blending modification to restrict the diffusion flux of glucose to match the oxygen concentration and the maximum conversion rate. The expansiveness of the linear range for the nanomaterials-modified electrode in the glucose biosensor can be achieved through the regulation of two polyurethanes, the solvent, and the thickness of the membrane. In addition, the mass transport of hydrogen peroxide and interfering substances is also limited of the membrane. The in vitro experiments demonstrated that the membrane-modified microneedle biosensor exhibited a rapid response to the concentration variation of glucose, a wide linear range that is sufficient to cover the blood concentration of healthy and diabetic people, the ability to resist the oxygen concentration fluctuation and interfering substances, good reproducibility and long-term stability. The custom wearable electrochemical system, possessing these characteristics, has been proven to accurately monitor the blood concentration in a living rat in real time. This demonstrates a significant potential for application in both daily and clinical blood glucose monitoring. [Display omitted] • A biocompatible membrane, derived from two polyurethanes and formulated through predissolution in a binary solvent, modified via physical blending, formed through ultrasonic spraying, proficiently regulates the diffusion of glucose to the biosensor. • The linear range can be expanded by the regulation of the hydrophilic and hydrophobic polyurethanes ratio, the solvents and the membrane thickness. • The membrane-decorated biosensor exhibited a broad linear response range, resistance to fluctuations in oxygen concentration and interference, low relative standard deviation, excellent reproducibility and long-term stability. • In vivo experiment confirms the CGM device combined with the membrane-coated glucose biosensor can monitor interstitial fluid glucose concentration in real-time accurately for 8 days. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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