In the field of biosensing analysis, especially in the development of implantable glucose sensors and dual analyte sensors, glucose dehydrogenase (GDH) is the core functional raw material that determines detection accuracy and stability. However, glucose dehydrogenase (GDH) cannot be directly used for sensor preparation and requires specialized process modification to adapt to electrochemical detection scenarios and achieve efficient and stable glucose signal conversion.

Glucose dehydrogenase

Glucose dehydrogenase (GDH): Sensor applications require exclusive process adaptation

Glucose dehydrogenase (GDH) itself has excellent glucose specific catalytic performance, can catalyze glucose dehydrogenation reaction and complete electron transfer, and is the core carrier for converting glucose concentration into electrical signals. However, the molecular structure of glucose dehydrogenase (GDH) in its original state is compact, and the active sites are difficult to fully expose, and cannot be directly fixed on the electrode surface, which cannot meet the long-term use requirements of the sensor. Therefore, targeted process modification of glucose dehydrogenase (GDH) is the core prerequisite for its adaptation to sensors and a key step in improving the overall performance of sensors.

Three step core modification process of glucose dehydrogenase (GDH)

1. Enzyme molecule unfolding: Activate GDH active site

The first step is to perform molecular unfolding treatment on glucose dehydrogenase (GDH), which is the basis for activating enzyme activity. Place glucose dehydrogenase (GDH) in a PBS buffer solution with a concentration of 3mol/L (range 1-6 mol/L) urea and incubate at 4 ° C for 12 hours (duration 8-24 hours). Mild treatment conditions will not damage the core structure of GDH, but can fully stretch the compact GDH molecules, thoroughly expose the internal active sites, greatly improve the subsequent binding efficiency with glucose molecules, and enhance the catalytic reaction rate from the source.

2. Electronic mediator modification: enhances electron transfer efficiency

After molecular unfolding, electron mediator modification is performed on glucose dehydrogenase (GDH) to address the pain point of slow electron transfer. Mix the unfolded glucose dehydrogenase (GDH) with 5mg/mL (range 1-10mg/mL) ruthenium/osmium complex, add carbodiimide and N-hydroxysuccinimide as coupling agents, react at 4 ℃ for 12 hours, and purify by ultrafiltration dialysis, allowing the electron mediator to covalently bind with glucose dehydrogenase (GDH). This step can open up the electron transfer channel from the enzyme to the electrode, achieving fast and efficient electron transfer. If further performance improvement is needed, secondary modification and purification can be carried out to optimize the overall conductivity of GDH.

3. Cross linked fixation: ensuring the stability of the sensing membrane

The final step is cross-linking fixation, allowing glucose dehydrogenase (GDH) to stably adhere to the electrode. Mix the modified glucose dehydrogenase (GDH) with glutaraldehyde at a concentration of 1% (range 0.1-5%) for 60 minutes (duration 30-180 minutes), and then uniformly coat it on the surface of the sensor electrode by immersion coating to form a dense and stable glucose sensing membrane. Through cross-linking fixation, it can effectively prevent the loss of glucose dehydrogenase (GDH) molecules during implantation or use, ensuring the stability and detection consistency of the sensor for long-term use, and adapting to various harsh scenarios such as implantation.

New Desheng GDH products: Adapting processes to assist sensor research and development

Xindesheng can provide high-quality glucose dehydrogenase (GDH) raw materials. With stable supply capacity and strict quality inspection system, Xindesheng's GDH products have strong batch consistency, which can effectively solve the pain points of high imported raw material prices and slow supply. It is a high-quality choice for enterprise research and development production. If you need enzyme preparation materials suitable for sensor technology, please feel free to consult Hubei Xindesheng for exclusive products and technical solutions.