Alkaline System?Electrochemical Glucose Sensor

Electrolyte: ?NaOH or KOH, 0.1M, 50mL

Glucose Solution: 1, 10, 100, 1000mM

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1.?Contrast the reaction with or without glucose substrate

CV

Scan Rate: ?50mV/s

Window Potential: adjustable

Glucose Solution: with or without 1mM

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2.?Compare whether the electrode surface conforms to the diffusion law under different scanning rates

CV

Scan Rate: ?4, 9, 16, 25, 36,49, 64, 81, 100mV/s

Window Potential: adjustable

Glucose Solution: 2mM

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3.?Compare the reaction of different glucose concentration at the same scanning rate on the electrode surface

CV

Scan Rate: ?50mV/s

Window Potential: adjustable

Glucose Solution: 0, 5, 10, 50, 100, 200, 400, 600, 800, 1000μM?(adjustable)

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4.?Determination of optimal reaction potential

IT

Time: ? 500s

Potential Setting: 0.4, 0.45, 0.5, 0.55, 0.6V (adjustable)

e.g.

1. Use IT to flatten the curve, and then wait for 200s. In the 200s, the concentration of glucose solution in the electrolyte will increase by 1mM every 50s. (Drop 50μL glucose solution, which can be ignored for 50 mL electrolyte system)

2. The optimal reaction potential should be comprehensively considered in terms of LOD (current noise), linear range and sensitivity (response current).

5.?Determination of glucose sensor sensitivity

IT

Time: ? 2500s

Potential Setting: use the results of step 4

e.g.

1. Use IT to flatten the curve, and then wait for 200s. In the 200s, the concentration of glucose solution in the electrolyte will increase by?1μM?every 50s (0-10μM);?10μM?every 50s (0-10μM);?100μM?every 50s (0-10μM); 1000μM?every 50s (0-10μM).

2. Fitting points on step current is sensitivity.

3. S/N=3, LOD=3*σ/s?(σ≈0.03, s=sensitivity).

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6.?Test the selectivity of glucose sensor to glucose

IT

Time: ? 1000s

Potential Setting: use the results of step 4

e.g.

1. Use IT to flatten the curve, and then wait for 200s. In the 200s, Drop Glucose,?Lactose,?Sucrose,?Fructose,?Urea, Nacl, Kcl,?Ascorbic Acid,?Uric Acid,?Dopamine and?Glucose, respectively, into the electrolyte system.

2. This step is to determine whether the interfering substance will affect the sensor. Other types of interfering substances can be replaced according to different applications.

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7.?Test the stability of glucose sensor

IT

Time: ? 1000s

Potential Setting: use the results of step 4

Glucose Solution: 0.2mM (adjustable)

e.g.

1. At the best test potential, record the current density on the first day, and then record it every 3?days, 8 times in total.

2. Take the response current of the first day as the reference, and use all the data as the percentage point graph.

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8.?Real engineering sample test

IT

Time: ? 300s

Potential Setting: use the results of step 4

e.g.

1. Use IT to flatten the curve, and then wait for 200s. In the 200s, Drip real engineering samples, such as blood, sugary drinks, etc. Then, observe the response potential and bring it into the sensitivity formula. Compare the glucose concentration based on sensitivity with the real glucose concentration.

2. If you need human or experimental animal samples, please pass the approval of the Scientific Ethics Committee.