Differential Pulse Voltammetry

Stages

1. 1.
   Electrode functionalisation and assay assembly(library_build)

   This stage creates the functional biosensor surface needed for analyte detection.

   Selection: Functionalise 3D graphene foam electrodes with Pyr-NHS, bind Aβ42 and Aβ40 antibodies, and block with BSA to create the assay surface.

2. 2.
   Electrochemical performance measurement(functional_characterization)

   This stage quantifies whether the assembled biosensor performs adequately for Aβ42 and Aβ40 detection.

   Selection: Use DPV to measure stability and analyte detection performance.

3. 3.
   Interference assessment(counter_screen)

   This stage checks whether the biosensor signal is affected by a related non-target biomarker.

4. 4.
   Spiked plasma validation(confirmatory_validation)

   This stage tests whether the biosensor retains utility in a more realistic biological sample matrix than buffer-only measurements.

   Selection: Validate assay performance in spiked-diluted human plasma.

Steps

1. 1.
   Functionalise 3D graphene foam electrodes with Pyr-NHSelectrode substrate and surface linker

   Enable effective and stable antibody immobilisation on the electrode surface.

   Surface functionalisation is performed first because it prepares the graphene foam for subsequent antibody binding.

2. 2.
   Bind Aβ42 and Aβ40 antibodies to the functionalised electrodecapture interface assembly

   Create analyte-specific recognition surfaces for Aβ42 and Aβ40 detection.

   Antibody binding follows Pyr-NHS functionalisation because the linker chemistry is used to enable antibody immobilisation.

3. 3.
   Block the electrode surface with BSAblocking reagent

   Minimise non-specific binding on the electrode surface.

   Blocking is performed after antibody immobilisation to reduce non-specific interactions before measurement.

4. 4.
   Measure biosensor performance by DPVbiosensor under test and readout method

   Assess stability and detection performance for Aβ42 and Aβ40.

   Electrochemical measurement is performed after assay assembly because the completed biosensor must be read out to determine performance.

5. 5.
   Test interference from tau217 proteinbiosensor under specificity challenge

   Evaluate whether a non-target AD-related protein interferes with Aβ detection.

   Interference testing follows primary performance measurement to check specificity after sensitive detection has been established.

6. 6.
   Validate the biosensor in spiked-diluted human plasmabiosensor under matrix validation

   Confirm assay function in a human plasma matrix.

   Plasma validation is performed after analytical characterization to test whether the assay remains usable in a more realistic sample matrix.