Lab Practicals for Biomedical Engineers

by | Sep 1, 2025 | Uncategorized

On this page we discuss Biosensor Lab Practicals for Biomedical Engineers.

Glucose biosensor practical
Potassium biosensor practical

Teaching Biomedical Engineering with Biosensors: A Hands-On Guide to Glucose & Potassium Sensing

Biomedical engineering sits at the fascinating crossroads of biology, chemistry, and technology. For students, there’s no better way to understand this interdisciplinary field than by getting hands-on with the devices at the heart of modern healthcare: biosensors.

In this blog, we’ll explore how to use practical biosensor labs to teach core concepts, focusing on two key examples: a glucose sensor (using amperometry) and a potassium sensor (using open-circuit potentiometry). We’ll be using the SenseItAll (SIA) teaching platform from ZP Technologies to demonstrate just how straightforward and effective these labs can be.

Why Should Biomedical Students Care About Biosensors?

Biosensors, especially wearable ones, are more than just gadgets; they are perfect teaching tools because they bring together every discipline a biomedical engineer studies:

  • Biology: The biological system being measured, whether it’s blood or interstitial fluid.

  • Chemistry: The chemical reactions, such as the conversion of glucose into glucolactone and hydrogen peroxide.

  • Biochemistry: Enzyme kinetics, described by models like Michaelis-Menten.

  • Electrochemistry: The sensing modalities, like amperometry and potentiometry, used to detect analytes.

  • Material Science: The polymers, printed electrodes, and functionalized surfaces that make sensors work.

  • Electromechanical Engineering: The design of devices, especially wearables, that attach to the body for continuous monitoring.

  • Data Science: Biosensors are conduits for data. The signals they generate are the foundation for real-world AI and health analytics.

By working with biosensors, students aren’t just learning theory—they are building the data pipelines for the future of digital health.

Lab 1: The Glucose Sensor (Amperometry)

The Principle:
The glucose sensor is a classic example of an electrochemical biosensor. It uses an enzyme, glucose oxidase, which is pre-immobilized on the sensor. The reaction is as follows:

  1. Glucose reacts with the enzyme to form glucolactone.

  2. In the process, oxygen (a co-factor) is converted into hydrogen peroxide (H₂O₂).

  3. The H₂O₂ diffuses to the surface of the electrode.

  4. A specific potential (~650 mV) is applied, oxidizing the H₂O₂ and generating a measurable electrical current.

  5. This current is directly proportional to the glucose concentration.

This very principle is used in commercial devices for diabetes management worldwide.

The Teaching Demo:
Using the SenseItAll (SIA) system, setting up the experiment is simple:

  1. Scan the amperometry QR code with the app. This tells the connected meter exactly what to do.

  2. Place a sensor strip and add a buffer solution (zero analyte) to establish a baseline.

  3. Initiate the measurement via the app. You’ll see an initial charging current that quickly settles into a stable baseline.

  4. Add a shot of glucose analyte. The current instantly spikes and then settles at a new, higher baseline, representing the new concentration.

  5. The data is automatically uploaded to the cloud for immediate analysis.

Students can repeat this with increasing concentrations (e.g., 0 mM, 5 mM, 10 mM, 15 mM, 20 mM) to build a calibration curve of current vs. concentration.

Connecting to Theory: Michaelis-Menten Kinetics
The sensor’s response isn’t just linear; it’s governed by the enzyme kinetics. At low concentrations, the response is linear. At higher concentrations, the enzyme becomes saturated, and the signal begins to plateau.

This behavior is perfectly described by the Michaelis-Menten equation. Students can use their data to:

  • Identify the maximum reaction rate (V_max).

  • Calculate the K_m (Michaelis constant), the concentration at which the reaction rate is half of V_max.

This practical lab brilliantly ties a core biochemistry concept to a real-world engineering application.

Lab 2: The Potassium Sensor (Open-Circuit Potentiometry – OCP)

The Principle:
Potassium sensors are a type of ion-selective electrode (ISE). The sensor’s surface is functionalized to be specifically selective to potassium ions (K⁺). The working electrode develops a potential relative to the reference electrode based on the concentration of K⁺ ions in the solution.

The potential change follows a Nernstian relationship: for a perfect K⁺ sensor, a ten-fold change in concentration results in a 59 mV change in potential at room temperature.

The Teaching Demo:
Switching from glucose to potassium is seamless with the SenseItAll (SIA) platform:

  1. Scan a new QR code to switch the meter to OCP mode.

  2. Place a potassium-specific sensor strip.

  3. Add a baseline buffer solution and start the measurement.

  4. Add a known concentration of potassium analyte. The potential will shift immediately.

  5. The data is again sent to the cloud for analysis.

Students can add incremental amounts of potassium, plot the potential against the logarithm of the concentration, and calculate the actual slope of their sensor’s response, comparing it to the ideal Nernstian value.

The SenseItAll (SIA) Teaching Platform: How It Works

The demos highlighted the simplicity of the modern teaching stack:

  1. The Hardware: Pre-functionalized, ready-to-use sensor strips.

  2. The Meter: A compact, cable-free device controlled via Bluetooth.

  3. The App: The SenseItAll (SIA) app uses QR codes to automatically configure the meter for the correct experiment (amperometry or OCP).

  4. The Cloud: Data is uploaded instantly to the cloud (the Djuli software platform), where students and instructors can access, visualize, and analyze results from any device.

This integrated system removes the traditional friction of complex cabling and software setup, allowing students to focus on the science, not the setup. Sensors can also be washed and reused for multiple experiments.

Summary: Bringing Theory to Life

Teaching biomedical engineering through biosensors provides an unmatched practical experience. Starting with robust and clinically relevant examples like glucose and potassium sensors allows students to:

  • Master fundamental electrochemical techniques (amperometry, OCP).

  • Understand critical theoretical models (Michaelis-Menten kinetics, Nernst equation).

  • Work with a modern, cloud-connected data acquisition system.

  • Appreciate the truly interdisciplinary nature of their field.

ZP Technologies provides a complete platform—sensors, hardware, software, and curriculum support—to make integrating these powerful labs into undergraduate teaching simple and effective.

Ready to bring hands-on biosensing into your lab? Reach out to us to learn more about the SenseItAll (SIA) teaching platform and how it can transform your biomedical engineering curriculum.