Applications

AFM in life science education

We are convinced that our AFMs have a key role to play in education, thanks to their simple operation, open-source design, affordability, and low maintenance requirements. We have taught many students as early as high school and community college to operate our AFMs. Contact us, we’re excited to show you how!

Today, AFMs are the simplest, most affordable, versatile tool to discover, understand, and control biomaterials at the nanoscale.

Many concepts in cell biology, microbiology, molecular biology, and medicine have been out of reach for hands-on learning experiences in high school and college. The traditional light microscopes used to study cells and tissues are affordable but limited in resolution. Electron microscopes that can achieve molecular resolution are too expensive, complex and the standard methods are too toxic to be put in the hands of inexperienced students. The result is that students learn about subcellular concepts such as organelles, many microbes, and molecules from vastly oversimplified schematic drawings in textbooks. There is as much biology between the millimeter and the micrometer as between the micrometer and the nanometer, but very few people ever get access to the latter.

We are convinced that our AFMs have a key role to play in education, thanks to their simple operation, open-source design, affordability, and low maintenance requirements. We have taught many students as early as high school and community college to operate our AFMs. And when it comes to use-inspired research, we can only use and be inspired by what we know!1

Today, AFMs are the simplest, most affordable, versatile tool to discover, understand, and control biomaterials at the nanoscale.

Inspiration

We all know that inspiration in STEM education comes from students being able to do a project with their own hands and discover science for themselves. This seems impossible for the field of nanobiology, but it’s very doable! And it can be done gradually. Let me illustrate.

The protocol begins with having a sample to image, ideally something that is familiar and at the same time scientifically relevant. You don’t have that for nanobiology? Meet the eggshell membrane, which everyone has at some point peeled off a hard-boiled egg. The eggshell membrane consists largely of collagen I fibers that denature during the boiling process.2 Comparing these samples teaches about cell biology at the microscale, protein denaturation, AFM theory and data analysis. These samples and 50×50 µm images can be obtained by a student after a few hours of training using a $30,000 AFM, a $20 AFM probe and a few consumables (including the egg!) without the use of any chemicals. The worst outcome is a broken probe.

Eggshell membrane peeled from a hard-boiled egg, dried and mounted with double-sided tape and imaged with a standard AFM probe, showing lots of spherical features with hints of filaments (topography, 50x50x1.3 µm volume).

Fresh eggshell membrane facing the egg white. The eggshell with the membrane attached was rinsed, dried and mounted with double-sided tape, and imaged with a standard AFM probe. The network of collagen I fibers gives the membrane its mechanical properties (topography, 50x50x1.1 µm volume).

We can push this project further by analyzing the eggshell membrane in other locations, such as adjacent to the air pocket where the membrane is not supported by the shell and accordingly shows a denser collagen network.

Fresh eggshell membrane showing the denser collagen network facing the air pocket (topography, 15x15x2.26 µm volume).

How about the nanoscale? We can do that too! It turns out that the eggshell membrane that is facing the egg white is still covered in egg white proteins, 54% of which are ovalbumin.3 Ovalbumin is about 43 kDa and 7×3.6×3 nm in size.4

Egg white proteins covering the eggshell membrane, imaged with a standard AFM probe with <10 nm tip radius (topography, 2×0.8 µm x 2.89 nm volume).

The same image as above rendered and shadowed for 3D representation.

More examples

Ok, the eggshell membrane is fun, what else? How about bacteria cultured on an agar plate from biotechnology class? Human microbiomes? Red blood cells? Paper, a biomaterial turned into a nanomaterial? Contact us with more ideas!

Oral microbiome, an epithelial cell from a cheek swab with bacteria on its ruffled surface.

Bacterial colony picked from an agar plate.

Red blood cells, embedded in coagulated blood proteins.

The surface of a biomaterial, plain printer paper, with embedded cellulose fibers.

The surface of glossy photo paper for inkjet printers, a nanomaterial on a biomaterial backing (the paper). This can be used to illustrate the measurement of nanoparticles (~10-20 nm in this example).

Requirements and costs

To put it in perspective, you can run all these experiments above in your garage, on an AFM that costs as much as an average new car, without maintenance contracts, and a few thousand dollars in annual consumables (mostly probes). Yes, nanotechnology in your garage, check! You need about 3×3 feet of floor space away from active sources of vibrations (freezers, centrifuges, hallways, roads, …) and a desk for 1-2 PC monitors, ideally bench space nearby to prepare samples, and a 110V outlet.

For education, the most important piece is developing a great curriculum that aligns with things that students learn during lectures and maybe work with in labs, and that create an iterative loop of design – synthesis – analysis – repeat.

We are excited to support educational programs in any stage, demonstrations, curriculum development, grants writing, to instrument sales. Don’t hesitate to contact us, we are here to help!

References