Dear friend Adina Bleil

Specific information on "how to make a hydrogel with a Young's Modulus of 0.2 kPa" is not available. Let us try to find the possible answer of your question. Let us start with a paper that describes a universal strategy for preparing tough and stretchable hydrogels by tuning the polymerization conditions to form networks with many polymer chain entanglements to achieve energy dissipation. Tough and stretchable hydrogels can be prepared by free radical polymerization with a high monomer concentration and low cross-linker content to optimize the balance between physical and chemical cross-links by entanglements and covalent bonds, respectively (https://www.nature.com/articles/s41427-021-00302-2).

I also found the paper you mentioned, "Mechano-responsiveness of fibrillar adhesions on stiffness-gradient gels," which describes a cost-effective and reproducible technique to fabricate physiologically relevant stiffness gradients on thin polyacrylamide (PA) hydrogels, embedded with fluorescently labeled beads. They generated a correlation curve between bead density and hydrogel stiffness, thus enabling a readout of stiffness without the need for specialized know-how, such as atomic force microscopy (AFM) (Article Engineering hydrogels with homogeneous mechanical properties...

Let us keep in touch and see how we can solve this question together.

I suggest exploring the following references.

Source:

(1) A universal method to easily design tough and stretchable ... - Nature. https://www.nature.com/articles/s41427-021-00302-2.

(2) Mechano-responsiveness of fibrillar adhesions on stiffness-gradient gels. https://journals.biologists.com/jcs/article/133/12/jcs242909/224061/Mechano-responsiveness-of-fibrillar-adhesions-on.

(3) Elastic Modulus Measurement of Hydrogels | SpringerLink. https://link.springer.com/referenceworkentry/10.1007/978-3-319-76573-0_60-1.

(4) Engineering hydrogels with homogeneous mechanical properties for ... - PNAS. https://www.pnas.org/doi/10.1073/pnas.2110961118.