Hi Elnaz Ahani

These references could help you

1. Stiffness and adhesivity control aortic valve interstitial cell behavior within hyaluronic acid based hydrogels

By BinDuanaLaura A.HockadayaEdiKapetanovicbKevin H.KangaJonathan T.Butchera

2. Elucidating the mechanobiology of malignant brain tumors using a brain matrix-mimetic hyaluronic acid hydrogel platform

By Badriprasad Ananthanarayanana Yushan KimabSanjay Kumarab

3. Design of Biomimetic Cell-Interactive Substrates Using Hyaluronic Acid Hydrogels with Tunable Mechanical Properties

4. The influence of hyaluronic acid hydrogel crosslinking density and macromolecular diffusivity on human MSC chondrogenesis and hypertrophy

@Ibtisam Abbas many thanks your response

@Qifeng Mu many thanks for your response

If you need to know the overall stiffness of your hydrogel (i.e. scaffold), then you can try by means of a texture analyzer.

In case you want to know how your cells "sense" each particular point of your substrate, then you can go with AFM and extract the Young’s Moduli from nanoindentation curves and Hertz model fitting, just as they told you before.

many thanks for your response

Hi Elnaz, Here is a good reference to investigate the mechanical properties of hydrogels.

https://www.oulu.fi/spareparts/ebook_topics_in_t_e_vol4/abstracts/ahearne.pdf

Best of luck

Hi ELnaz,

You can meaure the stiffness of your hydrogels by performing oscillatory rheological measurements of the elastic modulus G΄ and the viscous modulus G΄΄ as function of shear strain (Amplitude sweep experiment) and as function of frequency (Frequency sweep experiment). The amplitude sweep experiment will help you to determine the linear viscoelastic region (LVR) of deformation of hydrogels at increasing shear strains. Then you apply a strain value within the LVR to the frequency sweep experiment. You can also advise the following papers for your reference:

• Oyen M.L., Mechanical characterisation of hydrogel materials, Int. Mater. Rev., 2014, 59, 44-59.
• Cheng S., Clarke E.C.,Bilston L.E., Rheological properties of the tissues of the central nervous system: A review, Med. Eng. Phys., 2008, 30, 1318-1337.
• Zuidema J., Rivet C., Gilbert R., Morrison F., A protocol for rheological characterization of hydrogels for tissue engineering strategies, J. Biomed. Mater. Res. B Appl. Biomater., 2014, 102, 1063-1073.

Hi Elnaz Ahani

you can use universal testing machine(UTM) with 50 N load cell and with slow frequency. please check this paper for details.

Article Bi-functional oxidized dextran–based hydrogel inducing micro...

Look for gel bloom test.

Contact Fabien, he's specialist

I would like to recommend you a paper, good luck.

Article Multi-modal characterization of polymeric gels to determine ...

hi

before measure any stiffness, my suggestion is draw a table for designing your experiments. use DX software. after that as last comments, you can use universal testing machine(UTM).

Have a look at this chapter, you may find your solution: Chapter Elastic Modulus Measurement of Hydrogels