Bioactive polyacrylamide hydrogels with gradients in mechanical stiffness

V. E. G. Diederich, P. Studer, A. Kern, M. Lattuada, G. Storti, R.I. Sharma, J.G. Snedeker, M. Morbidelli

Research output: Contribution to journalArticle

17 Citations (Scopus)

Abstract

We propose a novel, single step method for the production of polyacrylamide hydrogels with a gradient in mechanical properties. In contrast to already existing techniques such as UV photo-polymerization with photomasks (limited penetration depth) or microfluidic gradient mixers (complex microfluidic chip), this technique is not suffering such limitations. Young's modulus of the hydrogels was varied by changing the total monomer concentration of the hydrogel precursor solution. Using programmable syringe pumps, the total monomer concentration in the solution fed to the hydrogel mold was varied from 16wt% down to 5wt% over the feeding time to obtain a gradient in compliance ranging from 150kPa down to 20kPa over a length of 10mm down to 2.5mm. Polymerization was achieved with the dual initiation system composed of ammonium persulfate and N,N,N′,N′-tetramethylethylenediamine, which were both fed through separate capillaries to avoid premature polymerization. Functionalized with the model ligand collagen I, the substrates were bioactive and supported the attachment of human foreskin fibroblasts (around 30% of the cells seeded attached after 1h). A kinetic morphology study on homogeneous hydrogels of different stiffness's indicated that fibroblasts tend to spread to their final size within 2h on stiff substrates, while the spreading time was much longer (ca. 4-5h) on soft substrates. These trends were confirmed on hydrogels with compliance gradients, showing well spread fibroblasts on the stiff end of the hydrogel after 2h, while the cells on the soft end still had small area and rounded morphology.
Original languageEnglish
Pages (from-to)1508-1519
JournalBiotechnology and Bioengineering
Volume110
Issue number5
Early online date4 Jan 2013
DOIs
Publication statusPublished - May 2013

Fingerprint

Hydrogels
Hydrogel
Fibroblasts
Polyacrylates
Polymerization
Microfluidics
Stiffness
Compliance
Substrates
Monomers
Foreskin
Syringes
Photomasks
Photopolymerization
Elastic Modulus
Fungi
Collagen
Elastic moduli
Pumps
Ligands

Cite this

Diederich, V. E. G., Studer, P., Kern, A., Lattuada, M., Storti, G., Sharma, R. I., ... Morbidelli, M. (2013). Bioactive polyacrylamide hydrogels with gradients in mechanical stiffness. Biotechnology and Bioengineering, 110(5), 1508-1519. https://doi.org/10.1002/bit.24810

Bioactive polyacrylamide hydrogels with gradients in mechanical stiffness. / Diederich, V. E. G.; Studer, P.; Kern, A.; Lattuada, M.; Storti, G.; Sharma, R.I.; Snedeker, J.G.; Morbidelli, M.

In: Biotechnology and Bioengineering, Vol. 110, No. 5, 05.2013, p. 1508-1519.

Research output: Contribution to journalArticle

Diederich, VEG, Studer, P, Kern, A, Lattuada, M, Storti, G, Sharma, RI, Snedeker, JG & Morbidelli, M 2013, 'Bioactive polyacrylamide hydrogels with gradients in mechanical stiffness', Biotechnology and Bioengineering, vol. 110, no. 5, pp. 1508-1519. https://doi.org/10.1002/bit.24810
Diederich VEG, Studer P, Kern A, Lattuada M, Storti G, Sharma RI et al. Bioactive polyacrylamide hydrogels with gradients in mechanical stiffness. Biotechnology and Bioengineering. 2013 May;110(5):1508-1519. https://doi.org/10.1002/bit.24810
Diederich, V. E. G. ; Studer, P. ; Kern, A. ; Lattuada, M. ; Storti, G. ; Sharma, R.I. ; Snedeker, J.G. ; Morbidelli, M. / Bioactive polyacrylamide hydrogels with gradients in mechanical stiffness. In: Biotechnology and Bioengineering. 2013 ; Vol. 110, No. 5. pp. 1508-1519.
@article{1db483dc99e8462c986dcfb4d7d9de17,
title = "Bioactive polyacrylamide hydrogels with gradients in mechanical stiffness",
abstract = "We propose a novel, single step method for the production of polyacrylamide hydrogels with a gradient in mechanical properties. In contrast to already existing techniques such as UV photo-polymerization with photomasks (limited penetration depth) or microfluidic gradient mixers (complex microfluidic chip), this technique is not suffering such limitations. Young's modulus of the hydrogels was varied by changing the total monomer concentration of the hydrogel precursor solution. Using programmable syringe pumps, the total monomer concentration in the solution fed to the hydrogel mold was varied from 16wt{\%} down to 5wt{\%} over the feeding time to obtain a gradient in compliance ranging from 150kPa down to 20kPa over a length of 10mm down to 2.5mm. Polymerization was achieved with the dual initiation system composed of ammonium persulfate and N,N,N′,N′-tetramethylethylenediamine, which were both fed through separate capillaries to avoid premature polymerization. Functionalized with the model ligand collagen I, the substrates were bioactive and supported the attachment of human foreskin fibroblasts (around 30{\%} of the cells seeded attached after 1h). A kinetic morphology study on homogeneous hydrogels of different stiffness's indicated that fibroblasts tend to spread to their final size within 2h on stiff substrates, while the spreading time was much longer (ca. 4-5h) on soft substrates. These trends were confirmed on hydrogels with compliance gradients, showing well spread fibroblasts on the stiff end of the hydrogel after 2h, while the cells on the soft end still had small area and rounded morphology.",
author = "Diederich, {V. E. G.} and P. Studer and A. Kern and M. Lattuada and G. Storti and R.I. Sharma and J.G. Snedeker and M. Morbidelli",
year = "2013",
month = "5",
doi = "10.1002/bit.24810",
language = "English",
volume = "110",
pages = "1508--1519",
journal = "Biotechnology and Bioengineering",
issn = "0006-3592",
publisher = "Wiley-VCH Verlag",
number = "5",

}

TY - JOUR

T1 - Bioactive polyacrylamide hydrogels with gradients in mechanical stiffness

AU - Diederich, V. E. G.

AU - Studer, P.

AU - Kern, A.

AU - Lattuada, M.

AU - Storti, G.

AU - Sharma, R.I.

AU - Snedeker, J.G.

AU - Morbidelli, M.

PY - 2013/5

Y1 - 2013/5

N2 - We propose a novel, single step method for the production of polyacrylamide hydrogels with a gradient in mechanical properties. In contrast to already existing techniques such as UV photo-polymerization with photomasks (limited penetration depth) or microfluidic gradient mixers (complex microfluidic chip), this technique is not suffering such limitations. Young's modulus of the hydrogels was varied by changing the total monomer concentration of the hydrogel precursor solution. Using programmable syringe pumps, the total monomer concentration in the solution fed to the hydrogel mold was varied from 16wt% down to 5wt% over the feeding time to obtain a gradient in compliance ranging from 150kPa down to 20kPa over a length of 10mm down to 2.5mm. Polymerization was achieved with the dual initiation system composed of ammonium persulfate and N,N,N′,N′-tetramethylethylenediamine, which were both fed through separate capillaries to avoid premature polymerization. Functionalized with the model ligand collagen I, the substrates were bioactive and supported the attachment of human foreskin fibroblasts (around 30% of the cells seeded attached after 1h). A kinetic morphology study on homogeneous hydrogels of different stiffness's indicated that fibroblasts tend to spread to their final size within 2h on stiff substrates, while the spreading time was much longer (ca. 4-5h) on soft substrates. These trends were confirmed on hydrogels with compliance gradients, showing well spread fibroblasts on the stiff end of the hydrogel after 2h, while the cells on the soft end still had small area and rounded morphology.

AB - We propose a novel, single step method for the production of polyacrylamide hydrogels with a gradient in mechanical properties. In contrast to already existing techniques such as UV photo-polymerization with photomasks (limited penetration depth) or microfluidic gradient mixers (complex microfluidic chip), this technique is not suffering such limitations. Young's modulus of the hydrogels was varied by changing the total monomer concentration of the hydrogel precursor solution. Using programmable syringe pumps, the total monomer concentration in the solution fed to the hydrogel mold was varied from 16wt% down to 5wt% over the feeding time to obtain a gradient in compliance ranging from 150kPa down to 20kPa over a length of 10mm down to 2.5mm. Polymerization was achieved with the dual initiation system composed of ammonium persulfate and N,N,N′,N′-tetramethylethylenediamine, which were both fed through separate capillaries to avoid premature polymerization. Functionalized with the model ligand collagen I, the substrates were bioactive and supported the attachment of human foreskin fibroblasts (around 30% of the cells seeded attached after 1h). A kinetic morphology study on homogeneous hydrogels of different stiffness's indicated that fibroblasts tend to spread to their final size within 2h on stiff substrates, while the spreading time was much longer (ca. 4-5h) on soft substrates. These trends were confirmed on hydrogels with compliance gradients, showing well spread fibroblasts on the stiff end of the hydrogel after 2h, while the cells on the soft end still had small area and rounded morphology.

UR - http://www.scopus.com/inward/record.url?scp=84875527562&partnerID=8YFLogxK

UR - http://dx.doi.org/10.1002/bit.24810

U2 - 10.1002/bit.24810

DO - 10.1002/bit.24810

M3 - Article

VL - 110

SP - 1508

EP - 1519

JO - Biotechnology and Bioengineering

JF - Biotechnology and Bioengineering

SN - 0006-3592

IS - 5

ER -