Science News
from research organizations

Ultrafast lasers offer 3-D micropatterning of biocompatible hydrogels

Technique provides high resolution, scalability for tissue scaffolds and implants

Date:
September 23, 2015
Source:
Tufts University
Summary:
Low-energy, ultrafast laser technology is able to make high-resolution, 3-D structures in transparent silk protein hydrogels to support cell growth and allow cells to penetrate deep within the material. The work represents a new approach to customized engineering of tissue and biomedical implants. Its efficacy was shown in vivo and in vitro.
Share:
FULL STORY

Illustration of laser-based micropatterning of silk hydrogels. The transparent gels enable the laser's photons to be absorbed more than 10 times deeper than with other materials, without damaging the cells surrounding the "Tufts" pattern.
Credit: Courtesy: M.B. A

Tufts University biomedical engineers are using low-energy, ultrafast laser technology to make high-resolution, 3-D structures in silk protein hydrogels. The laser-based micropatterning represents a new approach to customized engineering of tissue and biomedical implants.

The work is reported in a paper in PNAS Early Edition published September 15 online before print: "Laser-based three-dimensional multiscale micropatterning of biocompatible hydrogels for customized tissue engineering scaffolds."

Artificial tissue growth requires pores, or voids, to bring oxygen and nutrients to rapidly proliferating cells in the tissue scaffold. Current patterning techniques allow for the production of random, micron-scale pores and the creation of channels that are hundreds of microns in diameter, but there is little in between.

The Tufts researchers used an ultrafast, femtosecond laser to generate scalable, high-resolution 3-D voids within silk protein hydrogel, a soft, transparent biomaterial that supports cell growth and allows cells to penetrate deep within it. The researchers were able to create voids at multiple scales as small as 10 microns and as large at 400 microns over a large volume.

Further, the exceptional clarity of the transparent silk gels enabled the laser's photons to be absorbed nearly 1 cm below the surface of the gel -- more than 10 times deeper than with other materials, without damaging adjacent material.

The laser treatment can be done while keeping the cell culture sealed and sterile. Unlike most 3-D printing, this technique does not require photoinitiators, compounds that promote photoreactivity but are typically bio-incompatible.

"Because the femtosecond laser pulses allow us to target specific regions without any damage to the immediate surroundings, we can imagine using such micropatterning to controllably design around living cells, guide cell growth and create an artificial vasculature within an already densely seeded silk hydrogel," said senior author Fiorenzo G. Omenetto, Ph.D. Omenetto is associate dean for research, professor of biomedical engineering and Frank C. Doble professor at Tufts School of Engineering and also holds an appointment in physics in the School of Arts and Sciences.

The research team reported similar results in vitro and in a preliminary in vivo study in mice.

Other authors on the paper were Matthew B. Applegate, who led the experimental effort; Jeannine Coburn; Benjamin P. Partlow; Jodie E. Moreau; Jessica P. Mondia; Benedetto Marelli, and David L. Kaplan, all of the Department of Biomedical Engineering, Tufts University School of Engineering.

The study received funding from the Office of Naval Research.


Story Source:

Materials provided by Tufts University. Note: Content may be edited for style and length.


Journal Reference:

  1. Matthew B. Applegate, Jeannine Coburn, Benjamin P. Partlow, Jodie E. Moreau, Jessica P. Mondia, Benedetto Marelli, David L. Kaplan, Fiorenzo G. Omenetto. Laser-based three-dimensional multiscale micropatterning of biocompatible hydrogels for customized tissue engineering scaffolds. Proceedings of the National Academy of Sciences, 2015; 201509405 DOI: 10.1073/pnas.1509405112

Cite This Page:

Tufts University. "Ultrafast lasers offer 3-D micropatterning of biocompatible hydrogels: Technique provides high resolution, scalability for tissue scaffolds and implants." ScienceDaily. ScienceDaily, 23 September 2015. <www.sciencedaily.com/releases/2015/09/150923134205.htm>.
Tufts University. (2015, September 23). Ultrafast lasers offer 3-D micropatterning of biocompatible hydrogels: Technique provides high resolution, scalability for tissue scaffolds and implants. ScienceDaily. Retrieved May 24, 2017 from www.sciencedaily.com/releases/2015/09/150923134205.htm
Tufts University. "Ultrafast lasers offer 3-D micropatterning of biocompatible hydrogels: Technique provides high resolution, scalability for tissue scaffolds and implants." ScienceDaily. www.sciencedaily.com/releases/2015/09/150923134205.htm (accessed May 24, 2017).

RELATED STORIES