Bio-Inspired Nanotextiles

Overview

A new technique of nanofiber fabrication using the rotary jet spinning for regenerative medicine and other industrial applications
A mathematical model of rotary jet spinning to predict fiber diameter under different processing conditions
Manufacturing protein nanoFabrics using extracellular matrix proteins

A new technique of nanofiber fabrication using the rotary jet spinning for regenerative medicine and other industrial applications

Primary Investigator: Mohammad R. Badrossamay, Ph.D

We have developed an effective technique for the generation of continuous ﬁbers and non-woven fabrics with nanometer size ﬁber diameters by using high-speed mechanical rotation of polymeric solutions through a perforated rotary reservoir. Termed, Rotary jet-spinning (RJS), has several advantages in comparison with other nanofiber fabrication methods: (a) the technique does not require high-voltage electric fields, (b) the apparatus is simple to implement, (c) nanofiber structures can be fabricated into an aligned 3D structure or any arbitrary shape by varying the collector geometry, (d) ﬁber morphology (beaded, textured, or smooth), ﬁber diameters, and web porosity can be manipulated by altering the process variables, (e) ﬁber fabrication is independent of solution conductivity, (f) RJS is easily applicable to polymer emulsions and suspensions, and (g) RJS is capable of substantially higher production rates as compared to standard electrospinning.

FIGURE: Schematic of rotary jet-spinning (RJS) system
A: Rotary jet spinning is capable of forming 3D structures with any arbitrary shape.
B: Scanning electron micrographs of smooth nanofibers (C), decorated (D) and textured (E).

A mathematical model of rotary jet spinning to predict fiber diameter under different processing conditions

Primary Investigator: Holly McIlwee

Currently we are studying the formation of nanofibers being produced in our lab via Rotary Jet Spinning from a physical point of view. Using the tools of fluidynamics, we have computed scaling laws that permit us to decrease the diameter and at the same time ensure the continuity of nanofibers, in terms of a few set of tunable laboratory parameters. These scaling laws can be easily translated into phase diagrams for obtaining fibers of desirable characteristics, when design and solution parameters fall into a well defined range.

FIGURE: Three stages of fiber formation in Rotary Jet-Spinning.
A: Jet initiation
B: Jet elongation
C: Solvent evaporation
D: Movie shows nanofiber formation by Rotary Jet-Spinning (RJS) captured by high speed camera

Manufacturing protein nanoFabrics using extracellular matrix proteins for applications ranging from biophotonic devices to neuronal tissue engineering

Primary Investigator: Leila Deravi, Ph.D

We have developed a technique for manufacturing bio-inspired nanoFabrics using the model protein Fibronectin (FN). FN nanoFabrics are synthesized using micro-contact printing onto thermosensitive, polymer substrates. At low temperatures (T< 32ºC), the polymer substrate dissolves, and our pre-patterned protein pops off the substrate as free-standing fibrillar networks, or nanoFabrics. When relaxed FN nanoFabrics are mechanically strained, they exhibit a 6-fold extension without failure, likely due to protein extension under strain. By identifying how mechanical strain affects protein conformation within fabrics, we can begin to design a new range of hyper-elastic textiles with similar chemical properties.

FIGURE: Manufacturing FN nanoFabrics.
A: We built FN networks in the form of nanometer thick fabrics by releasing micropatterned FN from a thermosensitive substrate. Scale bar 20 µm.
B: Atomic force micrograph of FN nanoFabrics after release demonstrates nanoscale thickness.
C: Scanning electron micrograph of FN nanoFabrics after release demonstrates millimeter scale dimensions. Scale bar 50 µm.

What's New

Picture of the Month – April 2012 April 6th, 2012

Isotropic cardiac myocyte monolayer stained for actin (red), beta-catenin (white), and nuclear DNA (blue). Image by Megan McCain, Parker lab.

Congrats to Kartik Balachandran! March 14th, 2012

Kartik Balachandran has been awarded the Postdoctoral Fellow Best Abstract Award by the Association of Scientists of Indian Origin Special Interest Group of the Society of Toxicology (SOT) at the SOT Annual Meeting in San Francisco, CA. This competitive award was based on a submitted abstract and a cover letter outlining the significance of his research. The award includes a plaque and monetary award of $500. Congratulations, Kartik!!

Congrats to Josh Goss!! March 5th, 2012

Josh Goss is one of the winners of the first Harvard School of Engineering and Applied Sciences Dean’s Excellence Award. Josh is the senior instrumentation engineer and staff scientists in the Disease Biophysics Group, designing and prototyping all of our experimental systems from microfluidic systems for organs on chips to blast bioreactors for brain injury research. Congratulations, Josh!! Thanks for all of your hard work!!

Picture of the Month – February 2012 February 24th, 2012

Micropatterned mouse ventricular muscle cells assembled into an anisotropic tissue showing nuclei (pink) and organized sarcomeres (orange). This organization recapitulates features of the native architecture of cardiac tissue. Image by Anna Grosberg, Parker lab.

Postdoctoral Positions in the DBG February 19th, 2012

We have several postdoctoral positions opening now and in the coming months. We are especially interested in candidates with backgrounds in theoretical biomechanics who are interested in conducting bench experiments. These positions will focus on our efforts to recapitulate organ-level function on chips for drug discovery and safety pharmacology.

All of these positions require a doctoral degree in an appropriate field and a demonstrated publication record. Applications in the form of a single PDF file containing a cover letter, resume, and up to three examples of first author papers should be forwarded to Prof Parker (kkparker@seas.harvard.edu). A list of references should be submitted with the resume with contact information.