Technology & solutions
Biomedical market sees 
in-mold printed electronics
-Biomedical market sees in-mold printed electronics
San Diego — Karthik Gopalan discussed the use of printed, flexible and in-mold electronics for biomedical applications.
The fourth-year doctorate candidate and researcher at the University of California, Berkeley’s electrical engineering and computer sciences department compared the value of additive printing — “one step for patterning and deposition” — vs. multi-step photolithography.
For wound monitoring, inkjet-printed electrode arrays can map tissue impedance and detect wounds such as pressure ulcers before they become visible, Gopalan said, citing two 2015 technical papers.
Impedance mapping can extract unique electrical signatures in healthy and damaged tissue, he noted in remarks at the IMDA symposium.
InkSpace Imaging Inc., a spinoff from the UC Berkeley laboratory of professor Ana Claudia Arias is making technology strides. Arias is advising Gopalan.
Startup InkSpace of Moraga, Calif., can use additive processing in making patient-customized lightweight magnetic resonance imaging surface-receive coils that can increase patient comfort and the speed of examinations.
InkSpace’s manufacturing method uses printed electronics to make extremely lightweight, flexible and low-cost MRI coils.
In particular, printed coils can benefit pediatric patients and limit the use of general anesthesia.
“The mission is to make body coils to fit any patient’s size, shape or body part,” Gopalan said.
InkSpace’s MRI surface technology adds to the functionality of organic optoelectronics for pulse oximetry from suppliers such as Cambridge Display Technology Ltd. of Godmanchester, England, or Intel Corp. of Santa Clara, Calif. An oximeter measures the oxygen saturation of arterial blood in a subject.
An adaptable model 300XQ vacuum forming machine from Formech International Ltd. of Harpenden, England, is used in processing plastic sheet modeled on a grid of points with finite mass. Adjacent points are coupled with “springs,” infinite friction is set between the plastic and the mold and the vacuum force is proportional to the area of each triangle, Gopalan said, quoting from two other technical papers.
“You need to predistort the plastics before the cloth is draped over,” Gopalan said.
Project leaders aim to enter a production phase in mid-2019 in conjunction with custom injection molder Sussex IM Inc. of Sussex, Wis.
For the technology developments, the National Science Foundation has awarded two Small Business Innovation Research grants to InkSpace: $224,980 in 2017 and $750,000 in 2018.
Gopalan acknowledged technical contributions from others at UC Berkeley for scanning, ink selection and spray coating support; Xerox Corp.’s Palo Alto Research Center for help with electro-less plating; Formech for research and technical assistance; and Massachusetts General Hospital.
