The team at the Technological University, Singapore (NTU Singapore)–CEA Alliance for Research in Circular Economy (SCARCE) only subjected plastic e-waste to sterilisation before being trialled in lab experiments.
The team found that over 95 per cent of the human stem cells seeded on plastics scavenged from discarded computer components remained healthy after a week, which is comparable to cells grown on conventional cell culture plates.
These findings, described online in Science of the Total Environment, indicate a potential new sustainable use for e-waste plastics, which account for about 20 per cent of the 50 million tonnes of e-waste produced globally. On the laboratory side, around 5.5 million tonnes of plastic waste, including cell culture dishes, is generated worldwide in a year.
Team leader Assistant Professor Dalton Tay of the NTU School of Materials Science and Engineering and School of Biological Sciences, said: “E-waste plastics contain hazardous components which may get released into the environment if not disposed of properly. Interestingly, we found through our studies that certain e-waste plastics could successfully maintain cell growth, making them potential alternatives to the cell culture plastics used in labs today.”
“Repurposing them for immediate use rather than recycling them enables the immediate extension of the lifespan of e-waste plastics and minimises environmental pollution. Our approach is in line with the zero-waste hierarchy framework, which prioritises the reuse option through materials science and engineering innovation.”
For their study, the NTU team used plastic from e-waste collected by a local waste recycling facility. Three kinds of e-waste plastic were chosen for their varied surface features – the keyboard pushbuttons and diffuser sheet obtained from LCDs have a relatively flat and smooth surface, while the prism sheet, also found in LCDs, has highly aligned ridges.
To test the viability of using e-waste plastics for cell cultures, the NTU team seeded stem cells onto 1.1cm-wide circular discs of sterilised e-waste plastics.
A week later, the scientists found that more than 95 per cent of live and healthy stem cells seeded on the e-plastics remained, which is comparable to the experimental control of stem cells grown on commercially available cell culture plates made of polystyrene.
The stem cells grown on the e-waste plastics also retained their ability to differentiate, described by NTU Singapore as a process in which stem cells become specialised cells with a more specific function.
Asst Prof Tay said: “In tissue engineering, we use advanced techniques to engineer surfaces and study how they can influence stem cell differentiation. Now, we have shown that e-waste plastics are a ready source of such microstructures that allow us to further study how stem cell development can be directed – the ‘holy grail’ of regenerative medicine and more recently, lab-grown meat. There are important biomaterials and scaffold design rules and lessons we can learn from these e-waste plastic scraps.”