Back in 2015, the discovery of lead in a public estate’s drinking water sparked public concerns over the adverse affects on people’s health. Inspired by the incident, 39 students from five local secondary schools teamed up to create a device that could lower the copper-ion concentration in aquaponics (any system that combines raising aquatic animals and cultivating plants in water).
A similar project was previously done by their seniors in 2016, which the team of students from the joint school alliance, Hong Kong JSS, improved upon. This time around, they used genetically modified E. coli – a bacteria commonly found in human and animal intestines – to absorb copper ions in aquaponics.
In early November, 30 of the members flew to Boston in the United States to present their idea at the International Genetically Engineered Machine Competition, an annual worldwide event that gathers young biology talents across the globe and their innovative solutions to everyday problems.
The team’s experimental design and findings made them the first secondary school team in Hong Kong to win a gold medal.
Young Post sat down with three of the team members last week to learn more about their project and their eye-opening overseas learning experience.
“We’ve taken a lot of water samples from different aquaponic systems, from which we detected a high concentration of copper,” says team leader Yoyo Yip Sze-man, 16.
They chose to fix this problem for their project mainly because they already had access to something that could help them detect and measure the amount of copper in water, said the PLK Celine Ho Yam Tong College student.
She adds that they hoped the technology they came up with could be used to remove other heavy metal pollutants found in water.
The students from PLK Celine Ho Yam Tong College, United Christian College (Kowloon East), Yan Oi Tong Tin Ka Ping Secondary School, Po Leung Kuk Celine Ho Yam Tong College, Pentecostal School, and St Teresa Secondary School split up into smaller school teams led by their respective biology teachers.
Some were in charge of developing, testing and evaluating their hypotheses, while other took to the street to raise awareness of the hazards of water contaminated with heavy metals, and surveyed different people in the aquaponics industry.
The team discovered that E. coli could better absorb copper if they increased its copper binding proteins, and got rid of the genes that produced copper. In light of this discovery, they then developed their bacteria copper absorption device (B-cad) that incorporated the two types of genetically modified bacteria.
The B-cad has artificial tubes that could take in copper ions and not let out E. coli. The resulting device is able to remove 25-55 per cent of the copper in a aquaphonic system with 5-15mg/L copper ion in 48 hours.
“After consulting fish owners and potential users of the device, we added a cage around the [tubes] to prevent them from being bitten off by fish, which could potentially fall ill if the bacteria was leaked to their habitats,” says Yoyo.
A magnetic stirrer was also installed to the B-cad device to prevent the E. coli from sedimenting, to ensure it continues to remove copper efficiently, she adds.
When asked what their most memorable challenge was, Jasmine Yu On-yi, 16, recalls the times she and her teammates had to stay in school until 8pm.
“Since our experimental results deviated from what we’d expected, we [had to repeat] the same experiment – which takes about four hours to complete – after school about three to four times in total,” said the Yan Oi Tong Tin Ka Ping student.
“The journey was quite distressing.”
Looking back, though, both Jasmine and Yoyo are grateful to have overcome all the challenges that they came across.
“[We got] a great sense of satisfaction when we finally succeeded in the end,” explains Yoyo.
Yoyo adds that while biology classes are mainly theoretical, the hands-on experience the project gave her enabled her to “gain a more thorough understanding of the science behind the experiments, such as the different conditions and human errors that would alter the results.”
Unlike the girls, Pentecostal School’s Oscar Lam Ho-him was responsible for collecting views from the stakeholders, analysing the data, and promoting their initiative. Despite talking to several stakeholders, the 16-year-old admitted feeling nervous when presenting his team’s ideas at the iGEM competition.
“I was worried that I might not be able to answer the audience’s questions. But it worked out,” the 16-year-old said.