This tiny, voice-activated device could extract and pre-process bacterial DNA, making laboratories safer for scientists and engineers. Credit: Adapted from ACS Sensors 2023, DOI: 10.1021/acssensors.2c01849
Yelling out commands to Siri or Alexa is part of everyday life for many people today. But “Alexa, play my favorite music” and “Alexa, pretreat my pathogenic bacteria sample” are a little different.
Still, researchers at Kyung Hee University in South Korea are working to make the latter command more common in the near future.
In a new study published in ACS sensorresearchers describe the development of a portable sample pretreatment microsystem for bacterial samples that can be automatically operated by voice recognition via a smartphone app.
The research team first created a microfluidic chip with multiple chambers linked together by six three-way solenoid valves operated by a microcontroller connected to a Bluetooth module. We then used our existing speech recognition software to customize the smartphone app to listen for specific voice commands.
When the user says one of the operational commands, the app wirelessly sends a start signal to the microcontroller. After receiving the signal, the microcontroller automatically initiates a series of steps. In testing, the microsystem successfully performed sample loading, washing, and release of purified DNA into the collection chamber.
Studies have shown that voice-controlled devices successfully extract DNA. Salmonella typhimuriumPurifies 10 µL of sample in less than 1 minute with 70% efficiency.
When the team evaluated system performance against commercially available QIAGEN kits, they found that the microsystems did not perform as well. However, it had distinct advantages of voice control, portability, and rapid automation. Additionally, the palm-sized device weighs only 11 ounces and can be powered by a portable he battery or smartphone charger, making it particularly suitable for use in resource-poor countries or required on-site testing locations. .
For example, during the COVID-19 pandemic, many patient samples were taken and collected at diagnostic centers. Samples had to be tested in a laboratory by trained technicians, but in the early days of the pandemic many unresolved issues, such as the contagiousness of SARS-CoV-2 and the lack of personal protective equipment (PPE). There were resolution problems and obstacles.
Even when gloves became more readily available, technicians still had to handle viral samples and touch equipment such as centrifuges for RNA extraction and thermal cyclers for gene amplification. These actions alone carry the potential for machine-to-human or human-to-human contamination.
A pretreatment microfluidic system that works with voice recognition almost completely eliminates the risk of contamination. This is even higher for more dangerous diseases such as Ebola and cholera.
In April 2022, the Democratic Republic of the Congo recorded its sixth Ebola outbreak in just four years. It then hit neighboring Uganda, killing more than 55 people. Moreover, cholera hit Haiti hard last year, but it wasn’t the only country affected. According to the World Health Organization, cholera will be detected in about 30 countries in 2022, but less than 20 countries have reported infections in the last five years.
Miniaturized devices that require only a portable battery or smartphone charger will make a difference in resource-poor regions like Uganda and Haiti.
Researchers say voice recognition systems could also help scientists with disabilities take tests more easily.
