The University of California, Santa Cruz team has made significant progress in chip based sensing devices for detecting or analyzing substances, laying the foundation for the development of highly sensitive portable integrated optical fluid sensing devices. These devices can still perform multiple types of medical tests simultaneously, even when involving biological particles with significant concentration changes and completely different types. The research findings were published in the latest issue of the journal Optics.
Researchers have applied new signal processing technology to biosensors based on optofluid chips, which can seamlessly detect nano bead mixtures of 8 orders of magnitude, expanding the working concentration range of the sensor by more than 10000 times.
The team said that the new device is sensitive enough to not only detect a single biomolecule, but also work in a very wide concentration range to simultaneously measure and distinguish multiple particle types.
This multi type analysis and testing platform is based on a microfluidic chip, which detects particles by irradiating them with a laser beam and then measuring their response with a photosensitive detector.
It also enables the platform to have the sensitivity required to perform various types of analyses, including detecting particles such as nucleic acids, proteins, viruses, bacteria, and cancer biomarkers. In this new work, researchers have also developed a signal processing method that can simultaneously detect high and low concentration particles. They combine different signal modulation frequencies: high-frequency laser modulation to distinguish individual particles with low concentrations, and low-frequency laser modulation to simultaneously detect large signals from many particles at high concentrations. The team also applied a recently developed fast algorithm for real-time recognition and high-precision differentiation.
This signal analysis method essentially uses nanoscale bead solutions of different concentrations and fluorescence colors to pump optofluid biosensor chips. At present, it can correctly identify nanoparticles with concentration differences exceeding 10000 times in the mixture. In the future, it will be used to analyze the molecular products from artificial neuron cell tissue Organoid, bringing new insights into neurogenic diseases, pediatric cancer and other fields.