Simultaneous sample dispensing enhances control in combinatorial screening

High-throughput, combinatorial experiments, which screen a large number of samples at once, have contributed to discoveries in drug development, biology, food science, and other fields. But the methods typically used to create samples for these studies rely on manual preparation or serial-dispensing liquid handlers, which are time-intensive and costly.

While the speed of microfluidic gradient generators makes them a promising alternative, existing systems analyze results on the device itself, disrupting the usual workflow of high-throughput, combinatorial experiments. To address this challenge, Wongwiset et al. introduced the parallel combinatorial microfluidic (PCM) system, which simultaneously generates predetermined combinatorial concentrations for high-throughput screening. The system is cost-effective, rapid, scalable, and compatible with existing laboratory tools and workflows.

Existing liquid handling technologies, such as robotic pipettors, serially dispense samples. In contrast, the superhydrophobic nozzles of the PCM system achieve contactless, synchronous dispensing, eliminating temporal variability in experimental analyses. The system completes any sample set, regardless of size, within five minutes.

“This work presents an alternative approach to conventional liquid handling by providing fast processing time and reliable concentrations,” said author Niphattha Wongwiset.

The authors validated the design with multiple device configurations and confirmed the system’s biocompatibility with an antibiotic cell assay study. The system could be applied to combinatorial, high-throughput applications in various fields, including drug discovery, toxicology, and time-sensitive assays.

“We envision the PCM system becoming an accessible, user-friendly platform that provides reliable, cost-effective combinatorial screening for laboratories of all sizes,” Wongwiset said. “We also believe PCM design principle could be adapted for gas-phase systems, enabling high-throughput combinatorial studies in gaseous toxicology and air pollution research where screening capabilities are limited.”

Source: “Parallelized contactless microfluidic dispenser with superhydrophobic nozzles for scalable combinatorial screening,” by Niphattha Wongwiset, Morgan L. Stephens, Blanca I. Quiñones-Díaz, Aryan Mehboudi, Lydia M. Contreras, and S. V. Sreenivasan, Biomicrofluidics (2026). The article can be accessed at https://doi.org/10.1063/5.0321277 .