Micro patterned quantum dots excitation and imaging for cellular microarray screening

•We describe a quantum dot (QD)-based thin-film multicolor light source array for lab-on-a-chip cellular array imaging.•Microwell array and the multicolor light sources are created based on printing technologies.•Use of QDs allowed simple multicolor excitation system that covers the wide spectrum of visible wavelengths.•We have performed transmission mode imaging of cancer cell morphology to evaluate the nucleus–cytoplasm ratios.•We have also performed immunofluorescence imaging of cancer cells cultured in a microwell array.

We developed a colloidal quantum dot (QD)-based multicolor excitation light source array designed for compact lab-on-a-chip cell screening and imaging. We have demonstrated multicolor ex vivo transmission mode microscopy to evaluate the nucleus–cytoplasm ratios of cancer cells. We have also performed immunofluorescence excitation of two types of cancer cells (MDA-MB 435 and SKBR3) that are cultured in a microwell array to quantify the disease specific protein expression. Printed array of color filters and microwells were used to perform fluorescence excitation and measurement of the biomarkers. Our method provides patterned multicolor light sources at low-cost that are suitable for high-throughput microarray cellular screening.