Science Magazine | AAAS: Science Translational Medicine Follow Serotonin measurement by lab-on-a–contact lens in porcine and human tears | Science Translational Medicine A reversible lab-on-a–contact lens quantifies tear serotonin, revealing a noninvasive biomarker of stress across mice, pigs, and humans. https://www.science.org/doi/10.1126/scitranslmed.adv9538 science.org