Optical trapping of microalgae at 735-1064Â nm: Photodamage assessment

► Living microalgal cells were trapped in optical tweezers using laser wavelengths 735-1064 nm. ► Photodamage was assessed by pulse amplitude modulation chlorophyll fluorescence microspectroscopy. ► Loss of fluorescence in Trachydiscus minutus was observed up to 885 nm trapping laser wavelength. ► Wavelengths over 935 nm caused no observable fluorescence loss, suggesting minimal photodamage.