11. To force this alternative emission to occur, an incident photon must strike the fluorophore . 12. Unfortunately, this high intensity laser can lead to the issue of photobleaching the fluorophore . 13. Optical fluorescent DO sensors use a light source, a fluorophore and an optical detector. 14. The fluorophore is immersed in the sample. 15. One particularly powerful method is the combination of antibodies coupled to a fluorophore as in immunostaining. 16. Another inner filter effect occurs because of high concentrations of absorbing molecules, including the fluorophore . 17. The resulting pMHC-streptavidin-fluorophore tetramer can be added to a sample of cells. 18. A reaction of phthalic anhydride with resorcinol in the presence of zinc chloride gives the fluorophore Fluorescein. 19. When these two parts meet, they form a fluorophore on a timescale of minutes or hours. 20. Similarly, a fluorophore can be attached instead for fluorescent labelling, or an antigen for immunodetection.
