Editing Fluorescence microscope (section)

===Biological fluorescent stains===
Many fluorescent stains have been designed for a range of biological molecules. Some of these are small molecules which are intrinsically fluorescent and bind a biological molecule of interest. Major examples of these are [[nucleic acid]] stains such as [[DAPI]] and [[Hoechst stain|Hoechst]] (excited by UV wavelength light) and DRAQ5 and DRAQ7 (optimally excited by red light) which all bind the minor groove of [[DNA]], thus labeling the [[nucleus (cell)|nuclei]] of cells. Others are drugs, toxins, or peptides which bind specific cellular structures and have been derivatised with a fluorescent reporter. A major example of this class of fluorescent stain is [[phalloidin]], which is used to stain [[actin]] fibers in [[mammal]]ian cells. A new peptide, known as the [[Collagen Hybridizing Peptide]], can also be conjugated with [[fluorophore]]s and used to stain ''denatured'' collagen fibers. Staining of the plant [[cell wall]]s is performed using stains or dyes that bind [[cellulose]] or [[pectin]]. The quest for fluorescent probes with a high specificity that also allow live imaging of plant cells is ongoing.<ref name="Bidhendi-2020">{{cite journal|last1=Bidhendi|first1=AJ|last2=Chebli|first2=Y|last3=Geitmann|first3=A|title=Fluorescence Visualization of Cellulose and Pectin in the Primary Plant Cell Wall|journal=Journal of Microscopy|volume=278 |issue=3 |pages=164–181|date=May 2020|doi=10.1111/jmi.12895|pmid=32270489|s2cid=215619998}}</ref>

There are many fluorescent molecules called [[fluorophore]]s or [[fluorochrome]]s such as [[fluorescein]], [[Alexa Fluors]], or [[DyLight Fluor|DyLight 488]], which can be chemically linked to a different molecule which binds the target of interest within the sample.