Nile red staining

Gorenflo V, Steinbiichel A, Marose S, Rieseberg M, Scheper T (1999) Quantification of bacterial polyhydroxyalkanoic acids by Nile red staining. Appl Microbiol Biotechnol 51 765-772... 

Satpati, G. G., and R. Pal. 2014. Rapid Detection of Neutral Lipid in Green Microalgae by Flow Cytometry in Combination with Nile Red Staining—An Improved Technique. Annals of Microbiology l-13. 

Stain and polarity indicator. Nile red stains intracellular lipid red. Will not fluoresce in most polar solvents, however when in a lipid-rich environment can be intensely fluorescent, with colours varying from a deep red to strong yellow-gold emission [126]. 

Zeiser [reported in 187] modified the conditions of the gas-chromatographic detection of poly(3-hydroxyalkanoates) developed in 1978 [181] to adapt the method for the determination of P(3HB-cc -4HB). Measurement of PHB in live cells of R. eutropha by flow cytometry and spectrofluorometry after Nile-Red staining of granules has been recently investigated [188]. The authors noted that the rapidity of the methods could be useful for process control during cultivation. 

Greenspan P, Mayer EP, Fowler SD. Nile red A selective fluorescent stain for intracellular lipid droplets, J Cell Biol 1985 100 965-73. 

Daban JR, Bartolome S, Bermudez A, Alba FJ. Rapid and sensitive staining of unfixed proteins in polyacrylamide gels with Nile red. in Walker JM. ed. The Protein Protocols Handbook. Totowa Humana Press, 2002 243-9. 

Xia, Z., E-L. Appelkvist, J. W. Depierre, and L. Nassberger. 1997. Tricyclic antidepressant-induced lipidosis in human monocytes in vitro as well as monocyte derived cell line, as monitored by spectrofluorimetry and flow cytometry after staining with Nile red. Biochemical Pharmacology 53 1521-1532. 

Figure I. Fluorescence microscopy of SinorUzobium meliloti stained widi Nile red. (left) free-living cells containing multiple yellow-fluorescent intracellular inclusions of poly-P-hydroxybutyrate (right) bacteroid cells extracted from nodules of Medicago saliva with no granules.

Therefore, a viable-colony staining method has been developed which involves the direct inclusion of the lipophilic dyes Nile red or Nile blue A in the agar medium. This method requires a very low dye concentration, does not affect cell growth and obviates the need to produce master plates. However, the viable-colony method is more applicable for screening Gram-negative bacteria than Gram-positive bacteria [8]. Moreover, this method has its own drawbacks such as the requirement for appropriate carbon sources for the cultivation... 

The method for the rapid quantification of PHA was achieved not only by introducing the fluorescence Nile red or NBA stains as previously discussed, but by also using infrared spectroscopy. Similar to the dye staining method, infrared spectroscopy avoids the use of solvents, and requires minimal sample volume and preparation... 

Kirschner, M. and Hara, K. (1980) A new method of local vital staining of amphibian embryos using ficoU and crystals of Nile Red. Mikroskopie 36,12-15. 

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