Nile red is a common lipid dye. Nile red is a hydrophobic and metachromatic dye with poor solubility and fluorescence in water, with colour emission varying from deep red to strong yellow gold in hydrophobic environments [1].
Nile red can dye the cholesterol in the human plasma through staining of lipid vesicles in smooth muscle cells and in cultured macrophages incubated at low density, using the excitation/emission wavelengths 450 to 500/>528 [2]. Nile red was also used to study membrane heterogeneity [3] and ligand-hydrophobic protein surface interactions with the alternative wavelengths 570/610 [4] and to study enzyme mechanism by using the wavelengths 550/640 to 660 [5]. Nile red has also been successfully used to stain intracellular neutral lipids that is, TAG and cholesterol esters in yeast, fungi with coupled wavelengths 488/565 to 585 [6] and also in microalgae, with wavelengths set to 488 to 525/570 to 600 [7] or to stain total lipids with wavelengths set to 490/585 [8].
References:
[1]. Rumin J, Bonnefond H, Saint-Jean B, et al. The use of fluorescent Nile red and BODIPY for lipid measurement in microalgae[J]. Biotechnology for biofuels, 2015, 8(1): 1-16.
[2]. Greenspan P, Mayer E P, Fowler S D. Nile red: a selective fluorescent stain for intracellular lipid droplets[J]. The Journal of cell biology, 1985, 100(3): 965-973.
[3]. Ira and, Krishnamoorthy G. Probing the link between proton transport and water content in lipid membranes[J]. The Journal of Physical Chemistry B, 2001, 105(7): 1484-1488.
[4]. Sackett D L, Wolff J. Nile red as a polarity-sensitive fluorescent probe of hydrophobic protein surfaces[J]. Analytical biochemistry, 1987, 167(2): 228-234.
[5]. Ruvinov S B, Yang X J, Parris K D, et al. Ligand-mediated Changes in the Tryptophan Synthase Indole Tunnel Probed by Nile Red Fluorescence with Wild Type, Mutant, and Chemically Modified Enzymes (∗)[J]. Journal of Biological Chemistry, 1995, 270(11): 6357-6369.
[6]. Kimura K, Yamaoka M, Kamisaka Y. Rapid estimation of lipids in oleaginous fungi and yeasts using Nile red fluorescence[J]. Journal of microbiological methods, 2004, 56(3): 331-338.
[7]. Cooksey K E, Guckert J B, Williams S A, et al. Fluorometric determination of the neutral lipid content of microalgal cells using Nile Red[J]. Journal of microbiological methods, 1987, 6(6): 333-345.
[8]. Lee S J, Yoon B D, Oh H M. Rapid method for the determination of lipid from the green alga Botryococcus braunii[J]. Biotechnology techniques, 1998, 12(7): 553-556.
尼罗红是一种常见的脂质染料。尼罗红是一种疏水性异染性染料,在水中溶解度差且发荧光,在疏水环境中发射的颜色从深红色到强黄色不等[1]。
使用激发/发射波长 450 至 500/>528,尼罗红可以通过染色平滑肌细胞和培养的低密度巨噬细胞中的脂质囊泡来染色人血浆中的胆固醇 [2] 。尼罗红还用于研究膜异质性 [3] 和配体疏水蛋白表面与替代波长 570/610 [4] 的相互作用,并通过使用研究酶机制波长 550/640 至 660 [5]。尼罗红也已成功用于染色细胞内中性脂质,即酵母中的 TAG 和胆固醇酯,耦合波长为 488/565 至 585 的真菌 [6] 以及微藻,波长设置为488 至 525/570 至 600 [7] 或将波长设置为 490/585 [8] 对总脂质进行染色。