This high purity fluorescent product is ideal for the identification of dihydroceramide in samples and biological systems. 7- nitrobenzofurazan (NBD) has been shown to have only a small influence on lipid adsorption into cells and cellular membranes. This fluorescent analog of natural dihydroceramide is comparable to C6:0-dyhidroceramide in many biological functions.1,2 Dihydroceramide is a critical intermediate in the synthesis of many complex sphingoid bases. Inhibition of dihydroceramide synthesis by some fungal toxins that have a similar structure causes an increase in dihydroceramide and dihydroceramide-1-phosphate and a decrease in other sphingolipids leading to a number of diseases including oesophageal cancer. Dihydroceramide, synthesized by the acylation of sphinganine, is subsequently converted into ceramide via a desaturase enzyme. N-(4-Hydroxyphenyl) retinamide (4-HPR) has been tested as an anti-cancer agent. It inhibits the dihydroceramide desaturase enzyme in cells resulting in a high concentration of dihydroceramide and dihydro-sphingolipids and this is thought to be the cause of the anti-cancer effects.3 Dihydrosphingosine induces cell death in a number of types of malignant cells.