Table I. Free fatty acids, cholesterol and cholesteryl esters are found in normal human nasal fluid in μg/ml concentrations.
Nasal fluid collected from individual donors (D) and pooled nasal fluid were supplemented with an internal standard (heptadecanoic acid, a plant fatty acid absent in humans) and lipid extracts were subjected to rpHPLC/ELSD. Native lipids were identified and quantified according to established reference chromatograms and standard curves and recovery of the internal standard. Only lipids which have been confirmed by a second technique are included here, concentrations are in μg/ml.
| Fatty acids1 | Cholesterol2 | Cholesteryl esters3 | ||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Individual Nasal Fluids | Myristic4 (14:0) | Palmitic5 (16:0) | Palmitoleic4 (16:1) | Stearic (18:0) | Oleic5 (18:1) | Linoleic4 (18:2) | -palmitate | -linoleate | -arachidonate | |
| D1 | 4.8 | 10.1 | 5.8 | 8.0 | 0.3 | 0.2 | 27.8 | 11.4 | 17.9 | 8.6 |
| D2 | 19.0 | 56.3 | 27.2 | 0.0 | 6.9 | 12.0 | 71.4 | 79.8 | 86.0 | 69.9 |
| D3 | 1.3 | 3.4 | 1.8 | 0.0 | 0.0 | 0.1 | 6.4 | 4.9 | 4.7 | 4.2 |
| D5 | 6.9 | 21.2 | 9.4 | 0.0 | 0.1 | 0.1 | 90.3 | 25.2 | 41.6 | 21.1 |
| D6 | 2.7 | 6.0 | 3.5 | 6.6 | 0.1 | 0.1 | 11.2 | 7.2 | 15.6 | 7.1 |
| D8 | 23.7 | 7.6 | 26.0 | 7.6 | 0.0 | 13.9 | 14.23 | 7.36 | 13.15 | 8.04 |
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| Mean | 9.7 | 17.4 | 12.3 | 3.7 | 1.2 | 4.4 | 36.9 | 22.7 | 29.8 | 19.8 |
| SEM | 3.8 | 8.2 | 4.7 | 1.7 | 1.1 | 2.7 | 14.4 | 11.8 | 12.3 | 10.3 |
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| Pooled Nasal Fluid | ||||||||||
| D1,D2,D3,D7 | 10.9 | 13.1 | 12.8 | 13.7 | 0.2 | 0.2 | 17.8 | 15.7 | 28.7 | 13.3 |
Confirmed by GC/MS;
Confirmed by enzymatic assay;
Confirmed by MS/MS;
4 and 5 Co-elute in rpHPLC at 4.6 – 5 min and at 5.8 – 6.0 min, respectively. Based on GC/MS intensity distribution in nasal fluid from donors D1, D2, D3, and D6 (see Figure 1 c) myristic acid, palmitoleic and linoleic acid are assigned 10%, 45% and 45% of the peak area, respectively, and palmitic and oleic acid are each assigned 50% of the peak area.