UV is not selective and a very poor choice for phospholipids (*just look at their structure to understand why). ELSD, CAD and MS are preferred, but also require far more practical experience (many years) and knowledge to use properly (to acquire valid data) too.
HPLC-UV or any UV analysis alone and without derivatization will not work well as phospholipids (or lipids in general) don't have good chromophores. Midsize and large intact liposomes, however, will give UV response which is actually a result of very high scattering that interferes with UV detection, not a true UV absorbance.
In the pharmaceutical industry we use mostly HPLC-CAD (charged aerosol detector) with C8 or C18 column. Prior to injecting them, you may have to do extraction of the lipids you want with different solvents (DCM, methanol, etc, or mixture of solvents). It's a procedure that's sensitive enough and can resolve multiple lipids on the same run.
I have also successfully used HPLC-RID (refractive index) for simple mixtures. RID cannot be used with gradient, so you lose the ability to resolve mixtures; the detector also has poor sensitivity. HPLC couple with conductivity detector is something that works well too.
If you are in a big need for a method but don't have the budget, try looking into TLC. I have used it many times for single phospholipids and mixtures of two phospholipids. A 2D TLC can resolve mixtures. This is widely used method so if you search it online you will find procedures, sprays, and recommended eluents that can be used.
Thank You so much for your advice @Petroslav Chipinski and @William Letter
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