Adapted MS/MS Shotgun Lipidomics Approach for Analysis of Cardiolipin Molecular Species.

Cardiolipin (Ptd Gro) is a complex, doubly charged phospholipid located in the inner mitochondrial membrane where it plays an essential role in regulating bioenergetics. Abnormalities in Ptd Gro content or composition have been associated with mitochondrial dysfunction in a variety of disease states. Here, we report the development of an adapted high-resolution data-independent acquisition (DIA) MS/MS shotgun lipidomic method to enhance the accuracy and reproducibility of Ptd Gro molecular species quantitation from biological samples. Utilizing the doubly charged molecular ions and the isotopic pattern with negative mode electrospray ionization mass spectrometry (ESI-MS) using an adapted MS/MS approach, we profiled more than 150 individual Ptd Gro species, including monolysocardiolipin (MLPtd Gro). The method described in this study demonstrated high reproducibility, sensitivity, and throughput with a wide dynamic range. This high-resolution MS/MS shotgun lipidomics approach could be extended to screening aberrations of Ptd Gro metabolism involved in mitochondrial dysfunction in various pathological conditions and diseases.