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

: Cardiolipin (Ptd2 Gro) is a complex, doubly charged phospholipid located in the inner mitochondrial membrane where it plays an essential role in regulating bioenergetics. Abnormalities in Ptd2 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/MSALL shotgun lipidomic method to enhance the accuracy and reproducibility of Ptd2 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/MSALL approach, we profiled more than 150 individual Ptd2 Gro species, including monolysocardiolipin (MLPtd2 Gro). The method described in this study demonstrated high reproducibility, sensitivity, and throughput with a wide dynamic range. This high-resolution MS/MSALL shotgun lipidomics approach could be extended to screening aberrations of Ptd2 Gro metabolism involved in mitochondrial dysfunction in various pathological conditions and diseases.