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

Cardiolipin (Ptd₂Gro) is a complex, doubly charged phospholipid located in the inner mitochondrial membrane where it plays an essential role in regulating bioenergetics. Abnormalities in Ptd₂Gro 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^ALL shotgun lipidomic method to enhance the accuracy and reproducibility of Ptd₂Gro 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^ALL approach, we profiled more than 150 individual Ptd₂Gro species, including monolysocardiolipin (MLPtd₂Gro). The method described in this study demonstrated high reproducibility, sensitivity, and throughput with a wide dynamic range. This high‐resolution MS/MS^ALL shotgun lipidomics approach could be extended to screening aberrations of Ptd₂Gro metabolism involved in mitochondrial dysfunction in various pathological conditions and diseases.