Multifunctional Single-Layered Graphene Quantum Dots Used for Diagnosis of Mitochondrial Malfunction-Related Diseases

Mitochondria are critical organelles in eukaryotes that efficiently generate adenosine 5'-triphosphate (ATP) for various biological activities, and any defect in the process of ATP synthesis may lead to mitochondrial dysfunction and directly link to a variety of medical disorders. Monitoring the ATP variations in cells is key for innovative early diagnosis of mitochondrial diseases. Herein, multifunctional single-layered graphene quantum dots (s-GQDs) with bright green emission were constructed, which exhibit strong binding affinity for ATP and good mitochondria targeting ability. Using the proposed s-GQDs, we successfully discriminated the primary smooth muscle cells isolated from the transgenic mouse (heterozygote sarco/endoplasmic reticulum Ca²⁺ ATPase (SERCA) 2 C674S knock-in mouse) with mitochondrial disorders or their littermate controls, indicating s-GQDs as promising probes for the study of cell metabolism and mitochondrial malfunction-related diseases, and targeting endoplasmic reticulum stress is an effective way to modulate metabolic pathways relevant to SERCA 2 inactivity mitochondrial dysfunction.