Coenzyme Q10 (CoQ10) is an important cofactor in the mitochondrial respiratory chain and a potent endogenous antioxidant. CoQ10 deficiency is often associated with numerous diseases, and patients can benefit from CoQ10 supplementation, being more effective when diagnosed and treated early. Due to the increased interest in CoQ10 deficiency, several methods for CoQ10 analysis from plasmatic, muscular, fibroblast, and platelet matrices have been developed. These sampling techniques are not only highly invasive but also too traumatic for periodic clinical monitoring. In the present work, we describe the development and validation of a novel non-invasive sampling method for quantification of CoQ10 in buccal mucosa cells (BMCs) by microHPLC. This method is suitable for using in a routine laboratory and useful for sampling patients in pediatry. CoQ10 correlation was demonstrated between BMCs and plasma levels (Spearman r, 0.4540; p < 0.001). The proposed method is amenable to be applied in the post treatment monitoring, especially in pediatric patients as a non-invasive sample collection. More studies are needed to assess whether this determination could be used for diagnosis and if this matrix could replace the traditional ones.
