[Establishment and application of a knowledge-directed pseudo-targeted analytical method for diabetic retinopathy].

Diabetic retinopathy （DR） is a common blinding eye disease caused by diabetes mellitus and is the leading cause of acquired vision loss in adults worldwide. DR is asymptomatic in its early stages， and patients often miss the optimal treatment window by the time they seek medical attention due to vision impairment. Traditional methods used for DR diagnosis have inherent limitations and are not conducive to large-scale rapid screening. Biomarkers can reflect the stage of the disease owing to their specificity and sensitivity， which is crucial for the early diagnosis of DR. In the present study， 142 potential literature-based biomarkers associated with DR were included in a knowledge-directed strategy. And metabolites with different physicochemical properties were chromatographically separated using a 100-mm Discovery HS F5 column. A pseudo-targeted metabolomics method based on ultra-high performance liquid chromatography-tandem mass spectrometry （UHPLC-MS/MS） that simultaneously scans positive and negative ions was established to improve analysis coverage and throughput. The method was validated using eight representative isotope-labeled internal standards as analytical targets. All isotope-labeled internal standards exhibited satisfactory linearities in both positive- and negative-ionization modes， with linear dynamic ranges spanning over three orders of magnitude and correlation coefficients （