Chemical Profiling of Washed Platelet Biomaterials

After confirming the higher biocompatibility of wPB compared to ePB, we identified the chemical compositions of wPB in accordance with our previous protocol [31 (link)]. In summary, an LC–MS instrument (Time-of-Flight/6500 series, Agilent, Palo Alto, CA, USA) connected to a high-performance liquid chromatography (HPLC) system (1290 Infinity Binary Pump, Agilent) with an electrospray ionization (ESI) interface was utilized for chemical profiling. Chromatographic separations were carried out using a C18 column (5 µm, 150 mm × 2.1 mm; ZORBAX Eclipse Plus C18, Agilent) at a flow rate of 0.2 mL/min, with two mobile phases. The gradient system consisted of high A for the first 3 min, high B for the next 15 min, and then high A again (A: 0.1% formic acid in water and B: 0.1% formic acid in acetonitrile). The column temperature was maintained at 40 °C, and the injection volume was 3 µL, with a total run time of 30 min. Spectra were obtained in ESI- modes using a photodiode array detector. An Agilent Database Library was used for compound verification.