4.4.5 Hemolysis test
The porcine red blood cells separated from the whole blood were gently wash with 3 volumes of saline, then centrifuged at 500~1000 r/min for 5 minutes, repeating the process 2~3 times. After being diluted 20 times, the red blood cells were incubated with an equal volume of saline, deionized water, AIE EVs solution or hydrogels immersed solutions at 37 ℃ for 3h. The supernatants were obtained by centrifugating the mixture at 750g for 5min, and their absorbance at 545 nm will be measured. The hemolysis rates are calculated as the following formula: Hemolysis rate (%) = (A-Asaline) / (Awater - Asaline) ×100%. The hemolysis rate exceeds 5% is considered hemolysis.