THP-1 Monocyte Biocompatibility Assay

THP-1 cells (ATCC, Manassas, VA, USA) were cultured in RPMI 1640 medium (Thermo Fisher Scientific), supplemented with 10% fetal bovine serum (FBS; Quality Biological) and 0.05 mM 2-mercaptoethanol (VWR), at 37 °C under 5% CO₂ for 2 weeks. The media was refreshed every 2–3 days to maintain a cell density of 0.2–1.0×10⁶ cells/ml.^{63 (link)} The biocompatibility of the AIS/Zn QDs was assessed by incubating THP-1 monocytes (ca. 10⁵ cells/mL) in PBS buffer at 37 °C in the absence (PBS buffer only) and presence of 25 μM and 50 μM AIS/Zn QDs. Following 1 h and 24 h incubation, a Trypan blue dye exclusion assay was employed to stain dead cells, and cell viability was quantified with an Invitrogen Countess II Automated Cell Counter.