1,2-Dipalmitoyl-sn-glycor-3-PG (sodium salt) undergoes C-O, C=O, and - PO2-chemical bond cleavage upon exposure to ultraviolet radiation, leading to a decrease in the stability of the monolayer film; When DNA is present in the subphase, 1,2-Dipalmitoyl-sn-gycero-3-PG (sodium salt) and the ion products generated by DNA degradation can stabilize and complete DPPG molecules, reducing damage caused by UV irradiation.