pH‐Responsive Polyethyleneimine‐Coated Biogenically Synthesized Fe ₃ O ₄ Nanoparticles as Potential Vehicles for Targeted Drug Delivery in Cancer Therapy

Abstract The study and development of drug delivery nano systems for cancer treatment are attracting great attention in recent years. In this work, we explore the synthesis and application of Fe 3 O 4 @PEI‐CUR‐NPs, magnetic iron oxide (Fe 3 O 4 ) nanoparticles (NPs) encapsulated in a matrix with polyethyleneimine (PEI) and curcumin (CUR) for targeted drug delivery system. Fe 3 O 4 NPs were synthesized by using on biogenic method utilizing Hylocereus undantus fruit extract and subsequently functionalized with PEI to form Fe 3 O 4 @PEI‐ NPs, further loaded with CUR to obtain Fe 3 O 4 @PEI‐CUR‐NPs. The synthesized Fe 3 O 4 @PEI‐CUR‐NPs exhibited uniform morphology, confirmed by SEM and TEM analyses, with sizes ranging from 20 to 30 nm. EDS spectra confirmed the elemental composition, indicating the presence of carbon, nitrogen, oxygen, chlorine, and iron. Magnetic property analysis revealed saturation magnetization values of 62.3 emu/g for Fe 3 O 4 @PEI‐CUR‐NPs. Thermal stability was demonstrated through TG, indicating a residual mass of approximately 42.5% for Fe 3 O 4 NPs and 11.6% for Fe 3 O 4 @PEI‐CUR‐NPs at 500 °C. Drug encapsulation efficiency was determined to be 89.10% under acidic conditions. In vitro release studies showed pH‐responsive drug release, with rapid release at pH 5.2 attributed to PEI degradation. Moreover, Fe 3 O 4 @PEI‐CUR‐NPs exhibited anti‐inflammatory activity with an IC 50 value of 18.10 µg/mL and significant cytotoxicity against cancer cell lines, with IC 50 values ranging from 85.23 to 193.40 µg/mL. These findings suggest the potential of Fe 3 O 4 @PEI‐CUR‐NPs as a promising platform for targeted drug delivery and cancer therapy, addressing the limitations of conventional chemotherapy.