pH-Responsive ZIF-8@Polydopamine Nanocarrier for Co-Delivery of Letrozole and Cisplatin in Breast Cancer Therapy

A ZIF-8/polydopamine (PDA) nanocarrier was prepared for co-delivery of letrozole and cisplatin and evaluated by FTIR, SEM, TGA, XRD, buffer-release testing, and MCF-7 viability assays. The supplied release curves show enhanced release in acidic medium (pH 5.5) relative to the nominally neutral condition, with approximately 67% of letrozole and 85% of cisplatin released by 48 h in acidic medium. The neutral-buffer pH and some plotted release values require verification against experimental records. According to Table 1, the ZLDC IC₅₀ values were 617.42 µg/mL after 24 h and 26.08 µg/mL after 48 h. However, the reported combination-index calculation and kinetic-fit parameters are not fully reconcilable with the available supporting figures. The findings provide preliminary evidence for pH-associated release and in vitro anticancer activity, while further data verification is needed before mechanistic, synergy, or in vivo safety claims can be established.