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• Synthesis of four novel L,L-diphenylalanine (FF) functionalized porphyrins. • Photophysical studies showing that FF conjugation influences porphyrin aggregation. • Post-irradiation with 650 nm light decreased cell viability of a cervical tumor cell line to 70 %, with no cell death induced without light. • Absence of hemolytic activity and non-toxicity to red blood cells at tested concentrations. • Efficient cellular uptake of peptide-porphyrin compounds, demonstrated by flow cytometry after 4 hours of incubation. Photodynamic therapy (PDT) triggers selective cell death through intensive oxidative stress induced by the generation of reactive species by a photosensitizer (PS) excited by light. In this work, we report the synthesis of four novel porphyrins conjugated to the self-assembling dipeptide L,L-diphenylalanine (FF), effectively inhibiting cervical tumor cell growth. The PS were prepared using the classical A 3 B strategy, with functionalized and non-functionalized porphyrins obtained in moderate yields over 3 to 4 steps. Absorption and fluorescence studies indicate that the FF attached to the porphyrin ring influences their aggregation at micromolar concentrations. The compounds were efficiently internalized by HeLa cells after 4 h of incubation. Cytotoxicity tests performed in the 1.25–5.0 µmol L−1 range showed that cell viability was reduced to 70 % after irradiation (650 nm). A correlation between cell permeation and the cell death mechanism promoted by the porphyrin was observed. [Display omitted] [ABSTRACT FROM AUTHOR]