Porphyrin–peptide conjugates in biomedical applications

Abstract

The conjugation of peptides to porphyrins and related tetrapyrrole based macrocycles have extended their applications in biological systems, where the photophysical properties of these molecules and their ability to coordinate metals can be exploited for detecting and opposing to the onset of important diseases. This review presents a survey of the published literature over last years on biomedical applications of these hybrid compounds, mostly in the field of photodynamic therapy (PDT), but also in sensing key metabolites and peculiar structures of biomolecules in living systems. Peptides based strategies to improve the efficacy of the photosensitizer (PS) in PDT will be discussed, as well as solutions to overcome some limitations recently emerged in the use of peptides as delivery vehicles. An overview on possible application of porphyrin–peptide conjugates in detection of biomarkers of physiological and pathological states will be also presented.

Penetrating the Blood-Brain Barrier with New Peptide–Porphyrin Conjugates Having anti-HIV Activity

“…Conjugation between porphyrins and peptides has received considerable attention in the past decade due to the enhanced properties of the newly generated species, including the ability to overcome some of the obstacles related to porphyrin application. ,,, For example, peptide conjugation can improve poor water solubility of some porphyrins, reduce their aggregation tendency, and/or enhance porphyrin biological efficacy thanks to higher cell uptake of the conjugate vs the single porphyrin molecule. ,, In parallel with the broader biological applications of PPCs, the need for optimized approaches allowing quantitative conjugation at various sites has increased. So far, several strategies using a variety of chemistries have been adopted, neither giving clear advantages over others .…”

“…We hypothesized that, by conjugating a porphyrin antiviral to a trans-BBB peptide shuttle, one might circumvent the challenges to fighting viral CNS diseases, in particular, HAND. Methods for peptide–porphyrin conjugation, both in solution and in solid phase, have been described, − with a growing consensus that, in terms of simplicity and expediency, on-resin conjugation offers palpable advantages over solution procedures. However, comparative studies showing how a given strategy (e.g., solution vs on-resin, coupling chemistries, etc.)…”

Cell‐Penetrating Peptide‐Conjugated BF2‐Oxasmaragdyrins as NIRF Imaging and Photothermal Agents

“…Similarly, Matsushita and co‐workers have shown that the polyarginine (R 9 ) sequence a cell‐penetrating peptide targets human glioblastoma cell lines . Furthermore porphyrin–peptide conjugates have been used in various biomedical applications such as PDT by generating ROS …”

Photodynamic Antimicrobial Chemotherapy: Advancements in Porphyrin-Based Photosensitize Development

“…Porphyrins and other tetrapyrrole molecules such as phthalocyanines and chlorins possess many desirable properties for use as photosensitizers in PACT. Key among these is their ability to absorb strongly in the UV-Vis near the IR region of the electromagnetic spectrum and their ability to generate a considerable triplet quantum yield, which makes them remarkable generators of ROS ( Biscaglia and Gobbo, 2018 ; Nam et al, 2000 ) as shown in Figure 1 . As a result, porphyrins have been found to have remarkable potential as antimicrobial agents ( Vzorov et al, 2002 ).…”