Measurement of singlet oxygen generation of 9(Hydroxymethyl)anthracene substituted silicon phthalocyanine by sono-photochemical and photochemical studies

Exploring improved strategies for therapeutic studies and biological activities of novel zinc and indium phthalocyanines

This study investigates novel zinc and indium phthalocyanines with Schiff base and sulphur moieties, focusing on their potential for cancer therapy and antimicrobial applications. It explores the effectiveness of photochemical and sono-photochemical methods to enhance singlet oxygen production, which is crucial for photodynamic therapy. The synthesized complexes in this study demonstrated high singlet oxygen quantum yields, with D3 (ZnPc) and D4 (InPc) showing ΦΔPDT values of 0.71 and 0.75, and ΦΔSPDT values of 0.91 and 0.94, respectively. Furthermore, the evaluation for biological properties revealed that both D3 and D4 exhibit significant antidiabetic properties, DPPH radical scavenging activity, DNA cleavage, antimicrobial activity, biofilm inhibition, and microbial cell viability impacts, both with and without photodynamic therapy. Notably, D3 and D4 achieved antimicrobial cell viability inhibition rates of 84.67 ± 4.67% and 98.32 ± 5.96%, respectively, showcasing their effectiveness in photodynamic antimicrobial therapy. Overall, the study highlights the potential of these phthalocyanine complexes as advanced photosensitizers, with strong singlet oxygen generation and promising biological activities, paving the way for future therapeutic applications.

Monitoring of singlet oxygen generation of a novel Schiff-base substituted silicon phthalocyanines by sono-photochemical studies and in vitro activities on prostate cancer cell

This study demonstrates the potential of sono-photodynamic therapy as an effective approach for enhancing singlet oxygen generation using the synthesized Schiff-base diaxially substituted silicon phthalocyanines. In photochemical studies, the singlet oxygen quantum yields (Φ∆) were determined as 0.43 for Si1a, 0.94 for Q-Si1a, 0.58 for S-Si1a, and 0.49 for B-Sia1. In sono-photochemical studies, the Φ∆ values were reached to 0.67 for Si1a, 1.06 for Q-Si1a, 0.65 for S-Si1a, and 0.67 for B-Sia1. In addition, this study demonstrates the therapeutic efficacy of phthalocyanines synthesized as sensitizers on the PC3 prostate cancer cell line through in vitro experiments. The application of these treatment modalities exhibited notable outcomes, leading to a substantial decrease in cell viability within the PC3 prostate cancer cell line. These findings highlight the potential of utilizing these synthesized phthalocyanines as promising therapeutic agents for prostate cancer treatment.

Design consideration of phthalocyanines as sensitizers for enhanced sono-photodynamic combinatorial therapy of cancer

Cancer remains one of the diseases with the highest incidence and mortality globally. Conventional treatment modalities have demonstrated threatening drawbacks including invasiveness, non-controllability, and development of resistance for some, including chemotherapy, radiation, and surgery. Sono-photodynamic combinatorial therapy (SPDT) has been developed as an alternative treatment modality which offers a non-invasive and controllable therapeutic approach. SPDT combines the mechanism of action of sonodynamic therapy (SDT), which uses ultrasound, and photodynamic therapy (PDT), which uses light, to activate a sensitizer and initiate cancer eradication. The use of phthalocyanines (Pcs) as sensitizers for SPDT is gaining interest owing to their ability to induce intracellular oxidative stress and initiate toxicity under SDT and PDT. This review discusses some of the structural prerequisites of Pcs which may influence their overall SPDT activities in cancer therapy.

Comparing Singlet Oxygen Generation of Schiff Base Substituted Novel Silicon Phthalocyanines by Sonophotochemical and Photochemical Applications

Although the sonophotodynamic method has an effective therapeutic outcome for anticancer treatment compared with the photodynamic method, there are not enough related studies in the literature and this study aims to contribute to the development of sonophotodynamic studies. For this purpose, the Schiff base substituted silicon phthalocyanines were designed and synthesized as effective sensitizer candidates and the photophysicochemical and sonophotochemical features of the phthalocyanines were examined to increase singlet oxygen efficiency. The calculated ΦΔ values indicate that the contribution of substituent groups improved the production of singlet oxygen compared with silicon (IV) phthalocyanine dichloride (SiPcCI2 ) and also the sonophotochemical applications increased the singlet oxygen yields. The ΦΔ values (ΦΔ  = 0.76 for axially bis-{4-[(E)-(pyridin-3-ylimino)methyl]phenol} substituted silicon (IV) phthalocyanine (2a), 0.68 for axially bis-4-[(E)-{[(pyridin-3-yl)methyl]imino}methyl]phenol substituted silicon (IV) phthalocyanine (2b) in photochemical study) reached to ΦΔ  = 0.98 for 2a, 0.94 for 2b in sonophotochemical study. This article will enrich the literature on increasing singlet oxygen yield.

Synthesis of axially Schiff base new substituted silicon phthalocyanines and investigation of photochemical and sono-photochemical properties

Sono-photodynamic therapy, which show a very high therapeutic effect compared to photodynamic therapy, is a newer method for anticancer treatments. However, unlike Photodynamic therapy (PDT), the number of studies measuring the efficiency of singlet oxygen for the Sono-photodynamic therapy (SPDT) method is quite insufficient in the literature. Therefore, this study aimed to synthesis novel axially substituted silicon (IV) phthalocyanines containing imine groups with improved photochemical properties and then reported the efficiency of singlet oxygen by both of photochemical and sono-photochemical studies. According to the results, the substituent group increased the singlet oxygen yield of silicon (IV) phthalocyanine dichloride and the sono-photochemical effect increased the singlet oxygen yields (Φ_Δ=0.35 for 2a, 0.69 for 2b in photochemical study, 0.78 for 2a, 0.97 for 2b in sono-photochemical study).This article may pave the way to achieve high singlet oxygen efficiency.

New soluble 4-(4-formyl-2,6-dimethoxyphenoxy) substituted phthalocyanines: Synthesis, characterization, photophysical and photochemical properties

This work describes the synthesis, spectral and fluorescence properties of bis 4-(4-formyl-2,6-dimethoxyphenoxy) substituted zinc (ZnPc) and magnesium (MgPc) phthalocyanines. The new compounds have been characterized by elemental analysis, UV-Vis, FT-IR, 1H-NMR and mass spectra. Afterward, the effects of including metal ion on the photophysicochemical properties of the complexes were studied in biocompatible solvent DMSO to analyze their potential to use as a photosensitizer in photodynamic therapy (PDT). The fluorescence and singlet oxygen quantum yields were calculated as 0.04–0.15 and 0.70–0.52 for ZnPc and MgPc, respectively. According to the results, MgPc has higher fluorescence quantum yield than ZnPc, while ZnPc has higher singlet oxygen quantum yield than MgPc. The results show that the synthesized complexes can have therapeutic outcomes for cancer treatment.

Photophysicochemical, sonochemical, and biological properties of novel hexadeca-substituted phthalocyanines bearing fluorinated groups

This study presents the preparation of a novel tetra-substituted phthalonitrile (1), namely, 3,6-bis(hexyloxy)-4,5-bis(4-(trifluoromethoxy)phenoxy)phthalonitrile (1) and its metal-free (2)/metal {M = Zn (3), Cu (4), Co (5), Lu(CH₃COO) (6), Lu (7)} phthalocyanines. A series of various spectroscopic methods (UV-vis, FT-IR, mass, and ¹H NMR spectroscopy) were performed for the characterization of the newly synthesized compounds. The potential of compounds 2, 3, and 6 as photosensitizing materials for photodynamic and sonophotodynamic therapies was evaluated by photophysical, photochemical, and sonochemical methods. The highest singlet quantum yields were obtained for the zinc phthalocyanine derivative 3 by performing photochemical and sonochemical methods. In addition, several biological activities of the new compounds 1-7 were investigated. The newly synthesized phthalocyanines exhibited excellent DPPH scavenging activity and also DNA nuclease activity. The antimicrobial activity of the new compounds was evaluated by the disc diffusion assay. Effective microbial cell viability inhibition was observed with phthalocyanine macromolecules. The photodynamic antimicrobial therapy of the phthalocyanines showed 100% bacterial inhibition when compared to the control. They also exhibited significant biofilm inhibition activity against S. aureus and P. aeruginosa. These results indicate that new phthalocyanines are promising photodynamic antimicrobial therapies for the treatment of infectious diseases.

Porphyrin-Containing MOFs and COFs as Heterogeneous Photosensitizers for Singlet Oxygen-Based Antimicrobial Nanodevices

Visible-light irradiation of porphyrin and metalloporphyrin dyes in the presence of molecular oxygen can result in the photocatalytic generation of singlet oxygen (¹O₂). This type II reactive oxygen species (ROS) finds many applications where the dye, also called the photosensitizer, is dissolved (i.e., homogeneous phase) along with the substrate to be oxidized. In contrast, metal-organic frameworks (MOFs) are insoluble (or will disassemble) when placed in a solvent. When stable as a suspension, MOFs adsorb a large amount of O₂ and photocatalytically generate ¹O₂ in a heterogeneous process efficiently. Considering the immense surface area and great capacity for gas adsorption of MOFs, they seem ideal candidates for this application. Very recently, covalent-organic frameworks (COFs), variants where reticulation relies on covalent rather than coordination bonds, have emerged as efficient photosensitizers. This comprehensive mini review describes recent developments in the use of porphyrin-based or porphyrin-containing MOFs and COFs, including nanosized versions, as heterogeneous photosensitizers of singlet oxygen toward antimicrobial applications.

Experimental and theoretical investigation of water-soluble silicon(IV) phthalocyanine and its interaction with bovine serum albumin

Photodynamic therapy (PDT) has drawn a great scientific attention to cancer treatment over the last decades. However, the bottleneck for the PDT is to find good photosensitizers (PSs) with greater water solubility, no aggregation, and fast discharge from the body. Therefore, there are still a big scientific desire for the synthesizing new rational PSs for treatment of cancer by PDT technique. In favor of improving the competence of PDT, an axially bis[4-(diphenylamino-1,1'-biphenyl-4-ol)] substituted silicon(IV) phthalocyanine (3) was converted to its water-soluble quaternized derivative (3Q). Their structures were fully characterized by single-crystal X-ray diffraction, elemental analysis, and different spectroscopic methods such as FT-IR, UV-Vis, MALDI-TOF, and 1H-NMR. The photophysical properties such as fluorescence quantum yields and lifetimes, and the photochemical properties such as singlet oxygen generation of both phthalocyanines were investigated. Ground and excited-state calculations were performed to explain the observed electronic absorption spectra. The addition of the 4-diphenylamino-1,1'-biphenyl-4-ol groups on the axially positions of the silicon(IV) phthalocyanine increased the singlet oxygen quantum yield from 0.15 to around 0.20. Especially quaternized compound 3Q showed high singlet oxygen quantum yield of 0.26 in water solution. In addition, a spectroscopic investigation of the binding behavior of the quaternized silicon (IV) phthalocyanine complex to bovine serum albumin (BSA) is also studied in this work, confirming the possible interaction. Further theoretical calculations were carried out to find out the plausible-binding regions of the BSA protein. Axially bis[4-(diphenylamino-1,1'-biphenyl-4-ol)] substituted silicon(IV) phthalocyanine (3) was converted to its quaternized water soluble derivative (3Q). The photophysical properties such as fluorescence quantum yields and lifetimes, and the photochemical properties such as singlet oxygen generation of both phthalocyanines were investigated. In addition, a spectroscopic investigation of the binding behavior of the quaternized silicon (IV) phthalocyanine complex to bovine serum albumin (BSA) is also studied in this work, confirming the possible interaction. Further theoretical calculations were carried out to find out the plausible binding regions of the BSA protein.