Substituted Silicon Phthalocyanine Research Articles

Novel axially di-substituted natural, cationic and zwitter ionic silicon phthalocyanine derivatives: Synthesis, characterization, sono-photochemical properties

This study focuses on investigating the sono-photophysicochemical properties of recently synthesized and characterized di-axially substituted silicon phthalocyanine complexes, incorporating schiff-base groups and zwitter ions, imparting novel features and potential therapeutic applications. Specifically, our research focused on evaluating the suitability of these complexes for photodynamic therapy (PDT), sonodynamic therapy (SDT), and the emerging field of sono-photodynamic therapy (SPDT). The characterization process involved the application of various analytical techniques, including UV–Vis spectroscopy, infrared (FT-IR) spectroscopy, and proton nuclear magnetic resonance (1H NMR) spectroscopy. Experimental results displayed highly promising outcomes, revealing that the synthesized sensitizers exhibited exceptional efficiency in generating reactive oxygen species, a critical attribute necessary for effective therapeutic interventions. This finding significantly contributes to the development of novel therapeutic agents with enhanced photodynamic and sonodynamic properties. Harnessing the power of light and sound simultaneously through sonophotodynamic therapy offers a unique and synergistic approach, potentially amplifying the therapeutic efficacy of these complexes. The combination of sonochemical and photochemical applications produced better results, for the studied compounds, the quaternized complexes (cationic compounds) showed the higher result. Overall, the results suggest that SPDT is a promising combination therapy for cancer treatment.

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.Graphical

Synthesis of (2-(4-methylthiazol-5-yl) ethoxy)-substituted silicon phthalocyanine and novel green silver nanoparticles: DSSC targets

ABSTRACT In this study, designed as a dye-sensitive solar cell material which, bis-(2-(4-methylthiazol-5-yl) ethoxy) phthalocyaninato silicon (IV) compound (3) was obtained from the chemical reaction of SiPcCl2 and 4-methyl-5-thiazoleethanol. Silver nanoparticles (AgNPs) were synthesized using environmentally friendly and cost-effective green methods using leaf and flower extracts of Corydalis cava(CoV) and Nonea pulla(NP) plants. For the characterization of phthalocyanine compound and silver nanoparticles, Transmission electron microscopy (TEM), 1H NMR, 13C NMR, X-Ray Diffraction (XRD), UV-visible, FT-IR and Mass spectrum devices were used. The power conversion efficiency of without doping compound 3 is 1.20. After doping this compound with CoVAgNPs and NPAgNPs, the power conversion efficiencies increased to 1.74 and 2.10. From this it is clearly seen that silver nanoparticles are effective. It is concluded that better photovoltaic materials can be created by using phthalocyanine and silver nanoparticles together.

AChE/BuChE inhibitory, DNA nuclease and cytotoxic properties of axially 5-[6-(benzyloxy)-2H-1,3-benzoxazin-3(4H)-yl]pentanoxy and 5-[6-(hexyloxy)-2H-1,3-benzoxazin-3(4H)-yl]pentanoxy substituted silicon phthalocyanines

In this work, axially di-5-[6-(benzyloxy)-2H-1,3-benzoxazin-3(4H)-yl]pentanoxy and 5-[6-(hexyloxy)-2H-1,3-benzoxazin-3(4H)-yl]pentanoxy substituted silicon phthalocyanines were synthesized and characterized for the first time. Then, AChE/BuChE inhibitory, supercoiled plasmid pR322 DNA nuclease and cytotoxic properties of the A1-C5-Si and A2-C5-Si were investigated using different methods. The results showed that A1-C5-Si and A2-C5-Si inhibited AChE and BuChE in a concentration-dependent manner whereas galantamine showed higher inhibitory effects that of the compounds. DNA nuclease experiments showed that both compounds did not damage to plasmid DNA when exposed for 30, 60 and 90 min. Both compounds exhibited a concentration-dependent cytotoxicity against SH-SY5Y cells for 24 and 48 h. The cell viabilities were 63.14±12.63% and 54.95±10.38% in the presence of A1-C5-Si at 50 and 100 µM for 24 h. Moreover, the cell viabilities were found to be 53.07±5.83% and 52.33±3.68% for A1-C5-Si and A2-C5-Si at 100 µM, respectively for 48 h.

Synthesis of novel an axially substituted silicon phthalocyanine and determination of its selectivity for Fe 3+

This study includes the synthesis and characterization of an axial phthalocyanine complex. This phthalocyanine was characterized with the aid of NMR, FT-IR, Mass spectrum and UV–vis spectroscopy. The solubility scale of this compound in solvents and its absorption in different solvents were determined. In addition, axial phthalocyanine absorption measurements were made in the same solvent and at different concentrations. The compound was determined to be non-aggregation within the range of measured parameters. Fluorescence absorption, excitation and emission measurements were made in different solvents. The selectivity of Bis-2((4-phenoxyphenyl) diazenyl)benzoic acid) phthalocyaninato silicon (IV) compound to metal ions was investigated by UV-visible absorption spectra. Fe3+ ion selectively differed among the studied metals. This method reveals that it can be used for the optical determination of Fe3+ ion in the fields of environment, food and health.

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.

From P‐type to N‐type: Peripheral fluorination of axially substituted silicon phthalocyanines enables fine tuning of charge transport

AbstractSilicon phthalocyanines (R2‐SiPcs) are a family of promising tunable materials for organic electronic applications. We report the chemistry of the synthesis of axially substituted fluorinated SiPcs (tb‐Ph)2‐FxSiPc (where X = 0, 4, 8, or 16) and explore how the degree of fluorination effects optical and electronic properties. A new treatment with boron trichloride was included to obtain Cl2‐FXSiPcs from F2‐FXSiPcs, activating the axial position for further functionalization. We observed that as the degree of fluorination increased, so did the electron affinity of the compounds, leading to a drop in frontier orbital levels, as measured by electrochemistry and ultraviolet photoelectron spectroscopy (UPS). The deeper energy levels enabled successful (tb‐Ph)2‐F4SiPc and poly [[6,7‐difluoro[(2‐hexyldecyl)oxy]‐[5,8‐quinoxalinediyl]‐2,5‐thiophenediyl]] (PTQ10) blends for organic photovoltaics and photodetectors. All four compounds were incorporated in organic thin‐film transistors (OTFTs), where the degree of fluorination influenced device operation, changing it from p‐type conduction for (tb‐Ph)2‐F0SiPc, to ambipolar for (tb‐Ph)2‐F4SiPc, and n‐type for (tb‐Ph)2‐F8SiPc and (tb‐Ph)2‐F16SiPc. The OTFT devices made with (tb‐Ph)2‐F16SiPc achieved a low average threshold voltage of 7.0 V in N2 and retained its n‐type mobility when exposed to air.

Comparison of sonodynamic, photodynamic and sonophotodynamic therapy activity of fluorinated pyridine substituted silicon phthalocyanines on PC3 prostate cancer cell line

BackgroundSonophotodynamic therapy (SPDT), a combination of photodynamic therapy (PDT) and sonodynamic therapy (SDT), may offer theraputic advantage. The therapeutic effects of sonodynamic, photodynamic, and sonophotodynamic of 5-(trifluoromethyl)-2-thiopyridine substituted silicon phthalocyanine (gy3) and its quaternized derivative (gy3q) were examined in vitro on prostate cancer using PC3 cells. MethodsThe SDT, PDT and SPDT efficiency was determined by using MTT test.Apoptosis mechanism was evaluated by HOPI staining. Results and DiscussionsAccording to MTT results, the phthalocyanines decreased cell viability when compared with a control group. Also, apoptosis measurement data represents that the phthalocyanines would produce much better therapeutic outcomes compare to PDT and SDT by utilizing SPDT. Further studies should be performed to understand the effectiveness of SPDT.

Molecular Engineering of Silicon Phthalocyanine to Improve the Charge Transport and Ammonia Sensing Properties of Organic Heterojunction Gas Sensors

AbstractNovel organic heterostructures fabricated with a bilayer consisting of an axially substituted silicon phthalocyanine (R2‐SiPc) derivative and lutetium bis‐phthalocyanine (LuPc2) are investigated for their ammonia sensing properties. Surface and microstructure characterization of the heterostructure films reveal either compact or highly porous surface topography in (345F)2‐SiPc and Cl2‐SiPc‐based heterostructures, while electrical characterization reveals a strong influence of the axial substituent in R2‐SiPc on NH3 sensing capabilities. Electrical characterization further demonstrates an apparent energy barrier for interfacial charge transport, which is higher in the (345F)2‐SiPc/LuPc2 heterojunction device. In‐depth charge transport studies by impedance spectroscopy further reveal a resistive interface in (345F)2‐SiPc/LuPc2 and faster bulk and interfacial charge transport in Cl2‐SiPc/LuPc2 heterojunction devices. Different interfacial charge transport capabilities and surface topographies affect NH3 sensing properties of the two heterojunction devices, in which (345F)2‐SiPc/LuPc2 reveals a fast and non‐linear response with a limit of detection (LOD) of 310 ppb, while Cl2‐SiPc/LuPc2 exhibits a slow, and linear response to NH3 with LOD of 100 ppb. Finally, different metrological parameters of the two sensors are correlated to the respective gas‐material interactions, in which adsorption and diffusion regimes are modulated by the surface topography and hydrophobicity of the sensing layer.

Comparison of singlet oxygen production of ethyl vanillin substituted silicon phthalocyanine using sonophotodynamic and photodynamic methods

Although Sonophotodynamic Therapy (SPDT) studies, which are a new approach that give better results than Photodynamic Therapy (PDT) in which light and sound are used together, are encountered in the literature, studies in this area are limited. Therefore, this study aimed to demonstrate the potentials of the synthesized compound in PDT and SPDT applications. While the calculated ΦΔ value was 0.50 for compound 1 after light irradiation, this value increased to 0.81 after light and ultrasound irradiation were used together. When the PDT and SPDT methods were compared, it proved that the singlet oxygen production increased significantly when the excitation method was changed to light and ultrasound. This study will enrich the literature on increasing singlet oxygen production by SPDT method.

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 (ΦΔ=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.

Synthesis of a novel axially substituted silicon phthalocyanine sensitizer for efficient singlet oxygen generation by comparing PDT and SPDT studies

This study is based on photodynamic therapy (PDT) and sonophotodynamic therapy (SPDT) which combines photochemical and sonochemical studies, produces high singlet oxygen and provides more effective therapeutic results in the treatment of cancer. For this purpose, a new photosensitizer, naphthoic acid substituted silicon phthalocyanine, is synthesized and characterized by elemental analysis, 1H NMR, FT-IR, MALDI-TOF MS and UV–Vis spectral data and its photophysico-chemical properties are investigated. The singlet oxygen quantum yields that were obtained by photochemical and sono-photochemical methods of the complex, synthesized as a sono-photosensitizer, were calculated and compared by both methods. It was observed that the yield obtained in the sono-photochemical method (ФΔ = 0.74 in DMSO, 0.69 in DMF) was considerably higher than the one obtained in the photochemical method (ФΔ = 0.51 in DMSO, 0.47 in DMF). These results proved that sono-photochemical study remarkably increased the therapeutic effect which is important in cancer treatment.

Improved singlet oxygen generation of axially ruthenium(II) complex substituted silicon(IV) phthalocyanine by sono-photochemical studies

Sono-photodynamic study, which shows an exceedingly high therapeutic outcome compared to photodynamic study, is a new alternative method for the anticancer treatments. However there are not enough related studies in the literature. Therefore, this study initially aimed to design and synthesize ruthenium (II) complex substituted silicon phthalocyanine for a suitable sono-photosensitizer and then to increase singlet oxygen production using sono-photochemical studies. The results showed that the substituent group improved the generation of singlet oxygen quantum yield of silicon (IV) phthalocyanine dichloride, and also the sono-photochemical method increased the yield approximately two times (ΦΔ=0.38 in photochemical study, 0.66 in sono-photochemical study). This article will pave the way for studies that seek to improve sono-photochemical properties.

Pathological complete remission of relapsed tumor by photo-activating antibody-mimetic drug conjugate treatment.

Antibody-mimetic drug conjugate is a novel noncovalent conjugate consisting of an antibody-mimetic recognizing a target molecule on the cancer cell surface and low-molecular-weight payloads that kill the cancer cells. In this study, the efficacy of a photo-activating antibody-mimetic drug conjugate targeting HER2-expressing tumors was evaluated in mice, by using the affibody that recognize HER2 (ZHER2:342 ) as a target molecule and an axially substituted silicon phthalocyanine (a novel potent photo-activating compound) as a payload. The first treatment with the photo-activating antibody-mimetic drug conjugates reduced the size of all HER2-expressing KPL-4 xenograft tumors macroscopically. However, during the observation period, relapsed tumors gradually appeared in approximately 50% of the animals. To evaluate the efficacy of repeated antibody-mimetic drug conjugate treatment, animals with relapsed tumors were treated again with the same regimen. After the second observation period, the mouse tissues were examined histopathologically. Unexpectedly, all relapsed tumors were eradicated, and all animals were diagnosed with pathological complete remission. After the second treatment, skin wounds healed rapidly, and no significant side effects were observed in other organs, except for occasional microscopic granulomatous tissues beneath the serosa of the liver in a few mice. Repeated treatments seemed to be well tolerated. These results indicate the promising efficacy of the repeated photo-activating antibody-mimetic drug conjugate treatment against HER2-expressing tumors.

Bromopropylate Imidazoliumyl Substituted Silicon Phthalocyanine for Mitochondria-Targeting, Two-Photon Imaging Guided in Vitro Photodynamic Therapy.

Maximization of phototoxic damage on tumor is essential for effective anticancer photodynamic therapy (PDT). Highly cancer-cell-organelle-specific delivery of efficient photosensitizers (PSs) in vitro and in vivo is in great demand. In this paper, a novel water-soluble mitochondria targeted cationic bromopropylate imidazoliumyl axially substituted silicon (IV) phthalocyanine (Br-ID-SiPc) is developed to improve PDT efficiency by enhancing the subcellular localization of photosensitizers. Benefiting from the targeting capability of bromopropylate imidazoliumyl, Br-ID-SiPc can selectively accumulate in mitochondria after cellular uptake, this process could be tracked by two-photon imaging. Br-ID-SiPc effectively damaged the circular plasmid DNA of mitochondria and induced HO-8910 cells apoptosis. Our results indicate that Br-ID-SiPc is a potential photosensitizer which can be used as a mitochondria-targeting and two-photon fluorescent imaging molecule for PDT of cancers.

Fluorinated/non-fluorinated triphenylamine axially substituted silicon phthalocyanine: Synthesis and photophysical properties

Three novel fluorinated/ non-fluorinated triphenylamine axially substituted silicon phthalocyanines with AIE character were synthesized. They shows typical emission for phthalocyanine moieties at 678–688 nm as well as an emission at 396 nm for TPA moieties. • Three fluorinated/ non-fluorinated triphenylamine substituted silicon phthalocyanines with AIE character were synthesized and characterized. • Three molecules showed an typical emission for phthalocyanine moieties at 678–688 nm as well as an emission at 396 nm for TPA moieties. • Silicon phthalocyanines with fluorinated and triphenylamine substitutions possessed the highest fluorescence intensity, fluorescence quantum yield and singlet oxygen yield. • Silicon (IV) phthalocyanine with only triphenylamine (TPA) substitutions exhibited obviously AIE character in THF/water mixtures. Three novel fluorinated/non-fluorinated triphenylamine axially substituted silicon phthalocyanines (TPA-FBPA-SiPc, TPA-BPA-SiPc and TPA-SiPc) with aggreagtion-induced emission (AIE) character were synthesized by using silicon phthalocyanine (SiPc) as a core, triphenylamine (TPA) moieties as terminal groups, and fluorinate or non-fluorinate-bisphenol A as bridge groups. Such designed molecules showed typical emissions for SiPc at 675–688 nm as well as emissions for TPA moieties at 396 nm. Their photophysical and photochemical properties are affected by both the fluorinate-bisphenol A substitutions and TPA substitutions. TPA-FBPA-SiPc with both fluorinate-bisphenol A and TPA substitutions possessed the highest fluorescence intensity, fluorescence quantum yield as well as singlet oxygen yield. Besides, TPA-SiPc with only TPA substitutions could not only avoid the aggregation-caused quenching of phthalocyanines but also exhibite obvious AIE character in THF/water mixtures due to the presence of TPA moieties. This work could provide some useful structure and photophysical properties relationship for design novel phthalocyanine for photodynamic therapy.

Carbonic anhydrase inhibition and antioxidant activity of the axially naphthoxazin group substituted silicon phthalocyanines

Silicon phthalocyanines are an interesting subclass of phthalocyanines. They are abundant and have extremely low toxicity levels. The low solubility of silicon phthalocyanine is the major obstacle to its use in many different applications. Therefore, in a previous study, two axially substituted silicon phthalocyanines were synthesized to increase their solubility. In this study, these axially substituted silicon phthalocyanines were evaluated for carbonic anhydrase inhibition and antioxidant activities. The carbonic anhydrase (CA) inhibition potential of silicon phthalocyanines was evaluated by esterase activity. The antioxidant activity was tested by 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging and ferric ion (III) reducing/antioxidant power (FRAP) assays. The silicon phthalocyanines had significant CA inhibitory activity [50% inhibitory values (IC50): 495 ± 12.74 nM and 857 ± 13.03 nM for H4-Si and H3-Si, respectively]. According to the antioxidant studies, 50% scavenging concentration (SC50) values of DPPH• assay were 2.29 ± 0.06 µg/mL and 1.39 ± 0.43 µg/mL for H3-Si and H4-Si and Trolox Equivalent Antioxidant Capacity (TEAC) values of FRAP test were 259.33 ± 48.27 µM and 342.00 ± 44.40 for H3-Si µM and H4-Si, respectively. Consequently, silicon phthalocyanine compounds are considered to have great potential for their use in various fields such as food and medicine.

Axially Substituted Silicon Phthalocyanine Payloads for Antibody–Drug Conjugates

AbstractIR700, a silicon phthalocyanine (SiPc) photosensitizer, is an antibody–drug conjugate payload used clinically. It is, however, the sole SiPc payload to date, possibly due to the difficulty of its synthesis, resulting from its asymmetric phthalocyanine skeleton. Here, we report a new axially substituted SiPc payload that is more easily synthesized. Trastuzumab conjugated with the SiPc showed light- and antigen-dependent cytotoxicity in HER2-overexpressing cancer cell lines.

Investigation of singlet oxygen efficiency of di-axially substituted silicon phthalocyanine with sono-photochemical and photochemical studies

Sono-photodynamic therapy (SPDT) is a favorable new modality for the treatment of the tumor cells. Although SPDT improves the therapeutic outcomes in cell applications, unlike PDT, SPDT studies are insufficient. In this study, to contribute to the development of SPDT, a promising sensitizer was synthesized, characterized, and analyzed photophysico-chemical properties. Afterwards, the singlet oxygen quantum yield of the sensitizer was calculated by both photochemical and sono-photochemical studies. When the methods are compared, the sono-photochemical studies (ΦΔ = 0.71 in DMSO, 0.65 in DMF) were found more effective than the photochemical studies (ΦΔ = 0.47 DMSO, 0.41 in DMF) in terms of producing singlet oxygen. This report will pave the way for the synthesis of new sensitizers to be used in SPDT.

Fluorescence properties in different solvents and synthesis of axially substituted silicon phthalocyanine bearing bis-4-tritylphenoxy units

Abstract In this present study, a new axially bis-4-tritylphenoxy substituted silicon phthalocyanine compound was synthesized and characterized using infrared, mass, electronic absorption and nuclear magnetic resonance spectroscopy. Fluorescence and absorption spectra studies of the disubstituted silicon phthalocyanine complex were conducted on the chloroform, dimethyl formamide, dimethyl sulfoxide and tetrahydrofuran solutions. The findings of the fluorescence studies demonstrated that the compound has fluorescence spectra in the different solvents. The effects of the substitution with axially bis-4-tritylphenoxy functionalized groups on these parameters were also compared with the previously synthesized axially disubstituted silicon phthalocyanines. These results proved that the compound has different fluorescence properties in the different solvents.