The photodynamic antimicrobial chemotherapy activities of azaBODIPY dyes and their gold nanoparticle conjugates.

This synthesis and photophysicochemical properties of two 2,6-diiodinated azaBODIPY dyes with thiomethylphenyl groups at the distal positions and phenyl (1) and naphthyl (2) rings at the proximal positions are reported. The dyes were conjugated to gold nanoparticles (1-AuNPs and 2-AuNPs) to enhance their aqueous solubility for biomedical applications. Iodination at the 2,6-positions resulted in an enhancement of singlet oxygen generation, with singlet oxygen quantum yield (Φ) values of 0.

Synthesis and evaluation of multi-quaternary ammonium cation-functionalized BODIPYs with photodynamic antibacterial effects.

As an alternative of antibiotic therapy against drug-resistance or even multi-drug-resistant bacteria, antimicrobial photodynamic therapy (aPDT) is a promising therapeutic approach for cutaneous/oral localized infections as well as an efficient protocol for disinfection of blood products. In this study, a series of BODIPY derivatives modified with multi-quaternary ammonium cations were designed and synthesized. Density functional theory (DFT) showed that the ΔE values of new compounds were significantly reduced compared to the reference compound BDP-1.

Effects of central metals on sugar decorated tetrakis-(4-methylthiophenyl) porphyrin considered for use in photodynamic therapy.

This study focuses on the synthesis of sugar decorated porphyrins and their gold nanoparticle conjugates as photosensitizers for photodynamic therapy (PDT). Linking the sugar to the porphyrins imparted water solubility to the latter. The conjugation to sugar molecules enhanced the singlet oxygen quantum yield and improved the cellular uptake and therefore, their phototoxicity in some cases.

Tetracationic tetraaryltetranaphtho[2,3]porphyrins for photodynamic inactivation against Staphylococcus aureus biofilm.

Antimicrobial photodynamic therapy (aPDT) has emerged as a promising strategy for addressing bacterial infections, particularly those involving biofilm formation. The electrostatic attraction between the negatively charged bacterial cell walls and the cationic charges of photosensitizers facilitates the accumulation of PSs on bacterial surfaces, thereby enhancing aPDT efficacy. In this study, three series of tetracationic tetraaryltetranaphtho[2,3]porphyrins (TNPs), each incorporating different cationic groups with alkyl chains of varying lengths, were designed and synthesized.

Bismuth doped carbon nanospheres conjugated to boronated porphyrins for photodynamic therapy.

Novel 4- (5,10,15)-tris-boronphenyl-20-(4-formylphenoxy) porphyrin (complex 1) and its Zn-metalated derivative (complex 2) were synthesized and conjugated to bismuth doped carbon nanospheres (BiCNS) through non-covalent bonds (π-π). The conjugation of BiCNS to porphyrin complexes enhanced the singlet oxygen production of porphyrin complexes, as it was observed that porphyrin complex 1 gave a singlet oxygen quantum yield (Φ) value of 0.17 and complex 2 gave Φ of 0.

Phthalocyanine based metal organic frameworks for electrochemical detection of human epidermal growth factor receptor 2.

Herein, we report on the development of a phthalocynaine based metal organic frameworks (MOF) for the detection of human epidermal growth factor receptor 2 (HER2). Phthalocyanines (Pcs) exhibit good redox properties, hence their utilization as precursors for the synthesis of Pc based MOFs. The successful preparation of the MOF was confirmed using X-ray powder diffraction (XRD), thermogravimetric analysis (TGA), Fourier transform infrared (FT-IR) spectroscopy, X-ray photoelectron spectroscopy (XPS), and Brunner Emmet Teller (BET) analysis.

BODIPY dyes for optical limiting applications on the nanosecond timescale.

Since 2017, the Institute for Nanotechnology Innovation at Rhodes University has studied the optical limiting properties of boron dipyrromethene (BODIPY) dyes with respect to high-intensity nanosecond timescale laser pulses. Concerns over the irresponsible use of laser pointers in the context of aviation safety have provided a need for materials that can readily transmit light under ambient conditions while rapidly attenuating intense incident laser pulses. The structural flexibility of the BODIPY chromophore facilitates the red shift of the main BODIPY spectral band that typically lies at 500 nm to the red end of the visible and the near-infrared through the introduction of vinylene groups at the 3,5-positions or an aza-nitrogen atom.

Bioengineering of one dimensional hierarchical CuS hollow nanotubes for non-enzymatic glucose sensing applications.

Herein, a novel and facile eco-friendly green chemistry approach has been devised at room temperature for synthesis of 1D hierarchical CuS hollow nanotubes on Cu substrate volatile organosulfur compounds from L for non-enzymatic glucose detection. Field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), energy dispersive X-ray spectroscopy (EDX), and X-ray spectroscopy (XPS) were employed to characterize the surface morphology, structural phase, compositional, and chemical states of the obtained samples, respectively. The SEM results confirm the formation of 1D hierarchical CuS hollow nanotubes.

Blue-Light-Activated Water-Soluble Sn(IV)-Porphyrins for Antibacterial Photodynamic Therapy (aPDT) against Drug-Resistant Bacterial Pathogens.

Antimicrobial resistance has emerged as a global threat to the treatment of infectious diseases. Antibacterial photodynamic therapy (aPDT) is a promising alternative approach and is highly suitable for the treatment of cutaneous bacterial infections through topical applications. aPDT relies on light-responsive compounds called photosensitizer (PS) dyes, which generate reactive oxygen species (ROS) when induced by light, thereby killing bacterial cells.

Trinuclear ruthenium(II) polypyridyl complexes: Evaluation as photosensitizers for enhanced cervical cancer treatment.

Trinuclear ruthenium(II) polypyridyl complexes anchored to benzimidazole-triazine / trisamine scaffolds were investigated as photosensitizers for photodynamic therapy. The trinuclear complexes were noted to produce a significant amount of singlet oxygen in both DMF and aqueous media, are photostable and show appreciable emission quantum yields (ɸ). In our experimental setting, despite the moderate phototoxic activity in the HeLa cervical cancer cell line, the phototoxic indices (PI) of the trinuclear complexes are superior relative to the PIs of a clinically approved photosensitizer, Photofrin®, and the pro-drug 5-aminolevulinic acid (PI: >7 relative to PI: >1 and PI: 4.

Photodynamic antimicrobial chemotherapy activities of phthalocyanine-antibiotic conjugates against bacterial biofilms and interactions with extracellular polymeric substances.

This study sheds light on how to rationally design efficient photodynamic antimicrobial chemotherapy (PACT) agents by covalently linking phthalocyanines (Pcs) as photosensitizers with an antibiotic: Ciprofloxacin (CIP). Pcs used are zinc (II) 3-(4-((3,17,23-tris(4-(Benzo(d)thiazol-2-yl] thiol) phthalocyanine-9-yl) oxy) phenyl) propanoic acid (1) and zinc (II) 3-(4-(3,17,23-tris(3-(4-(triphenylphosphine) butyl) benzo[d]thiazol-3-ium bromide phthalocyanine-9-yl) oxy) phenyl) propanoic acid (2). High singlet oxygen quantum yields are observed in the presence of CIP.

The photodynamic activity properties of a series of structurally analogous tetraarylporphyrin, chlorin and N-confused porphyrin dyes and their Sn(IV) complexes.

A series of tetraarylporphyrin, -chlorin and N-confused porphyrin dyes with 4‑methoxy‑meso-aryl rings (1-Por, 1-Chl and 1-NCP) and their Sn(IV) complexes (1-SnPor, 1-SnChl and 1-SnNCP) have been synthesized and characterized. The heavy atom effect of the Sn(IV) ion results in relatively high singlet oxygen quantum yield values of 0.67, 0.

The application of Sn(IV)Cl and In(III)Cl porphyrin-dyed TiO nanofibers in photodynamic antimicrobial chemotherapy for bacterial inactivation in water.

The World Health Organization has reported that antimicrobial resistance is one of the top 10 health threats that humanity faces today. Due to this, alternative therapies to the common antimicrobials are being explored and among these is photodynamic antimicrobial chemotherapy, where a combination of light, a photosensitizer and reactive oxygen species can be used to target microbial cells. In this research, free base, tin (IV) and indium (III) tetramethoxyporphyrins photosensitizers are adsorbed onto inorganic titanium dioxide nanofibers in an effort to create reusable fibers that are effective against Staphylococcus aureus.

The development of folate-functionalised palladium nanoparticles for folate receptor targeting in breast cancer cells.

Folate receptor-targeted therapy has excellent prospects for the treatment of breast cancer. A non-toxic concentration of folate-conjugated palladium-based nanoparticles was used to target the overexpressed folate receptor on breast cancer cells. The folate-conjugated nanoparticles were tailored to accumulate selectively in cancer cells relative to normal cells via the folate receptor.

Single vs sandwich aptamers: Towards the detection of human epidermal growth factor receptor 2 using composites of phthalocyanine and nanoparticles.

The superiority of the sandwich over a single aptamer based aptasensor assay for the detection of the human epidermal growth factor receptor 2 (HER2) is demonstrated for the first time. Cobalt tris-3,5 dimethoxy-phenoxy pyridine (5) oxy (2)- carboxylic acid phthalocyanine (CoMPhPyCPc) and sulphur/nitrogen doped graphene quantum dots (SNGQDs) and cerium oxide nanoparticles (CeONPs) nanocomposite (SNGQDs@CeONPs) were used for electrode modification of glassy carbon electrode (GCE) both individually and combined to form the substrates: GCE/SNGQDs@CeONPs, GCE/CoMPhPyCPc and GCE/SNGQDs@CeONPs/CoMPhPyCPc. The designed substrates were used as immobilization platforms for the amino functionalized HB5 aptamer for the development of both single and sandwich aptasensor assays.

Fibrous TiO Alternatives for Semiconductor-Based Catalysts for Photocatalytic Water Remediation Involving Organic Contaminants.

Water decontamination remains a challenge in several developed and developing countries. Affordable and efficient approaches are needed urgently. In this scenario, heterogeneous photocatalysts appear as one of the most promising alternatives.

The Photodynamic Anticancer and Antibacterial Activity Properties of a Series of -Tetraarylchlorin Dyes and Their Sn(IV) Complexes.

A series of tetraarylchlorins with 3-methoxy-, 4-hydroxy- and 3-methoxy-4-hydroxyphenyl -aryl rings (--Chl) and their Sn(IV) complexes (--SnChl) were synthesized and characterized so that their potential utility as photosensitizer dyes for use in photodynamic therapy (PDT) and photodynamic antimicrobial chemotherapy (PACT) can be assessed. The photophysicochemical properties of the dyes were assessed prior to in vitro PDT activity studies against MCF-7 breast cancer cells through irradiation with Thorlabs 625 or 660 nm LED for 20 min (240 or 280 mW·cm). PACT activity studies were performed against both planktonic bacteria and biofilms of Gram-(+) and Gram-(-) upon irradiation with Thorlabs 625 and 660 nm LEDs for 75 min.

Sn(IV)-porphyrinoids for photodynamic anticancer and antimicrobial chemotherapy.

Photodynamic therapy (PDT) is a mode of treatment for different types of cancers, which involves a nontoxic photosensitizer (PS), a light source to activate the PS, and ground-state molecular oxygen (O). Light activation of the PS leads to the generation of reactive oxygen species (ROS), which initiates a toxic effect on the surrounding cellular substrates, thereby destroying the cancerous cells. The commercially used PDT drug Photofrin which is a tetrapyrrolic porphyrin-based photosensitizer has drawbacks such as aggregation in water, prolonged skin photosensitivity, variability in chemical compositions, and minimal absorbance in the red-light region.

Photoantimicrobial activity of Schiff-base morpholino phthalocyanines against drug resistant micro-organisms in their planktonic and biofilm forms.

Antimicrobial photodynamic inactivation (aPDI) is a treatment for the eradication of drug-resistant micro-organisms. One of the advantages of this technique, is that there is minimal possibility of microbial resistance. Hence, herein, the preparation and characterization of novel neutral and cationic morpholine containing Schiff base phthalocyanines are reported.

Evaluation of the antibacterial activity of gallic acid anchored phthalocyanine-doped silica nanoparticles towards Escherichia coli and Staphylococcus aureus biofilms and planktonic cells.

In this work, we have described the synthesis of phthalocyanine complexes Zn(II) tetrakis 4-(5-formylpyridin-2-yl)oxy) phthalocyanine (2), Zn(II) tetrakis-1‑butyl‑4-(2-(6- (tetra-phenoxy)pyridin-3-yl) vinyl)pyridin-1-ium phthalocyanine (3) and Zn(II) tetrakis 1‑butyl‑5-(2-(1-butylpyridin-1-ium-4-yl)vinyl)-2-(tetra-phenoxy)pyridin-1-ium phthalocyanine (4). The effect of a varying number of charges when the Pc complexes are alone or grafted in gallic acid (GA) tagged silica nanoparticles on photodynamic antimicrobial chemotherapy (PACT) is investigated toward Staphylococcus aureus (S.aureus) and Escherichia coli (E.

Methylthiophenyl- and Methylthiobiphenyl-Substituted AB Cocorroles: Modulating Electrocatalyzed Hydrogen Evolution Reactions on Surface-Modified Gold Electrodes.

Four AB-type Cocorroles () with electron-donating/withdrawing substituents at the A -aryl substituents and a 4-(methylthio)phenyl ring at the B position have been synthesized and characterized, along with a series of -extended Cocorroles (-) with 4'-(methylthio)biphenyl moieties. The electronic structures and structure-property relationships of the dyes have been analyzed by comparing their redox and optical properties to trends predicted in density functional theory calculations. Au electrodes surface-modified with - and - are highly efficient catalysts for electrocatalyzed hydrogen evolution reactions, and the electrocatalytic properties can be readily modulated by fine-tuning the electronic structure of the Cocorrole and the distance between the "Au-S" bond and Co center.

The in-vitro proliferation-suppression of MCF-7 and HeLa cell lines mediated by differently substituted ionic phthalocyanines in sonodynamic therapy supplemented-photodynamic therapy.

This work focuses on the study of the effects of the ultrasonic frequency (MHz) and power (W.cm) on the stability, reactive oxygen species yields and cytotoxicity activities of differently substituted ionic phthalocyanines (Pcs) in sonodynamic therapy (SDT). Four ultrasonic parameters were investigated: Par I (1 MHz: 1 W.

A hypoxia responsive silicon phthalocyanine containing naphthquinone axial ligands for photodynamic therapy activity.

A liposome loaded‑silicon (IV) phthalocyanine (SiPc) containing naphthoquinone axial ligands as hypoxia-responsive a prodrug-like moieties (Prodrug-SiPc), is herein reported. With the help of computational methods, this study assessed the photophysical, photochemical and electrochemical redox properties of the Prodrug-SiPc to elucidate the relationship between material structure and properties. The attachment of the axial quinoid moieties endowed the Prodrug-SiPc with Type I/II photochemical and prodrug-like properties.

Co phthalocyanine mediated electrochemical detection of the HER2 in the presence of Au and CeO nanoparticles and graphene quantum dots.

In this work, cobalt tetra phenoxy acetic acid phthalocyanine (CoTAPc) is investigated as an electron mediator, immobilization platform for an HB5 aptamer and to enhance the electrochemical signal for the detection of human epidermal growth factor receptor 2 (HER2). Furthermore, the CoTAPc was combined individually with sulphur/nitrogen doped graphene quantum dots (SNGQDs), gold nanoparticles (AuNPs) and cerium oxide nanoparticles (CeONPs), on a glassy carbon electrode (GCE) via sequential adsorption. The CoTAPc and SNGQDs were also π-π stacked, used for electrode modification similarly to the rest of the other surfaces and applied towards the electrochemical detection of HER2.