Search

• A nanoassembly containing zinc phthalocyanine, detonated nanodiamonds and halogenated BODIPY is presented. • The composites shows high singlet oxygen quantum yield as high as 0.50 in water. • Zeta potential studies of the composite show that it is most stable at pHs 2, 4 and 7 and 80 °C. • The composite showed high photodynamic therapy with a low cell viability of 21 ± 5%. This work reports on the synthesis of nanoassemblies of supramolecular hybrids containing detonated nanodiamonds (DNDs) covalently linked to halogenated BODIPY (DNDs-BODIPY) by an amide bond, followed by π–π stacking of 2,9,16,23-tetrakis[4-(N -methylpyridyloxy)]-phthalocyanine (ZnTPPcQ) on the DNDs-BODIPY conjugate, to form nanoassembly represented as ZnTPPcQ-DNDs-BODIPY. ZnTPPcQ-DNDs-BODIPY has a higher singlet oxygen quantum yield of 0.50 in water. Therefore, the construction of a three component photodynamic therapy agent (ZnTPPcQ-DNDs-BODIPY) as a single photosentisiser improved singlet quantum yields of the Pc. Zeta potential studies of ZnTPPcQ-DNDs-BODIPY under various temperatures, concentrations and pH conditions, showed the conjugate is more stable at pHs 2, 4 and 7 and at high concentrations (50 μg/mL) and temperatures (80 °C). ZnTPPcQ-DNDs-BODIPY showed high photodynamic therapy (PDT) activity with a low MCF-7 cell viability of 21 ± 5% when compared to 31 ± 2%, 30 ± 2% and 28 ± 2% cell viability at the highest tested concentration of 50 μg/mL for DNDs, ZnTPPcQ-DND and DNDs-BODIPY, respectively. [ABSTRACT FROM AUTHOR]

Highlights • Zinc (1) and indium (2) phthalocyaninanes are linked to gold speckled silica (GSS) nanoparticles. • The conjugates afforded an increase in singlet oxygen quantum yields when compared to phthalocyanines alone. • 2 -GSS showed enhanced photodynamic therapy activity when as compared to 2 and GSS alone. Abstract This work reports on the linkage of 2(3),9(10),16(17),23(24) tetrakis [(benzo[ d ]thiazol-2-yl phenoxy) phthalocyaninato] zinc(II) (1) and indium(III) chloride (2) to gold speckled silica (GSS) nanoparticles via gold to sulphur (Au-S) and gold to nitrogen (Au-N) self-assembly to form the conjugates: 1 -GSS and 2 -GSS. The formed conjugates were characterized using microscopic and spectroscopic techniques, and the photophysicochemical properties and photodynamic therapy (PDT) activity against human breast adenocarcinoma cell line (MCF-7 cells) were studied. The conjugates afforded decrease in fluorescence quantum yields with corresponding increase in triplet and singlet oxygen quantum yields when compared to phthalocyanines alone. Singlet oxygen is cytotoxic to cancer cells hence it is important for PDT. The in vitro dark toxicity of complex 2 and 2 -GSS against MCF–7 cells showed ≥93% viable cells within concentration ranges of 10–160 μg/mL. 2 –GSS showed enhanced PDT activity with less than 50% viable cells at 80 μg/mL as compared to 2 and GSS alone which showed >60% viable cells within 10–160 μg/mL. The observed improvements in the PDT activity of 2 -GSS could be attributed to the high singlet oxygen generation of 2 -GSS compared to 2 alone in addition to the phototoxicity of GSS. [ABSTRACT FROM AUTHOR]

• Cationic Zn phthalocyanines are combined with the antibiotic, ciprofloxacin (CIP). • The complexes are used for photodynamic antimicrobial chemotherapy against bacteria. • Square wave voltammetry was used to analyse the Pc-CIP uptake by bacteria biofilms. • Raman spectra are used to identify the components of the breakdown of the biofilm. 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. Square wave voltammetry was used to analyse the Pc-CIP uptake by bacteria biofilms of Streptococcus pneumoniae (S. pneumonia) and Escherichia coli (E. coli). Electrochemical impedance spectroscopy and scanning electron spectroscopy were used to study the stability of the biofilms in the presence Pc-CIP complexes and when exposed to light. Raman and time of flight-secondary ion mass spectrometry (TOF-SIMS) are used to identify the breakdown of cellular components of the biofilm and penetration of the Pc-CIP into the biofilms, respectively. [Display omitted] [ABSTRACT FROM AUTHOR]

• New Sn(IV) chlorins and N-confused porphyrins have been synthesized. • Photodynamic activities against MCF-7 cancer cells have been assessed. • Enhanced IC 50 values were obtained relative to the analogous Sn(IV) porphyrins. • Photodynamic activities against Gram-(+) and -(−) bacteria have been assessed. • High Log 10 reductions for Sn(IV) complexes in the absence of cationic charges. 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, 0.71 and 0.85 for 1 -SnPor, 1 -SnChl and 1 -SnNCP, respectively. The photodynamic activities of 1 -Por, 1 -Chl, 1 -NCP, 1 -SnPor, 1 -SnChl and 1 -SnNCP were determined against MCF-7 breast cancer cells through illumination with Thorlabs 625 or 660 nm (240 or 280 mW.cm−2) light emitting diodes (LEDs) for 20 min. The IC 50 values for 1 -SnChl and 1 -SnNCP lie between 1.4 − 6.1 and 1.6 − 4.8 µM upon photoirradiation with the 660 and 625 nm LEDs, respectively, while higher values of >10 µM were obtained for 1 -SnPor and the free base dyes. In a similar manner, 1 -SnChl and 1 -SnNCP were found to also have significantly higher photodynamic antimicrobial activity against planktonic Gram-(+) Staphylococcus aureus and Gram-(−) Escherichia coli bacteria than the other dyes studied. Upon illumination with Thorlabs 625 and 660 nm LEDs for 75 min, Log 10 reduction values of 7.62 and > 2.40−3.69 were obtained with 1 and 5 µM solutions, respectively. [Display omitted] [ABSTRACT FROM AUTHOR]

• Sn/In porphyrins photosensitisers are adsorbed onto inorganic titanium dioxide nanofibers. • The decorated nanofibers are used for photodynamic antimicrobial chemotherapy against S. aureus. • The Sn porphyrin exhibited better activity when compared to in derivative. • Sn porphyrin exhibited 100% bacterial inhibition after a 30 min irradiation period. 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 photodynamic antimicrobial chemotherapy studies indicate that the metalloporphyrin adsorbed nanofibers exhibit good photodynamic antimicrobial activity against Staphylococcus aureus where the Cl 2 Sn(IV) tetramethoxyporphyrin dyed TiO 2 exhibited 100% bacterial inhibition after a 30 min irradiation period. [Display omitted] [ABSTRACT FROM AUTHOR]

• Neutral (2,3) and cationic (4,5) morpholine containing Schiff base phthalocyanines are reported. • The complexes are used for antimicrobial photodynamic inactivation (aPDI) against bacteria and fungi. • cationic phthalocyanines showed excellent aPDI activity against planktonic cells of all micro-organisms. • Biofilms were susceptible when treated with 200 µM of cationic Pcs at 108 J/cm2. 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. The cationic complexes gave moderate singlet oxygen quantum yields (Φ Δ) of ∼0.2 in aqueous media. Conversely, the neutral complexes generated very low Φ Δ values making them very poor candidates for antimicrobial studies. The cationic phthalocyanines showed excellent photodynamic activity against planktonic cells of all micro-organisms (Candida albicans, Escherichia coli, Klebsiella pneumoniae, Staphylococcus aureus, Salmonella enterica subspecies enterica serovar Choleraesuis , vancomycin-resistant Enterococcus faecium , and methicillin-resistant Staphylococcus aureus). The efficiency of aPDI was shown to be both concentration and light-dose-dependent. Mono biofilms were susceptible when treated with 200 µM of cationic Pcs at 108 J/cm2. However, ∼10% of the mixed biofilm survived after treatment. [Display omitted] [ABSTRACT FROM AUTHOR]

• Phthalocyanines are embedded in silica nanoparticles grafted with gallic acid. • The conjugates are employed for photodynamic antimicrobial chemotherapy. • Planktonic and biofilm forms of S.aureus and E.coli are employed. • High log reduction value of 8.60 against E.coli biofilms, was obtained. 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.coli) in both planktonic and biofilm forms. Complex 4 , bearing a total of 8 cationic charges, displayed the highest activity with log CFU (colony forming units) values of 8.60 and 6.42 against E.coli and S.aureus biofilms, respectively. The surface stability of E.coli and S.aureus biofilms in the presence of 4 and its conjugate was analyzed using cyclic voltammetry. Scanning electron microscopy (SEM) and Raman spectra are also used to study the conformational and biochemical changes within biofilm upon subjecting them to PACT. [Display omitted] [ABSTRACT FROM AUTHOR]

• Photodynamic antimicrobial chemotherapy (PACT) is coupled with an antibiotic, ciprofloxacin (CIP) for bacterial inactivation. • Cationic porphyrin (1) and a phthalocyanine (2) were employed. • Applying PACT followed by the antibiotic treatment led to reduction in the biofilm cell survival of S. aureus and E. coli biofilms. • High log 10 reduction values of 7.05 and 7.20 on S. aureus and E. coli, respectively, at low concentrations were obtained. Photodynamic antimicrobial chemotherapy (PACT) coupled with an antibiotic, ciprofloxacin (CIP), was investigated using two indium metallated cationic photosensitizers, a porphyrin (1) and a phthalocyanine (2). Applying PACT followed by the antibiotic treatment led to a remarkable reduction in the biofilm cell survival of two antibiotic-resistant bacterial strains, S. aureus (Gram-positive) and E. coli (Gram-nenative). Treating both bacteria strains with PACT alone showed no significant activity at 32 µM with 15 min irradiation, while CIP alone exhibited a minimum biofilm inhibition concentration (MBIC) at 4 and 8 µg/mL on S. aureus and E. coli, respectively following 24 h incubation. The combined treatment resulted in the complete eradication of the matured biofilms with high log 10 reduction values of 7.05 and 7.20 on S. aureus and E. coli, respectively, at low concentrations. It was found that 15 min PACT irradiation of 8 µM of complexes (1 and 2) combined with 2 µg/mL of CIP have a 100% reduction of the resistant S. aureus biofilms. Whereas the total killing of E. coli was obtained when combining 8 µM of complex 1 and 16 µM of complex 2 both combined with 4 µg/mL of CIP. [ABSTRACT FROM AUTHOR]

• Neutral and cationic zinc and indium substituted phthalocyanines are linked to ZnO nanoparticles. • The conjugates exhibited good photodynamic antimicrobial chemotherapy activity. • log reduction values of ∼ 8 were obtained for planktonic cells of S. aureus, E. coli , and C. albicans. • For biofilms log reduction values >3 for both S. aureus and E. coli were obtained. The synthesis and characterization of neutral zinc and indium substituted mercaptobenzothiazole substituted phthalocyanines (Pcs) and their respective cationic derivatives are presented. The phthalocyanines were further covalently linked to two differently shaped amino-functionalized ZnO nanoparticles (ZnONPs): namely nanospheres (NH 2 -ZnONSp), and nanopyramids (NH 2 -ZnONPy), to form corresponding nanoconjugates. The photophysicochemical properties of each nanocomposite were determined, and the Pc-ZnONPs produced high singlet oxygen quantum yields. The photodynamic antimicrobial chemotherapy activity was determined using planktonic and biofilm cells of Staphylococcus aureus (S. aureus), Escherichia coli (E. coli) , and Candida albicans (C. albicans). The conjugates of the cationic Pc derivatives with ZnONPy produced the highest log reduction values (∼ 8 and above) with the complete elimination of all planktonic cells at 0.45 kJ/cm2 for S. aureus and at 0.9 kJ/cm2 for E. coli, and C. albicans. For biofilms log reduction values >3 for both S. aureus and E. coli were obtained. The conjugates of the cationic Pc derivatives with NH 2 -ZnONPy showed great potential in eradicating mixed microbial biofilms. [Display omitted] [ABSTRACT FROM AUTHOR]

• Photodynamic antimicrobial chemotherapy is effective in photoinactivation of pathogenic microbes. • TD-DFT calculations. • Symmetric cationic porphyrin synthesised and conjugated to GQDs via noncovalent (π-π) interaction. • Photosensitizers induce cytotoxic effects on microbes by generating reactive oxygen species. Pathogenic microorganisms may continue causing infection through the transfer of antibiotic resistance genes. As a result, the efficacy of pharmaceuticals in microbial inactivation is deteriorating. The present study was conducted to investigate the antimicrobial activity of neutral and quaternized free base and Zn 5,10,15,20-tetra(pyridin-3-yl) porphyrins on Escherichia coli (E. coli), a gram-negative bacterium that causes cholecystitis, pneumonia and urinary tract infections. Conjugation of the porphyrin to graphene quantum dots (GQDs) was implemented to enhance photocatalysis and reactive oxygen species generation. Density functional theory (DFT) geometry optimizations for free base and Zn porphyrin based on the B3LYP (Becke 3-Parameter (Exchange), Lee, Yang and Parr) functional of the Gaussian09 program package and Time-dependent density-functional theory (TD-DFT) calculations of the associated UV-visible absorption spectra are reported to analyse the electronic structure and optical properties of the porphyrins. The TD-DFT calculations showed that for both porphyrins the value of highest occupied molecular orbital (ΔHOMO) is greater than that of lowest unoccupied molecular orbital (ΔLUMO) which tells that there is no unusual splitting of (LUMO) orbitals which may be caused by systematic error in TD-DFT calculations. Due to the red shift in the spectrum of ZnT(3-Py)P and the ΔLUMO being higher, the HOMO-LUMO gap was expected to be lower than that of H 2 T(3-Py)P. The photophysical properties and Photodynamic antimicrobial chemotherapy activities of these nanoconjugates were investigated. The highest Φ Δ was that of Q-ZnT(3-Py)P- GDQs at 0.69 with the log reduction of 9.42. [ABSTRACT FROM AUTHOR]

• Cationic Zn phthalocyanines were obtained by alkylation of pyridinyloxy groups containing nitrogen at the ortho, meta, and para positions. • The meta and para substituted complexes demonstrate high singlet oxygen quantum yields. • The cationic Pcs demonstrate good planktonic antibacterial activity towards S. aureus and E. coli with highest log reduction. • The complexes also demonstrate a significant decrease in the viability of biofilms of S. aureus and E. coli. Cationic Zn phthalocyanine complexes were derived by alkylation reaction of tetra-(pyridinyloxy) phthalocyanines (Pcs) at the ortho, meta, and para positions to form Zn (II) tetrakis 3-(4-(2-pyridin-1-ium-1-yl) butyl)-2-mercapto-4,5-dihydrothiazol-3-ium phthalocyanine (2), Zn (II) t etrakis 3-(4-(3-pyridin-1-ium-1-yl) butyl)-2-mercapto-4,5-dihydrothiazol-3-ium phthalocyanine (4) and Zn (II) t etrakis 3-(4-(4-pyridin-1-ium-1-yl) butyl)-2-mercapto-4,5-dihydrothiazol-3-ium phthalocyanine (6). The photophysicochemical behaviors of the Pc complexes were assessed. The meta and para-substituted complexes gave high singlet oxygen quantum yields. The cationic Pcs demonstrated good planktonic antibacterial activity against Staphylococcus aureus and Escherichia coli with the high log reduction values of 9.29 and 8.55, respectively. The cationic complexes also showed a significant decrease in the viability of in vitro biofilms after photo-antimicrobial chemotherapy at 100 µM for both Staphylococcus aureus and Escherichia coli biofilms. [ABSTRACT FROM AUTHOR]

• Folic acid is linked to nitrogen doped graphene quantum dots (to form FA-NGQDs). • Zinc porphyrin (2), and its quaternized derivative (3) are π-π onto FA-NGQDs. • 3-FA-NGQDs has higher photodynamic Therapy activity compared to 2-FA-NGQDs. Zinc tetra morpholine porphyrin (complex 2), and its quaternized derivative (complex 3) were synthesized and conjugated to folic acid decorated nitrogen doped graphene quantum dots (FA-NGQDs) through π − π stacking to study their photodynamic therapy (PDT) efficacy. Photophysiochemical properties of complexes 2, 3 , and their conjugates (2 -FA-NGQDs, 3 -FA-NGQDs) were studied. It was found that complex 3 had higher ϕ Δ of 0.56 compared to complex 2 with ϕ Δ of 0.24, and respective composites: 3 -FA-NGQDs had higher ϕ Δ compared to 2 -FA-NGQDs. The PDT studies were conducted for nanoparticles (FA-NGQDs), complexes (2, 3), and respective composites (2 -FA-NGQDs, and 3 -FA-NGQDs) using MCF-7 breast cancer cell. Dark toxicity of all compounds was above 90% which is negligible. At a highest concentration of 40 µg/mL, 3 -FA-NGQDs gave the lowest cell viability of 28% compared to all other conjugates and porphyrins alone. [ABSTRACT FROM AUTHOR]

• The paper describes the synthesis and photophysicochemical parameters of novel cationic chalcone-derived tetrasubstituted zn (II) and in (III) phthalocyanines used for fast removal of multidrug-resistant bacterial planktonic cells, biofilms and eradication of MCF-7 cancer cells through photodynamic processes. Chalcone possess intrinsic anticancer and antibacterial properties, on top of that positive charges allow the drugs to easily bind to the target cells and improve solubility thus resulted in effective photodynamic antimicrobial therapy (PACT) activity against S. aureus and E. coli planktonic cells as well as their most stubborn biofilms, with the highest log reduction ever report for metallophthalocyanines. A high photoactive effect of these photosensitisers was also observed when testes on MCF-7 breast cancer cell line. New tetrasubstituted zinc (II) and indium (III) phthalocyanines bearing dimethylamino chalcone group (complexes 3 and 4) as well as their quaternized analogs (3a and 4a) have been assessed for their photodynamic therapy (PDT) of cancer as well as photodynamic antimicrobial chemotherapy activities against biofilms and planktonic cultures of pathogenic bacteria of Staphylococcus aureus and Escherichia coli. Compared to the non-quaternized phthalocyanines 3 and 4 , the cationic phthalocyanines 3a and 4a exhibit a higher photodynamic inactivation against the planktonic cells with log reduction values above 9 at a concentration of 1.25 µM. This was attributed to the positive charge which enhances cellular uptake. More interestingly, 3a and 4a show a higher photodynamic inactivation (less than 3% of S. aureus survived) on their biofilm counterparts thanks to their stronger affinity to these cells. 3a and 4a Pcs also exhibited interesting PDT activity against MCF-7 cancer cells giving IC 50 values of 17.9 and 7.4 μM, respectively following 15 min irradiation. The obtained results in this work show that the positively charged phthalocyanines 3a and 4a are potential antibacterial photosensitizers that show some selectivity toward the Gram-positive and Gram-negative bacteria as well as MCF-7 breasts cancer cells. [ABSTRACT FROM AUTHOR]

• Photodynamic antimicrobial chemotherapy (PACT) activities of cationic and neutral phthalocyanines (Pcs) are evaluated against S. aureus, E. coli and C. albicans. • Cationic phthalocyanine showed high efficacy values of >7 log reduction value for all microorganisms. • The Pcs are covalently linked to modified polyacrylonitrile (PAN) and to PAN conjugated to chitosan. • Excellent bacterial colony reduction of >90% against both S. aureus and C. albicans in the presence of chitosan. The work is based on the synthesis and photodynamic antimicrobial chemotherapy (PACT) activities of neutral (1 and 2) and cationic (1Q and 2Q) morpholine substituted phthalocyanines. For applicability, these complexes were covalently linked to modified polyacrylonitrile (PAN) to form 1-PAN, 2-PAN, 1Q-PAN , and 2Q-PAN , respectively. Chitosan was conjugated to PAN (to form PAN-CS) which was then linked to the Pcs to form PAN-CS-1, PAN-CS-2, PAN-CS-1Q, and PAN-CS-2Q , respectively. Singlet oxygen quantum yields improved following the inclusion of chitosan. The PACT activities of the complexes alone and when anchored to both PAN and PAN-CS was evaluated against bacteria: S. aureus, E. coli and fungi C. albicans. Cationic phthalocyanine showed high efficacy values of >7 log reduction value for all microorganisms. These results translated into excellent bacterial colony reduction of >90% against both S. aureus and C. albicans after 1 h of photoirradiation on PAN-CS support. [Display omitted] [ABSTRACT FROM AUTHOR]

• Asymmetrically substituted neutral or charged in and Zn phthalocyanines (Pcs) are linked to B doped detonation nanodiamonds (DNDs). • The highest triplet and singlet oxygen quantum yields were observed for cationic and asymmetrically substituted. • The presence of B@DNDs, asymmetry and positive charge on the Pc resulted in improved photodynamic therapy activity. The synthesis, photophysicochemical and photodynamic therapy (PDT) activities of benzothiazole substituted zinc phthalocyanine (Pc): 1 (asymmetrically substituted and composed of no charges), 2 (asymmetrically substituted and composed of three positive charges), and 3 (symmetrically substituted and composed of four positive charges), are presented. The triplet and singlet oxygen quantum yields were highest for complex 2 showing the importance of asymmetry and charge. The complexes are covalently and non-covalently linked to B doped detonation nanodiamonds (B@DNDs) to yield nanohybrids (B@DNDs- 1 , B@DNDs- 2, B@DNDs- 3). The presence of B@DNDs, asymmetry and positive charge resulted in improved PDT with the lowest cell viability being observed for B@DNDs- 2 at 5%. The cell viability ranged from 5% to 7% for the nanohybrids compared to 19–26% for Pcs alone. [Display omitted] [ABSTRACT FROM AUTHOR]

• Cationic morpholino-substituted phthalocyanine (Pc) is conjugated to graphene quantum dots (GQDs) to generate reactive oxygen species. • The conjugate is used for photodynamic therapy (PDT), sonodynamic therapy (SDT) and the combination of both in photo-sonodynamic therapy (PSDT). • The involvement of both the 1O 2 and •OH radicals was evident after SDT and PSDT treatments. • The Pc alone showed better activity compared to the GQDs and the conjugates as evidenced by better anticancer activity and lower IC50 value. In this work, we explore the reactive oxygen species (ROS) generation abilities of cationic morpholino-substituted-phthalocyanine (Pc) conjugated to nitrogen (NGQDs) and nitrogen-sulfur (NSGQDs) doped-graphene quantum dots upon irradiation with light for photodynamic therapy (PDT), ultrasound for sonodynamic therapy (SDT) and the combination of both in photo-sonodynamic therapy (PSDT). The in vitro cytotoxicity studies were conducted using the Michigan Cancer Foundation-7 breast cancer cell lines (MCF-7 cells). For PDT treatments, only the 1O 2 was detected for all the sensitizers, whereas both the 1O 2 and •OH radicals were evident after SDT and PSDT treatments. An increase in the 1O 2 generation was observed for the conjugates compared to the GQDs and the Pc alone. However, the •OH radicals were reduced in the conjugates compared to the GQDs and the Pc alone. The NGQDs generally showed better ROS generation efficacy compared to the NSGQDs, alone and in the conjugates. The combination therapy also shows improved efficacy compared to the monotherapies for the Pcs and Pc-GQDs conjugates. [ABSTRACT FROM AUTHOR]

• Hybrid material of MnO 2 @PtNPs (NPs = nanoparticles), graphene quantum dots (GQDs) and zinc phthalocyanine (ZnPc) is presented. • The hybrid material was encapsulated into liposomes affording it enhanced water solubility. • ZnPc-GQDs-MnO 2 @PtNPs-liposome was linked to folic acid. • The conjugate showed excellent activity for tumour treatment in hypoxic conditions through photodynamic therapy. The hypoxic tumour microenvironment and poor spatiotemporal localization of photosensitizers are two significant obstacles that limit practical applications of photodynamic therapy. In response, a biocompatible, light-activatable liposome integrated with both a zinc phthalocyanine photodynamic component and Pt nanoparticles-decorated with MnO 2 catalase-mimicking component are engineered. This multifunctional system was rationally designed using unsaturated phospholipids to achieve on-demand drug release following light irradiation. Specificity was achieved by folic acid functionalization resulting in folate-modified liposomes (FTLiposomes). We demonstrated its specific uptake by fluorescence imaging using folate receptor (FR) overexpressing HeLa and MCF-7 cells as in vitro models. This multifunctional liposome exhibits superior hypoxic anti-tumour effects and holds the potential to reduce side effects associated with untargeted therapy. Fluorescence of the constituent ZnPc and folate-receptor targeting could enable tracking and permit spatiotemporal regulation for improved cancer treatment. [Display omitted] [ABSTRACT FROM AUTHOR]