Folic acid-modified phthalocyanine-nanozyme loaded liposomes for targeted photodynamic therapy
- Nwahara, Nnamdi, Abrahams, Garth, Prinsloo, Earl, Nyokong, Tebello
- Authors: Nwahara, Nnamdi , Abrahams, Garth , Prinsloo, Earl , Nyokong, Tebello
- Date: 2021
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/231369 , vital:49881 , xlink:href="https://doi.org/10.1016/j.pdpdt.2021.102527"
- Description: 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 MnO2 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.
- Full Text:
- Date Issued: 2021
- Authors: Nwahara, Nnamdi , Abrahams, Garth , Prinsloo, Earl , Nyokong, Tebello
- Date: 2021
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/231369 , vital:49881 , xlink:href="https://doi.org/10.1016/j.pdpdt.2021.102527"
- Description: 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 MnO2 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.
- Full Text:
- Date Issued: 2021
Photophysicochemical properties of nanoconjugates of zinc (II) 2 (3)-mono-2-(4-oxy) phenoxy) acetic acid phthalocyanine with cysteamine capped silver and silver–gold nanoparticles
- Oluwole, David O, Prinsloo, Earl, Nyokong, Tebello
- Authors: Oluwole, David O , Prinsloo, Earl , Nyokong, Tebello
- Date: 2016
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/188552 , vital:44764 , xlink:href="https://doi.org/10.1016/j.poly.2016.09.034"
- Description: A novel asymmetrical zinc(II) 2(3)-mono-2-(4-oxy)phenoxy)acetic acid phthalocyanine (complex 1) was synthesized and subsequently linked to cysteamine capped silver (AgNPs) and silver–gold (AgAuNPs) nanoparticles (NPs) via amide bonds. The photophysicochemical properties and in vitro photodynamic therapy activity of complex 1 and its nanoconjugates were investigated. The nanoconjugates showed improved photophysical properties compared to complex 1 alone. The fluorescence, triplet and singlet quantum yields of complex 1 were found to be 20%, 48%, and 43% respectively. Complex 1 showed in vitro dark cytotoxicity, but the dark toxicity was reduced for the combination of complex 1 with AgAuNPs, this combination also gave the best photodynamic therapy activity when compared to complex 1 and its conjugate with AgNPs without AuNPs.
- Full Text:
- Date Issued: 2016
- Authors: Oluwole, David O , Prinsloo, Earl , Nyokong, Tebello
- Date: 2016
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/188552 , vital:44764 , xlink:href="https://doi.org/10.1016/j.poly.2016.09.034"
- Description: A novel asymmetrical zinc(II) 2(3)-mono-2-(4-oxy)phenoxy)acetic acid phthalocyanine (complex 1) was synthesized and subsequently linked to cysteamine capped silver (AgNPs) and silver–gold (AgAuNPs) nanoparticles (NPs) via amide bonds. The photophysicochemical properties and in vitro photodynamic therapy activity of complex 1 and its nanoconjugates were investigated. The nanoconjugates showed improved photophysical properties compared to complex 1 alone. The fluorescence, triplet and singlet quantum yields of complex 1 were found to be 20%, 48%, and 43% respectively. Complex 1 showed in vitro dark cytotoxicity, but the dark toxicity was reduced for the combination of complex 1 with AgAuNPs, this combination also gave the best photodynamic therapy activity when compared to complex 1 and its conjugate with AgNPs without AuNPs.
- Full Text:
- Date Issued: 2016
The effects of silica based nanoparticles on the photophysicochemical properties, in vitro dark viability and photodynamic therapy study of zinc monocarboxyphenoxy phthalocyanine
- Oluwole, David O, Uddin, Imran, Prinsloo, Earl, Nyokong, Tebello
- Authors: Oluwole, David O , Uddin, Imran , Prinsloo, Earl , Nyokong, Tebello
- Date: 2016
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/240371 , vital:50828 , xlink:href="https://doi.org/10.1016/j.jphotochem.2016.07.002"
- Description: Aminopropyl triethoxysilane functionalized core SiO2 and core/shell ZnO/SiO2 nanoparticles (NP) were covalently linked to zinc monocarboxyphenoxy phthalocyanine (ZnMCPPc, complex 1) via amide bond formation. The photophysicochemical behavior, in vitro dark viability and photodynamic therapy (PDT) activity against human breast adenocarcinoma cell line (MCF-7 cells) of the conjugates were studied. The nanoconjugates showed enhanced photophysicochemical behavior as compared to complex 1 alone. Complex 1 showed higher dark toxicity against MCF-7 cells when compared to the conjugates. In the dark, complex 1 accounted for less than 50% viable cells at 28.6 μg/mL and 57.1 μg/mL compared to the conjugates which accounted for more than 50% cell viability at these concentrations. The in vitro dark viability and PDT activity of complex 1 was reduced in the presence of these nanoparticles.
- Full Text:
- Date Issued: 2016
- Authors: Oluwole, David O , Uddin, Imran , Prinsloo, Earl , Nyokong, Tebello
- Date: 2016
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/240371 , vital:50828 , xlink:href="https://doi.org/10.1016/j.jphotochem.2016.07.002"
- Description: Aminopropyl triethoxysilane functionalized core SiO2 and core/shell ZnO/SiO2 nanoparticles (NP) were covalently linked to zinc monocarboxyphenoxy phthalocyanine (ZnMCPPc, complex 1) via amide bond formation. The photophysicochemical behavior, in vitro dark viability and photodynamic therapy (PDT) activity against human breast adenocarcinoma cell line (MCF-7 cells) of the conjugates were studied. The nanoconjugates showed enhanced photophysicochemical behavior as compared to complex 1 alone. Complex 1 showed higher dark toxicity against MCF-7 cells when compared to the conjugates. In the dark, complex 1 accounted for less than 50% viable cells at 28.6 μg/mL and 57.1 μg/mL compared to the conjugates which accounted for more than 50% cell viability at these concentrations. The in vitro dark viability and PDT activity of complex 1 was reduced in the presence of these nanoparticles.
- Full Text:
- Date Issued: 2016
Photophysical properties and photodynamic therapy effect of zinc phthalocyanine-spermine-single walled carbon nanotube conjugate on MCF-7 breast cancer cell line
- Ogbodu, Rachael O, Limson, Janice L, Prinsloo, Earl, Nyokong, Tebello
- Authors: Ogbodu, Rachael O , Limson, Janice L , Prinsloo, Earl , Nyokong, Tebello
- Date: 2015
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/189493 , vital:44851 , xlink:href="https://doi.org/10.1016/j.synthmet.2015.03.011"
- Description: The present study shows improved photodynamic therapy (PDT) effect of zinc mono carboxy phenoxy phthalocyanine (ZnMCPPc (1)) upon conjugation to spermine (via amide bond) as a targeting molecule on MCF-7 breast cancer cells. The ZnMCPPc-spermine (2) conjugate was adsorbed onto single walled carbon nanotubes (represented as ZnMCPPc-spermine-SWCNT (3)). There was no change in the fluorescence quantum yield of complex 1 following formation of 2 or 3. Complexes 2 and 3 showed improved photophysical properties; with over 50% increases in triplet and singlet oxygen quantum yields compared to 1. Complexes 1, 2 and 3 were relatively not toxic to MCF-7 cancer cells when incubated with 5–40 μM of each complex for 24 h in the dark. The PDT results showed that at 40 μM complex 1 resulted in only 64% decrease in cell viability, while 2 and 3 improved the PDT effect of 1 to 97% and 95% decrease in cell viability at 40 μM respectively.
- Full Text:
- Date Issued: 2015
- Authors: Ogbodu, Rachael O , Limson, Janice L , Prinsloo, Earl , Nyokong, Tebello
- Date: 2015
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/189493 , vital:44851 , xlink:href="https://doi.org/10.1016/j.synthmet.2015.03.011"
- Description: The present study shows improved photodynamic therapy (PDT) effect of zinc mono carboxy phenoxy phthalocyanine (ZnMCPPc (1)) upon conjugation to spermine (via amide bond) as a targeting molecule on MCF-7 breast cancer cells. The ZnMCPPc-spermine (2) conjugate was adsorbed onto single walled carbon nanotubes (represented as ZnMCPPc-spermine-SWCNT (3)). There was no change in the fluorescence quantum yield of complex 1 following formation of 2 or 3. Complexes 2 and 3 showed improved photophysical properties; with over 50% increases in triplet and singlet oxygen quantum yields compared to 1. Complexes 1, 2 and 3 were relatively not toxic to MCF-7 cancer cells when incubated with 5–40 μM of each complex for 24 h in the dark. The PDT results showed that at 40 μM complex 1 resulted in only 64% decrease in cell viability, while 2 and 3 improved the PDT effect of 1 to 97% and 95% decrease in cell viability at 40 μM respectively.
- Full Text:
- Date Issued: 2015
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