Advances in Natural Sciences: Nanoscience and Nanotechnology
Green nanotechnology produces biocompatible gold nanoparticles (AuNPs) with intrinsic anti-microb... more Green nanotechnology produces biocompatible gold nanoparticles (AuNPs) with intrinsic anti-microbial, anti-viral, and anti-tumour properties. Green AuNPs (g-AuNPs) are gaining a solid ground in prostate cancer (PC) nanotherapy. Hence, in this review, we summarise and compare data from studies published between 2015 and 2022 to highlight major biological compounds and outputs from in vitro and in vivo applications of green or biosynthesised AuNPs in PC theranostics. In fact, g-AuNPs can be easily generated with effective antiproliferative PC characteristics. Taken together, g-AuNPs exert various apoptosis-related mechanisms, such as reactive oxygen species (ROS) generation, cell cycle arrest, cytotoxicity, mitochondrial disruption, and anti-tumour immune cell activation, with additional successful delivery of the biological compounds in green materials. g-AuNPs could offer another modality for targeted cancer therapy using antibodies and targeting ligands to specifically recognise an...
Single chain variable D2B antibody fragments (scFvD2Bs) exhibit high affinity binding to prostate... more Single chain variable D2B antibody fragments (scFvD2Bs) exhibit high affinity binding to prostate specific membrane antigens overexpressed in metastatic prostate cancer (PC). Conjugation of scFvD2B to gold nanoparticles (AuNPs) would enhance its stability and plasma half-life circulation to shuttle theranostic agents in PC. In this study, we synthesized PEGylated scFvD2B-AuNPs (AuNPs-scFvD2B-PEG) and tested their integrity, biocompatibility, and immunogenicity in freshly withdrawn human blood. Prior to blood incubation, Zeta potential measurements, UV-Vis spectroscopy, and dynamic light scattering (DLS) were used to assess the physicochemical properties of our nano-complexes in the presence or absence of PEGylation. A surface plasmon resonance band shift of 2 and 4 nm confirmed the successful coating for AuNPs-scFvD2B and AuNPs-scFvD2B-PEG, respectively. Likewise, DLS revealed a size increase of ~3 nm for AuNPs-scFvD2B and ~19 nm for AuNPs-scFvD2B-PEG. Zeta potential increased from ...
The use of quartz crystal microbalance with dissipation (QCM-D) for studying nanoparticle-induced... more The use of quartz crystal microbalance with dissipation (QCM-D) for studying nanoparticle-induced platelet aggregation
The potential of RNA interference (RNAi)-based therapeutics for cancer has received much attentio... more The potential of RNA interference (RNAi)-based therapeutics for cancer has received much attention; however, delivery of RNAi effectors, such as small interfering RNA (siRNA), remains an obstacle to clinical translation. Non-viral delivery vectors have been used extensively to enhance siRNA delivery. Recently, the potential of gold nanoparticles (AuNPs) for transporting drugs, proteins and genetic materials has been demonstrated. Previously, our laboratory synthesised positively charged, surfactant-free AuNPs in water by the reduction of gold (III) chloride (AuCl3) using hydroxylamine hydrochloride (NH2OH·HCl) in the presence of L-cysteine methyl ester hydrochloride (HSCH2CH(NH2)COOCH3·HCl) as a capping agent. These AuNPs, which achieve higher cell viability in comparison to cetyl trimethyl ammonium bromide (CTAB, a surfactant)-capped counterparts, have demonstrated potential for siRNA delivery. However, it is well known that systemic administration of cationic delivery systems with...
Interactions between blood platelets and nanoparticles have both pharmacological and toxicologica... more Interactions between blood platelets and nanoparticles have both pharmacological and toxicological significance and may lead to platelet activation and aggregation. Platelet aggregation is usually studied using light aggregometer that neither mimics the conditions found in human microvasculature nor detects microaggregates. A new method for the measurement of platelet microaggregation under flow conditions using a commercially available quartz crystal microbalance with dissipation (QCM-D) has recently been developed. The aim of the current study was to investigate if QCM-D could be used for the measurement of nanoparticle-platelet interactions. Silica, polystyrene, and gold nanoparticles were tested. The interactions were also studied using light aggregometry and flow cytometry, which measured surface abundance of platelet receptors. Platelet activation was imaged using phase contrast and scanning helium ion microscopy. QCM-D was able to measure nanoparticle-induced platelet microag...
The increasing use of gold nanoparticles in medical diagnosis and treatment has raised the concer... more The increasing use of gold nanoparticles in medical diagnosis and treatment has raised the concern over their blood compatibility. The interactions of nanoparticles with blood components may lead to platelet aggregation and endothelial dysfunction. Therefore, medical applications of gold nanoparticles call for increased nanoparticle stability and biocompatibility. Functionalisation of nanoparticles with polythelene glycol (PEGylation) is known to modulate cell-particle interactions. Therefore, the aim of the current study was to investigate the effects of PEGylated-gold nanoparticles on human platelet function and endothelial cells in vitro. Gold nanoparticles, 15 nm in diameter, were synthesised in water using sodium citrate as a reducing and stabilising agent. Functionalised polyethylene glycol-based thiol polymers were used to coat and stabilise pre-synthesised gold nanoparticles. The interaction of gold nanoparticles-citrate and PEGylated-gold nanoparticles with human platelets was measured by Quartz Crystal Microbalance with Dissipation. Platelet-nanoparticles interaction was imaged using phase-contrast, scanning and transmission electron microscopy. The inflammatory effects of gold nanoparticles-citrate and PEGylated-gold nanoparticles in endothelial cells were measured by quantitative real time polymerase chain reaction. PEGylated-gold nanoparticles were stable under physiological conditions and PEGylated-gold nanoparticles-5400 and PEGylated-gold nanoparticles-10800 did not affect platelet aggregation as measured by Quartz Crystal Microbalance with Dissipation. In addition, PEGylated-gold nanoparticles did not induce an inflammatory response when incubated with endothelial cells. Therefore, this study shows that PEGylated-gold nanoparticles with a higher molecular weight of the polymer chain are both platelet- and endothelium-compatible making them attractive candidates for biomedical applications.
Tin selenide (SnSe), a highly promising layered material, has been garnering particular interest ... more Tin selenide (SnSe), a highly promising layered material, has been garnering particular interest in recent times due to its significant promise for future energy devices. Herein we report a simple solution phase approach for growing highly crystalline layered SnSe nanoribbons. Polyvinylpyrrolidone (PVP) was used as a templating agent to selectively passivates the (100) and (001) facets of the SnSe nanoribbons resulting in the unique growth of nanoribbons along their b-axis with a defined zigzag edge state along the sidewalls. The SnSe nanoribbons are few layers thick (~ 20 layers), with mean widths of ~40 nm, and achievable length of > 1 m. Nanoribbons could be produced in relatively high quantities (>150 mg) in a single batch experiment. The PVP coating also offer some resistance to oxidation, with removal of the PVP seen to lead to the formation a SnSe/SnOx core shell structure. The use of non-toxic PVP to replace toxic amines that are typically employed for other 1D forms ...
In this study Silver (Ag) and Gold (Au) nanoparticles (NPs) of different surface charges (positiv... more In this study Silver (Ag) and Gold (Au) nanoparticles (NPs) of different surface charges (positively charged, negatively charged, or nearly neutral) and sizes were obtained using ascorbic acid as a reducing agent and multiple polymers such as Chitosan (Chit), Poly-L-Lysine (PLL), Polyvinyl alcohol (PVA), Polyethylene glycol (PEG) or sodium citrate as stabilizing ligands. The obtained NPs were characterized using UV-visible spectroscopy (UV-vis), Dynamic Light Scattering (DLS), and Zeta Potential (ζ) measurements. On the other hand, AuNPs with different coating (PLL, PVA and PEG) and charges were tested on whole human blood samples, specifically on neutrophils using a Neutrophil Function Test (NFT). Our results demonstrated that AuNPs-PVA with a slight negative charge (ζ = -15 mV) and PEgylated AuNPs-PLL (AuNPs-PLL-PEG) with a slight positive charge (ζ = + 9 mV) were found to be the least detected by neutrophils making them suitable for biomedical applications.
Dans ce travail on a developpe une nouvelle strategie de stabilisation de nanoparticules dans l&#... more Dans ce travail on a developpe une nouvelle strategie de stabilisation de nanoparticules dans l'eau. Cette strategie se base sur l'utilisation de copolymeres amphiphiles, capables de s'auto-organiser autour des nanoparticules. Comme modele on a choisi des copolymeres a blocs (diblocs et triblocs) a base de poly(oxyethylene) et de poly(oxypropylene). La stabilisation de nanoparticules d'or a pu etre etudiee grâce a leurs proprietes optiques. On a demontre que la presence et la longueur de la chaine hydrophobe sont essentielles pour la stabilisation. Ensuite, differentes techniques d'analyse (DDL, MET, SANS, Cryo-MET. . . ) ont permis de montrer que les copolymeres s'adsorbent a la surface des nanoparticules, meme en l'absence de micelle en solution (C<CMC). Enfin, nous demontrons la faible cytotoxicite des nanoparticules stabilisees par ces polymeres. Mots cles : stabilisation dans l'eau, polymeres a blocs, nanoparticules d'or, resonnance plasmo...
Advances in Natural Sciences: Nanoscience and Nanotechnology
Green nanotechnology produces biocompatible gold nanoparticles (AuNPs) with intrinsic anti-microb... more Green nanotechnology produces biocompatible gold nanoparticles (AuNPs) with intrinsic anti-microbial, anti-viral, and anti-tumour properties. Green AuNPs (g-AuNPs) are gaining a solid ground in prostate cancer (PC) nanotherapy. Hence, in this review, we summarise and compare data from studies published between 2015 and 2022 to highlight major biological compounds and outputs from in vitro and in vivo applications of green or biosynthesised AuNPs in PC theranostics. In fact, g-AuNPs can be easily generated with effective antiproliferative PC characteristics. Taken together, g-AuNPs exert various apoptosis-related mechanisms, such as reactive oxygen species (ROS) generation, cell cycle arrest, cytotoxicity, mitochondrial disruption, and anti-tumour immune cell activation, with additional successful delivery of the biological compounds in green materials. g-AuNPs could offer another modality for targeted cancer therapy using antibodies and targeting ligands to specifically recognise an...
Single chain variable D2B antibody fragments (scFvD2Bs) exhibit high affinity binding to prostate... more Single chain variable D2B antibody fragments (scFvD2Bs) exhibit high affinity binding to prostate specific membrane antigens overexpressed in metastatic prostate cancer (PC). Conjugation of scFvD2B to gold nanoparticles (AuNPs) would enhance its stability and plasma half-life circulation to shuttle theranostic agents in PC. In this study, we synthesized PEGylated scFvD2B-AuNPs (AuNPs-scFvD2B-PEG) and tested their integrity, biocompatibility, and immunogenicity in freshly withdrawn human blood. Prior to blood incubation, Zeta potential measurements, UV-Vis spectroscopy, and dynamic light scattering (DLS) were used to assess the physicochemical properties of our nano-complexes in the presence or absence of PEGylation. A surface plasmon resonance band shift of 2 and 4 nm confirmed the successful coating for AuNPs-scFvD2B and AuNPs-scFvD2B-PEG, respectively. Likewise, DLS revealed a size increase of ~3 nm for AuNPs-scFvD2B and ~19 nm for AuNPs-scFvD2B-PEG. Zeta potential increased from ...
The use of quartz crystal microbalance with dissipation (QCM-D) for studying nanoparticle-induced... more The use of quartz crystal microbalance with dissipation (QCM-D) for studying nanoparticle-induced platelet aggregation
The potential of RNA interference (RNAi)-based therapeutics for cancer has received much attentio... more The potential of RNA interference (RNAi)-based therapeutics for cancer has received much attention; however, delivery of RNAi effectors, such as small interfering RNA (siRNA), remains an obstacle to clinical translation. Non-viral delivery vectors have been used extensively to enhance siRNA delivery. Recently, the potential of gold nanoparticles (AuNPs) for transporting drugs, proteins and genetic materials has been demonstrated. Previously, our laboratory synthesised positively charged, surfactant-free AuNPs in water by the reduction of gold (III) chloride (AuCl3) using hydroxylamine hydrochloride (NH2OH·HCl) in the presence of L-cysteine methyl ester hydrochloride (HSCH2CH(NH2)COOCH3·HCl) as a capping agent. These AuNPs, which achieve higher cell viability in comparison to cetyl trimethyl ammonium bromide (CTAB, a surfactant)-capped counterparts, have demonstrated potential for siRNA delivery. However, it is well known that systemic administration of cationic delivery systems with...
Interactions between blood platelets and nanoparticles have both pharmacological and toxicologica... more Interactions between blood platelets and nanoparticles have both pharmacological and toxicological significance and may lead to platelet activation and aggregation. Platelet aggregation is usually studied using light aggregometer that neither mimics the conditions found in human microvasculature nor detects microaggregates. A new method for the measurement of platelet microaggregation under flow conditions using a commercially available quartz crystal microbalance with dissipation (QCM-D) has recently been developed. The aim of the current study was to investigate if QCM-D could be used for the measurement of nanoparticle-platelet interactions. Silica, polystyrene, and gold nanoparticles were tested. The interactions were also studied using light aggregometry and flow cytometry, which measured surface abundance of platelet receptors. Platelet activation was imaged using phase contrast and scanning helium ion microscopy. QCM-D was able to measure nanoparticle-induced platelet microag...
The increasing use of gold nanoparticles in medical diagnosis and treatment has raised the concer... more The increasing use of gold nanoparticles in medical diagnosis and treatment has raised the concern over their blood compatibility. The interactions of nanoparticles with blood components may lead to platelet aggregation and endothelial dysfunction. Therefore, medical applications of gold nanoparticles call for increased nanoparticle stability and biocompatibility. Functionalisation of nanoparticles with polythelene glycol (PEGylation) is known to modulate cell-particle interactions. Therefore, the aim of the current study was to investigate the effects of PEGylated-gold nanoparticles on human platelet function and endothelial cells in vitro. Gold nanoparticles, 15 nm in diameter, were synthesised in water using sodium citrate as a reducing and stabilising agent. Functionalised polyethylene glycol-based thiol polymers were used to coat and stabilise pre-synthesised gold nanoparticles. The interaction of gold nanoparticles-citrate and PEGylated-gold nanoparticles with human platelets was measured by Quartz Crystal Microbalance with Dissipation. Platelet-nanoparticles interaction was imaged using phase-contrast, scanning and transmission electron microscopy. The inflammatory effects of gold nanoparticles-citrate and PEGylated-gold nanoparticles in endothelial cells were measured by quantitative real time polymerase chain reaction. PEGylated-gold nanoparticles were stable under physiological conditions and PEGylated-gold nanoparticles-5400 and PEGylated-gold nanoparticles-10800 did not affect platelet aggregation as measured by Quartz Crystal Microbalance with Dissipation. In addition, PEGylated-gold nanoparticles did not induce an inflammatory response when incubated with endothelial cells. Therefore, this study shows that PEGylated-gold nanoparticles with a higher molecular weight of the polymer chain are both platelet- and endothelium-compatible making them attractive candidates for biomedical applications.
Tin selenide (SnSe), a highly promising layered material, has been garnering particular interest ... more Tin selenide (SnSe), a highly promising layered material, has been garnering particular interest in recent times due to its significant promise for future energy devices. Herein we report a simple solution phase approach for growing highly crystalline layered SnSe nanoribbons. Polyvinylpyrrolidone (PVP) was used as a templating agent to selectively passivates the (100) and (001) facets of the SnSe nanoribbons resulting in the unique growth of nanoribbons along their b-axis with a defined zigzag edge state along the sidewalls. The SnSe nanoribbons are few layers thick (~ 20 layers), with mean widths of ~40 nm, and achievable length of > 1 m. Nanoribbons could be produced in relatively high quantities (>150 mg) in a single batch experiment. The PVP coating also offer some resistance to oxidation, with removal of the PVP seen to lead to the formation a SnSe/SnOx core shell structure. The use of non-toxic PVP to replace toxic amines that are typically employed for other 1D forms ...
In this study Silver (Ag) and Gold (Au) nanoparticles (NPs) of different surface charges (positiv... more In this study Silver (Ag) and Gold (Au) nanoparticles (NPs) of different surface charges (positively charged, negatively charged, or nearly neutral) and sizes were obtained using ascorbic acid as a reducing agent and multiple polymers such as Chitosan (Chit), Poly-L-Lysine (PLL), Polyvinyl alcohol (PVA), Polyethylene glycol (PEG) or sodium citrate as stabilizing ligands. The obtained NPs were characterized using UV-visible spectroscopy (UV-vis), Dynamic Light Scattering (DLS), and Zeta Potential (ζ) measurements. On the other hand, AuNPs with different coating (PLL, PVA and PEG) and charges were tested on whole human blood samples, specifically on neutrophils using a Neutrophil Function Test (NFT). Our results demonstrated that AuNPs-PVA with a slight negative charge (ζ = -15 mV) and PEgylated AuNPs-PLL (AuNPs-PLL-PEG) with a slight positive charge (ζ = + 9 mV) were found to be the least detected by neutrophils making them suitable for biomedical applications.
Dans ce travail on a developpe une nouvelle strategie de stabilisation de nanoparticules dans l&#... more Dans ce travail on a developpe une nouvelle strategie de stabilisation de nanoparticules dans l'eau. Cette strategie se base sur l'utilisation de copolymeres amphiphiles, capables de s'auto-organiser autour des nanoparticules. Comme modele on a choisi des copolymeres a blocs (diblocs et triblocs) a base de poly(oxyethylene) et de poly(oxypropylene). La stabilisation de nanoparticules d'or a pu etre etudiee grâce a leurs proprietes optiques. On a demontre que la presence et la longueur de la chaine hydrophobe sont essentielles pour la stabilisation. Ensuite, differentes techniques d'analyse (DDL, MET, SANS, Cryo-MET. . . ) ont permis de montrer que les copolymeres s'adsorbent a la surface des nanoparticules, meme en l'absence de micelle en solution (C<CMC). Enfin, nous demontrons la faible cytotoxicite des nanoparticules stabilisees par ces polymeres. Mots cles : stabilisation dans l'eau, polymeres a blocs, nanoparticules d'or, resonnance plasmo...
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Papers by Kamil Rahme