In vitro dual-modality chemo-photodynamic therapy via stimuli-triggered polymeric micelles

2016 ◽  
Vol 98 ◽  
pp. 56-64 ◽  
Author(s):  
Ching-Yi Chen ◽  
Yun-Chu Wang ◽  
Chi-Chiuan Hung
2021 ◽  
Vol 11 (2) ◽  
pp. 136
Author(s):  
Shanghui Gao ◽  
Rayhanul Islam ◽  
Jun Fang

Targeted tumor accumulation, tumor environment responsive drug release, and effective internalization are critical issues being considered in developing anticancer nanomedicine. In this context, we synthesized a tumor environment-responsive nanoprobe for anticancer photodynamic therapy (PDT) that is a hyaluronan conjugated zinc protoporphyrin via an ester bond (HA-es-ZnPP), and we examined its anticancer PDT effect both in vitro and in vivo. HA-es-ZnPP exhibits high water-solubility and forms micelles of ~40 nm in aqueous solutions. HA-es-ZnPP shows fluorescence quenching without apparent 1O2 generation under light irradiation because of micelle formation. However, 1O2 was extensively generated when the micelle is disrupted, and ZnPP is released. Compared to native ZnPP, HA-es-ZnPP showed lower but comparable intracellular uptake and cytotoxicity in cultured mouse C26 colon cancer cells; more importantly, light irradiation resulted in 10-time increased cytotoxicity, which is the PDT effect. In a mouse sarcoma S180 solid tumor model, HA-es-ZnPP as polymeric micelles exhibited a prolonged systemic circulation time and the consequent tumor-selective accumulation based on the enhanced permeability and retention (EPR) effect was evidenced. Consequently, a remarkable anticancer PDT effect was achieved using HA-es-ZnPP and a xenon light source, without apparent side effects. These findings suggest the potential of HA-es-ZnPP as a candidate anticancer nanomedicine for PDT.


Author(s):  
R S Thakur ◽  
A Nayaz ◽  
Y Koushik

In the case of solubility limited absorption, creating supersaturation in the GI fluid is very critical as supersaturation may provide great improvement of oral absorption. The techniques to create the so-called supersaturation in the GI fluid include microemulsions, emulsions, liposomes, complexations, polymeric micelles, and conventional micelles. Ciprofloxacin was chosen because it is practically insoluble in water; hence its salt form is used commercially, which is soluble in water. The objective of the present investigation was to enhance the solubility of Ciprofloxacin by formulating it into microemulsion system. For this purpose, initially, surfactant and cosurfactant were selected based on their HLB value, followed by pseudo-ternary phase diagrams to identify the microemulsion existing zone. Different formulations were developed and evaluated for pH, conductivity, in vitro release and stability. Solubility study was performed for optimized formulation. The pH of the designed formulations varied from 6.02-7.04. This was ideal and near blood pH 7.4. Conductivity data indicated that the microemulsion was of the o/w type. In vitro release of optimized formulation(FM3) was 95.2% as compared to pure drug 46.61% after 90 min and marketed product(salt form) 93.9%. Hence, by formulating into microemulsion, the solubility of ciprofloxacin is significantly enhanced.    


Antibiotics ◽  
2021 ◽  
Vol 10 (7) ◽  
pp. 869
Author(s):  
Beatriz Müller Nunes Souza ◽  
Juliana Guerra Pinto ◽  
André Henrique Correia Pereira ◽  
Alejandro Guillermo Miñán ◽  
Juliana Ferreira-Strixino

Staphylococccus aureus is a ubiquitous and opportunistic bacteria associated with high mortality rates. Antimicrobial photodynamic therapy (aPDT) is based on the application of a light source and a photosensitizer that can interact with molecular oxygen, forming Reactive Oxygen Species (ROS) that result in bacterial inactivation. This study aimed to analyze, in vitro, the action of aPDT with Photodithazine® (PDZ) in methicillin-sensitive Staphylococcus aureus (MSSA) and methicillin-resistant Staphylococcus aureus (MRSA) strains. The strains were incubated with PDZ at 25, 50, 75, and 100 mg/L for 15 min and irradiated with fluences of 25, 50, and 100 J/cm2. The internalization of PDZ was evaluated by confocal microscopy, the bacterial growth by counting the number of colony-forming units, as well as the bacterial metabolic activity post-aPDT and the production of ROS. In both strains, the photosensitizer was internalized; the production of ROS increased when the aPDT was applied; there was a bacterial reduction compared to the control at all the evaluated fluences and concentrations; and, in most parameters, it was obtained complete inactivation with significant difference (p < 0.05). The implementation of aPDT with PDZ in clinical strains of S. aureus has resulted in its complete inactivation, including the MRSA strains.


2021 ◽  
Vol 14 (7) ◽  
pp. 603
Author(s):  
Vanesa Pérez-Laguna ◽  
Isabel García-Luque ◽  
Sofía Ballesta ◽  
Antonio Rezusta ◽  
Yolanda Gilaberte

The present review covers combination approaches of antimicrobial photodynamic therapy (aPDT) plus antibiotics or antifungals to attack bacteria and fungi in vitro (both planktonic and biofilm forms) focused on those microorganisms that cause infections in skin and soft tissues. The combination can prevent failure in the fight against these microorganisms: antimicrobial drugs can increase the susceptibility of microorganisms to aPDT and prevent the possibility of regrowth of those that were not inactivated during the irradiation; meanwhile, aPDT is effective regardless of the resistance pattern of the strain and their use does not contribute to the selection of antimicrobial resistance. Additive or synergistic antimicrobial effects in vitro are evaluated and the best combinations are presented. The use of combined treatment of aPDT with antimicrobials could help overcome the difficulty of fighting high level of resistance microorganisms and, as it is a multi-target approach, it could make the selection of resistant microorganisms more difficult.


Author(s):  
Shiqi Hu ◽  
Bin Huang ◽  
Yumei Pu ◽  
Chengwan Xia ◽  
Qian Zhang ◽  
...  

In this report, a new Thermally activated delayed fluorescent(TADF) molecule [2-(4-triphenylvinyl-phenyl)-anthraquinone (TPE-AQ)] was synthesized. This nanomaterial has satisfactory photostability. In vitro, it was indicated that these TADF nanoparticles (NPs) were...


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Maria-Argyro Karageorgou ◽  
Dimosthenis Stamopoulos

AbstractRadiolabeled magnetic nanoparticles are promising candidates as dual-modality-contrast-agents (DMCA) for diagnostic applications. The immunocompatibility of a new DMCA is a prerequisite for subsequent in vivo applications. Here, a new DMCA, namely Fe3O4 nanoparticles radiolabeled with 68Ga, is subjected to immunocompatibility tests both in vitro and in vivo. The in vitro immunocompatibility of the DMCA relied on incubation with donated human WBCs and PLTs (five healthy individuals). Optical microscopy (OM) and atomic force microscopy (AFM) were employed for the investigation of the morphological characteristics of WBCs and PLTs. A standard hematology analyzer (HA) provided information on complete blood count. The in vivo immunocompatibility of the DMCA was assessed through its biodistribution among the basic organs of the mononuclear phagocyte system in normal and immunodeficient mice (nine in each group). In addition, Magnetic Resonance Imaging (MRI) data were acquired in normal mice (three). The combined OM, AFM and HA in vitro data showed that although the DMCA promoted noticeable activation of WBCs and PLTs, neither degradation nor clustering were observed. The in vivo data showed no difference of the DMCA biodistribution between the normal and immunodeficient mice, while the MRI data prove the efficacy of the particular DMCA when compared to the non-radiolabeled, parent CA. The combined in vitro and in vivo data prove that the particular DMCA is a promising candidate for future in vivo applications.


Pharmaceutics ◽  
2021 ◽  
Vol 13 (8) ◽  
pp. 1176
Author(s):  
Vanesa Pérez-Laguna ◽  
Yolanda Barrena-López ◽  
Yolanda Gilaberte ◽  
Antonio Rezusta

Candidiasis is very common and complicated to treat in some cases due to increased resistance to antifungals. Antimicrobial photodynamic therapy (aPDT) is a promising alternative treatment. It is based on the principle that light of a specific wavelength activates a photosensitizer molecule resulting in the generation of reactive oxygen species that are able to kill pathogens. The aim here is the in vitro photoinactivation of three strains of Candida spp., Candida albicans ATCC 10231, Candida parapsilosis ATCC 22019 and Candida krusei ATCC 6258, using aPDT with different sources of irradiation and the photosensitizer methylene blue (MB), alone or in combination with chlorhexidine (CHX). Irradiation was carried out at a fluence of 18 J/cm2 with a light-emitting diode (LED) lamp emitting in red (625 nm) or a white metal halide lamp (WMH) that emits at broad-spectrum white light (420–700 nm). After the photodynamic treatment, the antimicrobial effect is evaluated by counting colony forming units (CFU). MB-aPDT produces a 6 log10 reduction in the number of CFU/100 μL of Candida spp., and the combination with CHX enhances the effect of photoinactivation (effect achieved with lower concentration of MB). Both lamps have similar efficiencies, but the WMH lamp is slightly more efficient. This work opens the doors to a possible clinical application of the combination for resistant or persistent forms of Candida infections.


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