scholarly journals Influence of Hyperthermia on Efficacy and Uptake of Carbon Nanohorn-Cisplatin Conjugates

2014 ◽  
Vol 136 (2) ◽  
Author(s):  
Matthew R. DeWitt ◽  
Allison M. Pekkanen ◽  
John Robertson ◽  
Christopher G. Rylander ◽  
Marissa Nichole Rylander
Keyword(s):  
Cellular Uptake ◽  
Near Infrared ◽  
Drug Efficacy ◽  
Infrared Light ◽  
Exterior Surface ◽  
Mild Hyperthermia ◽  
Carbon Nanohorns ◽  
Thermal Enhancement ◽  
The Difference

Single-walled carbon nanohorns (SWNHs) have significant potential for use in photothermal therapies due to their capability to absorb near infrared light and deposit heat. Additionally, their extensive relative surface area and volume makes them ideal drug delivery vehicles. Novel multimodal treatments are envisioned in which laser excitation can be utilized in combination with chemotherapeutic-SWNH conjugates to thermally enhance the therapeutic efficacy of the transported drug. Although mild hyperthermia (41–43 °C) has been shown to increase cellular uptake of drugs such as cisplatin (CDDP) leading to thermal enhancement, studies on the effects of hyperthermia on cisplatin loaded nanoparticles are currently limited. After using a carbodiimide chemical reaction to attach CDDP to the exterior surface of SWNHs and nitric acid to incorporate CDDP in the interior volume, we determined the effects of mild hyperthermia on the efficacy of the CDDP-SWNH conjugates. Rat bladder transitional carcinoma cells were exposed to free CDDP or one of two CDDP-SWNH conjugates in vitro at 37 °C and 42 °C with the half maximal inhibitory concentration (IC50) for each treatment. The in vitro results demonstrate that unlike free CDDP, CDDP-SWNH conjugates do not exhibit thermal enhancement at 42 °C. An increase in viability of 16% and 7% was measured when cells were exposed at 42 deg compared to 37 deg for the surface attached and volume loaded CDDP-SWNH conjugates, respectively. Flow cytometry and confocal microscopy showed a decreased uptake of CDDP-SWNH conjugates at 42 °C compared to 37 °C, revealing the importance of nanoparticle uptake on the CDDP-SWNH conjugate's efficacy, particularly when hyperthermia is used as an adjuvant, and demonstrates the effect of particle size on uptake during mild hyperthermia. The uptake and drug release studies elucidated the difference in viability seen in the drug efficacy studies at different temperatures. We speculate that the disparity in thermal enhancement efficacy observed for free drug compared to the drug SWNH conjugates is due to their intrinsic size differences and, therefore, their mode of cellular uptake: diffusion or endocytosis. These experiments indicate the importance of tuning properties of nanoparticle-drug conjugates to maximize cellular uptake to ensure thermal enhancement in nanoparticle mediated photothermal-chemotherapy treatments.

scholarly journals Powering rotary molecular motors with low-intensity near-infrared light

2020 ◽  
Vol 6 (44) ◽  
pp. eabb6165
Author(s):  
Lukas Pfeifer ◽  
Nong V. Hoang ◽  
Maximilian Scherübl ◽  
Maxim S. Pshenichnikov ◽  
Ben L. Feringa
Keyword(s):  
Smart Materials ◽  
Molecular Motors ◽  
Near Infrared ◽  
In Vivo Studies ◽  
Infrared Light ◽  
Near Infrared Light ◽  
Two Photon ◽  
Low Intensity

Light-controlled artificial molecular machines hold tremendous potential to revolutionize molecular sciences as autonomous motion allows the design of smart materials and systems whose properties can respond, adapt, and be modified on command. One long-standing challenge toward future applicability has been the need to develop methods using low-energy, low-intensity, near-infrared light to power these nanomachines. Here, we describe a rotary molecular motor sensitized by a two-photon absorber, which efficiently operates under near-infrared light at intensities and wavelengths compatible with in vivo studies. Time-resolved spectroscopy was used to gain insight into the mechanism of energy transfer to the motor following initial two-photon excitation. Our results offer prospects toward in vitro and in vivo applications of artificial molecular motors.

Triggered drug release from hybrid thermoresponsive nanoparticles using near infrared light

Nanomedicine ◽  
2020 ◽  
Vol 15 (3) ◽  
pp. 219-234 ◽  
Author(s):  
Isabel Ortiz de Solorzano ◽  
Martin Prieto ◽  
Gracia Mendoza ◽  
Victor Sebastian ◽  
Manuel Arruebo
Keyword(s):  
Drug Delivery ◽  
Gold Nanoparticles ◽  
Colloidal Stability ◽  
Near Infrared ◽  
Chemical Characterization ◽  
Infrared Light ◽  
Galvanic Replacement ◽  
Heating Efficiency ◽  
Hollow Gold Nanoparticles

Aim: Developing hybrid poly(N-isopropylacrylamide)-based nanogels decorated with plasmonic hollow gold nanoparticles for on-demand drug delivery and their physico-chemical characterization, bupivacaine loading and release ability upon light irradiation, and in vitro cell viability. Materials & methods: Hollow gold nanoparticles were prepared by galvanic replacement reaction; poly(N-isopropylacrylamide)-based nanogels were synthesized via precipitation polymerization and their electrostatic coupling was accomplished using poly(allylamine hydrochloride) as cationic polyelectrolyte linker. Results & conclusion: Colloidal stability of the resulted hybrid nanovectors was demonstrated under physiological conditions together with their fast response and excellent heating efficiency after light stimulation, indicating their potential use as triggered drug-delivery vectors. Moreover, their influence on cell metabolism and cell cycle under subcytotoxic doses were studied showing excellent cytocompatibility.

scholarly journals Diagnostic Validity of Digital Imaging Fiber-Optic Transillumination (DIFOTI) and Near-Infrared Light Transillumination (NILT) for Caries in Dentine

2020 ◽  
Vol 9 (2) ◽  
pp. 420
Author(s):  
Ana Marmaneu-Menero ◽  
José Enrique Iranzo-Cortés ◽  
Teresa Almerich-Torres ◽  
José Carmelo Ortolá-Síscar ◽  
José María Montiel-Company ◽  
...  
Keyword(s):  
Confidence Interval ◽  
Qualitative Analysis ◽  
Near Infrared ◽  
Meta Analysis ◽  
Infrared Light ◽  
X Rays ◽  
Carious Lesions ◽  
Sensitivity Specificity

The objective of the study is to analyse the available evidence for the validity of the transillumination method in the diagnosis of interproximal caries. Bibliographic searches were carried out in three data bases (PubMed, Embase, Scopus) with the key words “Transillumination AND caries”. A total of 11 studies were selected for the qualitative analysis and meta-analysis. In the qualitative analysis, both in vivo and in vitro studies were included. The gold standards were tomography, digital radiography, and clinical visual diagnosis. The meta-analysis determined the sensitivity, specificity, and area below the ROC curve relative to the transillumination method in the diagnosis of caries in dentine. Meta-analysis results obtained for transillumination gave a sensitivity value of 0.69 (confidence interval: 0.54–0.81), a specificity value of 0.89 (confidence interval: 0.61–0.98), while giving an AUC value of 0.79 (confidence interval: 0.67–0.87). Transillumination is a method offering moderate validity in the diagnosis of carious lesions in dentine, there is no strong evidence that may enable us to affirm that transillumination may fully substitute X-rays in the complementary diagnosis of carious lesions

H2O2/near-infrared light-responsive nanotheronostics for MRI-guided synergistic chemo/photothermal cancer therapy

Nanomedicine ◽  
2019 ◽  
Vol 14 (16) ◽  
pp. 2189-2207
Author(s):  
Yiming Yu ◽  
Li Zhang ◽  
Miao Wang ◽  
Zhe Yang ◽  
Leping Lin ◽  
...  
Keyword(s):  
Near Infrared ◽  
Tumor Model ◽  
Mri Contrast Agent ◽  
Infrared Light ◽  
Antitumor Effects ◽  
Mri Contrast ◽  
Nir Light ◽  
Nir Laser

Aim: To develop a H2O2/near-infrared (NIR) laser light-responsive nanoplatform (manganese-doped Prussian blue@polypyrrole [MnPB@PPy]) for synergistic chemo/photothermal cancer theranostics. Materials & methods: Doxorubicin (DOX) was loaded onto the surface of polypyrrole shells. The in vitro and in vivo MRI performance and anticancer effects of these nanoparticles (NPs) were evaluated. Results: The MnPB@PPy NPs could not only generate heat under NIR laser irradiation for cancer photothermal therapy but also act as an excellent MRI contrast agent. The loaded DOX could be triggered to release by both NIR light and H2O2 to enhance synergistic therapeutic efficacy. The antitumor effects were confirmed by in vitro cellular cytotoxicity assays and in vivo treatment in a xenograft tumor model. Conclusion: The designed H2O2/NIR light-responsive MnPB@PPy-DOX NPs hold great potential for future biomedical applications.

Targeted gold nanoshelled hybrid nanocapsules encapsulating doxorubicin for bimodal imaging and near-infrared triggered synergistic therapy of Her2-positve breast cancer

2020 ◽  
Vol 35 (3) ◽  
pp. 430-445
Author(s):  
Qi Dong ◽  
Caifeng Wan ◽  
Hong Yang ◽  
Dongdong Zheng ◽  
Li Xu ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Magnetic Resonance Imaging ◽  
Magnetic Resonance ◽  
Near Infrared ◽  
Average Diameter ◽  
Infrared Light ◽  
Resonance Imaging ◽  
Her2 Positive ◽  
Bimodal Imaging

A multifunctional targeted nanoplatform combining photothermal therapy and chemotherapy has emerged as a promising strategy for comprehensive therapies of breast cancer. In this study, we constructed human epidermal growth factor receptor 2 (Her2)-targeted gold nanoshelled poly(lactic- co-glycolic acid) hybrid nanocapsules encapsulating perfluorooctyl bromide, superparamagnetic iron oxide nanoparticles, and doxorubicin (Her2-GPDH nanocapsules) as theranostic agent for bimodal ultrasound/magnetic resonance imaging and synergistic photothermal-chemotherapy of Her2-postive breast cancer cells. Her2–GPDH nanocomposites possessed well-defined spherical morphology, and the average diameter was about 296 nm with good dispersion. Targeting assays demonstrated that Her2–GPDH nanocapsules exhibited higher targeting binding to Her2-positive SKBR3 cells than Her2-negative MDA-MB-231cells. The encapsulation efficiency and the loading content of doxorubicin in Her2–GPDH nanocapsules were 39 ± 1.45% and 3.8 ± 0.52%, respectively, and the agent exhibited pH-responsive and near-infrared light-triggered stepwise release behavior of doxorubicin. In vitro, the agent had potential to serve as feasible candidate for ultrasound imaging and T2-weighted magnetic resonance imaging with a relatively high relaxivity. Cell experiments confirmed that the agent had significant photothermal cytotoxicity on SKBR3 cells, and the combined photothermal–chemotherapy could significantly enhance the anti-tumor effect. In summary, the present Her2–GPDH nanocapsules, a novel multifunctional nanoplatform, will offer a new way for early bimodal molecular-level diagnosis and synergistic treatment of Her2-positve breast cancer.

scholarly journals Near infrared light exposure is associated with increased mitochondrial membrane potential in retinal pigmented epithelial cells

2020 ◽  
Vol 19 (10) ◽  
pp. 1455-1459
Author(s):  
Catherine Rono ◽  
Tiffany R Oliver
Keyword(s):  
Membrane Potential ◽  
Epithelial Cells ◽  
Mitochondrial Membrane Potential ◽  
Mitochondrial Membrane ◽  
Near Infrared ◽  
Light Exposure ◽  
Infrared Light ◽  
Near Infrared Light ◽  
Retinal Pigmented Epithelial Cells

The goal of this study was to characterize the effect of near-infrared light exposure on mitochondrial membrane potential, in vitro.

Potential of solubility, enzymatic methods and NIRS to predict in situ rumen escape protein

1997 ◽  
Vol 45 (2) ◽  
pp. 291-306 ◽  
Author(s):  
J.L. De Boever ◽  
B.G. Cottyn ◽  
J.M. Vanacker ◽  
C.V. Boucque
Keyword(s):  
Phosphate Buffer ◽  
Near Infrared ◽  
Streptomyces Griseus ◽  
Maize Silage ◽  
Near Infrared Reflectance ◽  
In Vitro Method ◽  
Rumen Degradation ◽  
The Difference

The percentage of feed protein escaping rumen degradation was measured by the in situ method (%EPsitu) for 29 compound feeds, untreated and formaldehyde-treated soyabean meal and 12 forages: 3 grass silages, 2 maize silages, fresh grass, grass hay, fodder beets, fresh potatoes, ensiled beet pulp, chopped ear-maize silage and brewers' grains. Loss of particles through bag pores was determined by the difference between the washable fraction (W) and the fraction soluble in borate-phosphate buffer at pH 6.7 (S). W - S was most pronounced for compound feeds (on average 14.4 percentage units), for brewers' grains and maize silages. A correction of %EPsitu, assuming that W - S degrades like the potentially degradable fraction, was not appropriate. Solubility in borate-phosphate buffer after 1 h, enzymic degradability by protease from Streptomyces griseus or ficin after 1, 6 and 24 h and near infrared reflectance spectroscopy (NIRS) (for compound feeds alone) were examined as a routine method to predict %EPsitu. With the buffer and S. griseus the effect of pH (6.7 vs. 8.0) and at pH 8.0 the effect of amount of substrate (500-mg sample vs. 20 mg N) were tested. With ficin, 500-mg samples were incubated at pH 6.7. Predictions were better when compound feeds and forages were considered separately. However, the best in vitro method was different for the 2 feed categories, being solubility in buffer for the compound feeds and enzymic degradation of a constant amount of protein with S. griseus at pH 8.0 for forages. NIRS showed potential to predict %EPsitu of compound feeds, but needs more reference samples. The Dutch feed tables appeared more accurate than the best in vitro method for compound feeds, but was too inaccurate for some forages like fodder beets, maize silage and ear-maize silage.

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