Near-infrared light-triggered thermochemotherapy of cancer using a polymer-gold nanorod conjugate

Laser Responsive Cisplatin-Gold Nano-Assembly Synergizes the Effect of Cisplatin With Compliance

Cisplatin therapy faces low bioavailability and clastogenic potential limitations. Early payload leakage of nanocarriers may impair adequate therapeutic efficacy. We propose encapsulation of cisplatin in such nanocarrier that can be externally stimulated for high payload release and enhanced toxicity at site of action. Cisplatin conjugated gold nanorods (Pt-AuNRs) have been synthesized and characterized through UV visible spectroscopy, dynamic light scattering and transmission electron microscopy. Physico-chemical characterization through X-ray photon spectrometry confirms the covalent linkage between linker and aquated cisplatin with AuNRs. Laser exposure (850 nm, CW) enabled ~15-fold payload release from Pt-AuNRs nano-assembly, which is quite high (P < 0.0001) compared to non-stimulated conditions. The median growth inhibitory concentration (GI₅₀) after laser exposure of Pt-AuNRs was ~11- and 13-fold low compared to corresponding Pt-AuNRs without laser exposure and cisplatin respectively, in sarcoma cells. Synergistic therapeutic difference is more significant (P < 0.01), at lower concentrations of Pt-AuNRs (0.5-10 μg/mL). Pt-AuNRs photothermal therapy indicates a convincible association of over-production of reactive oxygen species (P < 0.0001) and synergistic therapeutic efficacy. Clastogenic potential is found non-significant for Pt-AuNRs (10 μg/mL). Cisplatin nanoconjugate shows biocompatibility against blood cells. In conclusion, laser-stimulated Pt-AuNRs appear a promising drug delivery with synergistic toxic potential against cancer while attenuating cisplatin toxicity.

NIR responsive AuNR/pNIPAM/PEGDA inverse opal hydrogel microcarriers for controllable drug delivery

A novel inverse opal microcarrier with both NIR-controlled release and visual color changes for drug delivery.

A Review on Cancer Therapy Based on the Photothermal Effect of Gold Nanorod

Background:

Cancer causes millions of deaths and huge economic losses every year. The currently practiced methods for cancer therapy have many defects, such as side effects, low curate rate, and discomfort for patients.

Objective:

Herein, we summarize the applications of gold nanorods (AuNRs) in cancer therapy based on their photothermal effect-the conversion of light into local heat under irradiation.

Methods:

The recent advances in the synthesis and regulation of AuNRs, and facile surface functionalization further facilitate their use in cancer treatment. For cancer therapy, AuNRs need to be modified or coated with biocompatible molecules (e.g. polyethylene glycol) and materials (e.g. silicon) to reduce the cytotoxicity and increase their biocompatibility, stability, and retention time in the bloodstream. The accumulation of AuNRs in cancerous cells and tissues is due to the high leakage in tumors or the specific interaction between the cell surface and functional molecules on AuNRs such as antibodies, aptamers, and receptors.

Results:

AuNRs are employed not only as therapeutics to ablate tumors solely based on the heat produced under laser that could denature protein and activate the apoptotic pathway, but also as synergistic therapies combined with photodynamic therapy, chemotherapy, and gene therapy to kill cancer more efficiently. More importantly, other materials like TiO2, graphene oxide, and silicon, etc. are incorporated on the AuNR surface for multimodal cancer treatment with high drug loadings and improved cancer-killing efficiency. To highlight their applications in cancer treatment, examples of therapeutic effects both in vitro and in vivo are presented.

Conclusion:

AuNRs have potential applications for clinical cancer therapy.

Near-infrared light-responsive UCST-nanogels using an efficient nickel-bis(dithiolene) photothermal crosslinker

A new kind of near-infrared (NIR) light-responsive polymer nanogel is demonstrated.

Tumor vasodilation by N-Heterocyclic carbene-based nitric oxide delivery triggered by high-intensity focused ultrasound and enhanced drug homing to tumor sites for anti-cancer therapy

Nitric oxide (NO) is widely known as an effective vasodilator at low concentrations. Drug delivery systems combined with NO can dilate blood vessels surrounding tumor tissues, and the drug accumulation in tumors is accelerated by the enhanced permeability and retention effect, leading to an improvement in the anti-tumor effect. N-heterocyclic carbene-based NO donors (e.g., 1,3-bis-(2,4,6-trimethylphenyl)imidazolylidene nitric oxide (IMesNO) have been developed for stable NO storing in air and water, and NO release by thermolysis. Herein, we demonstrated on-demand NO release by high-intensity focused ultrasound (HIFU) as a stimulus, which generated high heat and exerted an ablation effect when treated in vivo. We demonstrated IMesNO to be a HIFU-responsive NO donor and its potential application in vivo using IMesNO-loaded micelles. Moreover, IMesNO-loaded micelles mixed with drug-loaded micelles (IMesNO/DOX@MCs) showed acceleration of drug accumulation in tumor sites and enhanced tumor growth inhibition. Thus, our findings suggest a potential clinical bioapplication of NO-releasing drug-loaded micelles owing to the therapeutic function of NO and HIFU treatment for anti-cancer therapy.

Near-infrared biophotonics-based nanodrug release systems and their potential application for neuro-disorders

INTRODUCTION

Near-infrared ray (NIR)-responsive 'smart' nanoagents allow spatial and temporal control over the drug delivery process, noninvasively, without affecting healthy tissues and therefore they possess high potential for on-demand, targeted drug/gene delivery. Various NIR-responsive drug/gene delivery techniques are under investigation for peripheral disorders (especially for cancer). Nonetheless, their potential not been extensively examined for brain biomedical application.

AREAS COVERED

This review focuses on NIR-responsive characteristics of different NIR-nanobiophotonics-based nanoagents and associated drug delivery strategies. Together with their ongoing applications for peripheral drug delivery, we have highlighted the opportunities, challenges and possible solutions of NIR-nanobiophotonics for potential brain drug delivery.

EXPERT OPINION

NIR-nanobiophotonics can be considered superior among all photo-controlled drug/gene delivery approaches. Future work should focus on coupling NIR with biocompatible nanocarriers to determine the physiological compatibility of this approach. Their applications should be extended beyond the peripheral body region to brain region. Transient or intermittent NIR exposure strategies may be more accommodating for brain physiological ambience in order to minimize or avoid the possible deleterious thermal effect. In addition, while most studies are centered around the first NIR spectral window (700-1000 nm), the potential of second (1100-1350 nm) and third (1600-1870 nm) windows must be explored.

PEG-PCL-based nanomedicines: A biodegradable drug delivery system and its application

The lack of efficient therapeutic options for many severe disorders including cancer spurs demand for improved drug delivery technologies. Nanoscale drug delivery systems based on poly(ethylene glycol)-poly(ε-caprolactone) copolymers (PEG-PCL) represent a strategy to implement therapies with enhanced drug accumulation at the site of action and decreased off-target effects. In this review, we discuss state-of-the-art nanomedicines based on PEG-PCL that have been investigated in a preclinical setting. We summarize the various synthesis routes and different preparation methods used for the production of PEG-PCL nanoparticles. Additionally, we review physico-chemical properties including biodegradability, biocompatibility, and drug loading. Finally, we highlight recent therapeutic applications investigated in vitro and in vivo using advanced systems such as triggered release, multi-component therapies, theranostics, or gene delivery systems.

Anti-EGFR Antibody Conjugation of Fucoidan-Coated Gold Nanorods as Novel Photothermal Ablation Agents for Cancer Therapy

The development of novel photothermal ablation agents as cancer nanotheranostics has received a great deal of attention in recent decades. Biocompatible fucoidan (Fu) is used as the coating material for gold nanorods (AuNRs) and subsequently conjugated with monoclonal antibodies against epidermal growth factor receptor (anti-EGFR) as novel photothermal ablation agents for cancer nanotheranostics because of their excellent biocompatibility, biodegradability, nontoxicity, water solubility, photostability, ease of surface modification, strongly enhanced absorption in near-infrared (NIR) regions, target specificity, minimal invasiveness, fast recovery, and prevention of damage to normal tissues. Anti-EGFR Fu-AuNRs have an average particle size of 96.37 ± 3.73 nm. Under 808 nm NIR laser at 2 W/cm² for 5 min, the temperature of the solution containing anti-EGFR Fu-AuNRs (30 μg/mL) increased by 52.1 °C. The anti-EGFR Fu-AuNRs exhibited high efficiency for the ablation of MDA-MB-231 cells in vitro. In vivo photothermal ablation exhibited that tumor tissues fully recovered without recurrence and finally were reconstructed with normal tissues by the 808 nm NIR laser irradiation after injection of anti-EGFR Fu-AuNRs. These results suggest that the anti-EGFR Fu-AuNRs would be novel photoablation agents for future cancer nanotheranostics.

Chemo-photothermal therapy of cancer cells using gold nanorod-cored stimuli-responsive triblock copolymer

The combination of photothermal therapy and chemotherapy, when carefully planned, has been shown to be an effective cancer treatment option clinically and preclinically.

A Fibrous Localized Drug Delivery Platform with NIR-Triggered and Optically Monitored Drug Release

Implantable localized drug delivery systems (LDDSs) with intelligent functionalities have emerged as a powerful chemotherapeutic platform in curing cancer. Developing LDDSs with rationally controlled drug release and real-time monitoring functionalities holds promise for personalized therapeutic protocols but suffers daunting challenges. To overcome such challenges, a series of porous Yb(3+)/Er(3+) codoped CaTiO3 (CTO:Yb,Er) nanofibers, with specifically designed surface functionalization, were synthesized for doxorubicin (DOX) delivery. The content of DOX released could be optically monitored by increase in the intensity ratio of green to red emission (I550/I660) of upconversion photoluminescent nanofibers under 980 nm near-infrared (NIR) excitation owing to the fluorescence resonance energy transfer (FRET) effect between DOX molecules and the nanofibers. More importantly, the 808 nm NIR irradiation enabled markedly accelerated DOX release, confirming representative NIR-triggered drug release properties. In consequence, such CTO:Yb,Er nanofibers presented significantly enhanced in vitro anticancer efficacy under NIR irradiation. This study has thus inspired another promising fibrous LDDS platform with NIR-triggered and optics-monitored DOX releasing for personalized tumor chemotherapy.

Temperature-Responsive Smart Nanocarriers for Delivery Of Therapeutic Agents: Applications and Recent Advances

Smart drug delivery systems (DDSs) have attracted the attention of many scientists, as carriers that can be stimulated by changes in environmental parameters such as temperature, pH, light, electromagnetic fields, mechanical forces, etc. These smart nanocarriers can release their cargo on demand when their target is reached and the stimulus is applied. Using the techniques of nanotechnology, these nanocarriers can be tailored to be target-specific, and exhibit delayed or controlled release of drugs. Temperature-responsive nanocarriers are one of most important groups of smart nanoparticles (NPs) that have been investigated during the past decades. Temperature can either act as an external stimulus when heat is applied from the outside, or can be internal when pathological lesions have a naturally elevated termperature. A low critical solution temperature (LCST) is a special feature of some polymeric materials, and most of the temperature-responsive nanocarriers have been designed based on this feature. In this review, we attempt to summarize recent efforts to prepare innovative temperature-responsive nanocarriers and discuss their novel applications.