Chitosan/fucoidan multilayer coating of gold nanorods as highly efficient near-infrared photothermal agents for cancer therapy.

Photothermal therapy (PTT) using chitosan/fucoidan multilayer coating of gold nanorods (CS/F-GNRs) has emerged as an alternative strategy for cancer therapy. In this study, biocompatible CS/F-GNRs were synthesized as a new generation of photothermal therapeutic agents for in vivo cancer treatments owing to their good biocompatibility, photostability, and strong absorption in the near-infrared (NIR) region. The CS/F-GNRs showed a good size distribution (51.87 ± 3.03 nm), and the temperature variation of the CS/F-GNRs increased by 54.4 °C after laser irradiation (1.0 W/cm2) for 5 min. The in vitro photothermal efficiency of CS/F-GNRs indicated that significantly more cancer cells were killed under laser irradiation at 1.0 W/cm2 for 5 min. On the 20th day of treatment, the MDA-MB-231 tumor cells in mice treated with CS/F-GNRs under laser irradiation had almost completely disappeared. Therefore, the biocompatible CS/F-GNRs have shown great promise as safe and highly efficient near-infrared photothermal agents for future cancer therapy.

Photo-based PDT/PTT dual model killing and imaging of cancer cells using phycocyanin-polypyrrole nanoparticles.

Photodynamic therapy (PDT) and photothermal therapy (PTT) using nanoparticles have gained significant attention for its therapeutic effect for cancer treatment. In the present study, we fabricated polypyrrole nanoparticles by employing bovine serum albumin-phycocyanin complex and the formulated particles were stable in various physiological solutions like water, phosphate buffered saline and culture media. The formulated nanoparticles did not cause any noticeable toxicity to MDA-MB-231 and HEK-293 cells. The obtained nanoparticles effectively killed MDA-MB-231 cells in a dual way upon laser illumination, one is through phycocyanin propagated reactive oxygen species (PDT) upon laser illumination and in another way it eradicated the treated cells by converting optical energy into heat energy (PTT). Additionally, the nanoparticles generated good amplitude of ultrasound signals under photoacoustic imaging (PAT) system that facilitates imaging of treated cells. In conclusion, the fabricated particles could be used as a multimodal therapeutic agent for treatment of cancer in the biomedical field.

Prussian blue decorated mesoporous silica hybrid nanocarriers for photoacoustic imaging-guided synergistic chemo-photothermal combination therapy.

The fabrication of nanotherapeutic systems capable of stimuli-responsive drug delivery and photoacoustic imaging (PAI)-guided photothermal therapy (PTT) is considered significant for chemo-photothermal therapy applications in cancer therapy. In the present study, the Prussian blue nanoflake (PBNF) decorated mesoporous silica hybrid nanoparticle (PB@MSH-EDA NPs) is reported for PAI-guided chemo-photothermal therapy applications. The amine group enriched mesoporous silica channels can be used to encapsulate an anticancer drug for chemotherapy, and the surface decorated PBNFs can convert a near-infrared (NIR) laser (808 nm) into heat for photothermal therapy and can also be used for PAI applications. The PB@MSH-EDA NPs show pH-responsive drug release efficiency under acidic pH (pH 5.0 and 4.0) conditions. Furthermore, the PB@MSH-EDA NPs system shows strong NIR laser absorption and photothermal conversion efficiency under 808 nm laser irradiation. The in vitro experimental result shows that the PB@MSH-EDA NPs are biocompatible and could be efficiently taken up by MDA-MB-231 cells. In addition, the in vivo results demonstrate that the tumor-bearing mice fully recovered after injecting the drug (Dox)-loaded PB@MSH-EDA/Dox NPs and being further irradiated with the 808 nm laser. We believe that the PB@MSH-EDA NPs system could be utilized as an efficient PAI-guided chemo-photothermal therapy agent for the detection and treatment of tumors in an emerging cancer therapy application.

Biocompatible Chitosan Oligosaccharide Modified Gold Nanorods as Highly Effective Photothermal Agents for Ablation of Breast Cancer Cells.

Photothermal therapy (PTT) using biocompatible nanomaterials have recently attracted much attention as a novel candidate technique for cancer therapy. In this work we report the performance of newly synthesized multidentate chitosan oligosaccharide modified gold nanorods (AuNRs-LA-COS) as novel agents for PTT of cancer cells due to their excellent biocompatibility, photothermal stability, and high absorption in the near-infrared (NIR) region. The AuNRs-LA-COS exhibit a strong NIR absorption peak at 838 nm with a mean length of 26 ± 3.1 nm and diameter of 6.8 ± 1.7 nm, respectively. The temperature of AuNRs-LA-COS rapidly reached 52.6 °C for 5 min of NIR laser irradiation at 2 W/cm². The AuNRs-LA-COS had very low cytotoxicity and exhibited high efficiency for the ablation of breast cancer cells in vitro. The tumor-bearing mice were completely ablated without tumor recurrence after photothermal treatment with AuNRs-LA-COS (25 µg/mL) under laser irradiation. In summary, this study demonstrated that AuNRs-LA-COS with laser irradiation as novel agents pave an alternative way for breast cancer therapy and hold great promise for clinical trials in the near future.

Marine natural pigments as potential sources for therapeutic applications.

In recent years, marine natural pigments have emerged as a powerful alternative in the various fields of food, cosmetic, and pharmaceutical industries because of their excellent biocompatibility, bioavailability, safety, and stability. Marine organisms are recognized as a rich source of natural pigments such as chlorophylls, carotenoids, and phycobiliproteins. Numerous studies have shown that marine natural pigments have considerable medicinal potential and promising applications in human health. In this review, we summarize the marine natural pigments as potential sources for therapeutic applications, including: antioxidant, anticancer, antiangiogenic, anti-obesity, anti-inflammatory activities, drug delivery, photothermal therapy (PTT), photodynamic therapy (PDT), photoacoustic imaging (PAI), and wound healing. Marine natural pigments will offer a better platform for future theranostic applications.

Magnetic hydroxyapatite: a promising multifunctional platform for nanomedicine application.

In this review, specific attention is paid to the development of nanostructured magnetic hydroxyapatite (MHAp) and its potential application in controlled drug/gene delivery, tissue engineering, magnetic hyperthermia treatment, and the development of contrast agents for magnetic resonance imaging. Both magnetite and hydroxyapatite materials have excellent prospects in nanomedicine with multifunctional therapeutic approaches. To date, many research articles have focused on biomedical applications of nanomaterials because of which it is very difficult to focus on any particular type of nanomaterial. This study is possibly the first effort to emphasize on the comprehensive assessment of MHAp nanostructures for biomedical applications supported with very recent experimental studies. From basic concepts to the real-life applications, the relevant characteristics of magnetic biomaterials are patented which are briefly discussed. The potential therapeutic and diagnostic ability of MHAp-nanostructured materials make them an ideal platform for future nanomedicine. We hope that this advanced review will provide a better understanding of MHAp and its important features to utilize it as a promising material for multifunctional biomedical applications.

Hydroxyapatite Coated Iron Oxide Nanoparticles: A Promising Nanomaterial for Magnetic Hyperthermia Cancer Treatment.

Targeting cancer cells without injuring normal cells is the prime objective in treatment of cancer. In this present study, solvothermal and wet chemical precipitation techniques were employed to synthesize iron oxide (IO), hydroxyapatite (HAp), and hydroxyapatite coated iron oxide (IO-HAp) nanoparticles for magnetic hyperthermia mediated cancer therapy. The synthesized well dispersed spherical IO-HAp nanoparticles, magnetite, and apatite phases were confirmed by X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR) and Field emission transmission electron microscopy (FETEM) with Energy Dispersive X-ray spectroscopy (EDS). The non-toxic behavior of synthesized IO-HAp nanoparticles was confirmed by cytotoxicity assay (Trypan blue and MTT assay). The synthesized nanoparticles revealed a remarkable magnetic saturation of 83.2 emu/g for IO and 40.6 emu/g for IO-HAp nanoparticles in presence of 15,000 Oe (1.5 T) magnetic field at room temperature (300 K). The magnetic hyperthermia study that was performed with IO-HAp nanoparticles showed an excellent hyperthermia effect (SAR value 85 W/g) over MG-63 osteosarcoma cells. The in vitro hyperthermia temperature (~45 °C) was reached within 3 min, which shows a very high efficiency and kills nearly all of the experimental MG-63 osteosarcoma cells within 30 min exposure. These results could potentially open new perceptions for biomaterials that are aimed for anti-cancer therapies based on magnetic hyperthermia.

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.

Multifunctional biocompatible chitosan-polypyrrole nanocomposites as novel agents for photoacoustic imaging-guided photothermal ablation of cancer.

Cancer nanotechnology is emerging as one of the promising strategies combining photothermal therapy (PTT) and photoacoustic imaging (PAI) for the treatment of breast cancer and it has received considerable attention in the recent years because it is minimally invasive, prevents damage to non-targeted regions, permits fast recovery, and involves breast cancer imaging. The present study demonstrates multifunctional biocompatible chitosan-polypyrrole nanocomposites (CS-PPy NCs) as novel agents for photoacoustic imaging-guided photothermal ablation of cancer because of their biocompatibility, conductivity, stability, and strong near-infrared (NIR) absorbance. The CS-PPy NCs are spherical in shape and range 26-94 nm in size with a mean value of 50.54 ± 2.56 nm. The in vitro results demonstrated good biocompatibility of CS-PPy NCs, which can be used in PTT for cancer cells under 808-nm NIR laser irradiation. Tumor-bearing mice fully recovered after treatment with CS-PPy NCs and NIR 808-nm laser irradiation compared to the corresponding control groups. Our research highlights the promising potential of using CS-PPy NCs for photoacoustic imaging-guided photothermal ablation of cancer in preclinical animals, which should be verified in future clinical trials.

Synthesis of surface capped mesoporous silica nanoparticles for pH-stimuli responsive drug delivery applications.

Mesoporous silica-based drug delivery carriers mostly require appropriate surface modifications to improve their drug delivery efficiency and to reduce their adverse side effects. In the present work, we have synthesised mesoporous silica nanoparticles and their surface was covered by using capping units such as tetrathio-maleimide (TTM) via a "host-guest" complexation mechanism for pH-responsive drug delivery applications. The surface-functionalised melamine (Mela) groups on the outer surface of the mesoporous silica nanoparticles act as "hosts" and the surface capped TTM units act as "guests" during the surface capping of the mesoporous silica nanoparticles via the "host-guest" complexation approach. After the encapsulation of cargoes into the mesopore channels, the melamine functional groups were covalently immobilised onto the outer surface of the cargo loaded MSNs and then the TTM units were introduced onto the outer surface of the silica nanoparticles as "gatekeepers" to obtain surface capped mesoporous silica (MSN@Mela@TTM/RhB) NPs to protect the loaded cargo molecules inside the mesopore channels and to prevent their premature leakage. The surface-capped TTM units controlled the drug release behavior with respect to the pH of the release medium. In this study, we used rhodamine B (RhB) as a model cargo to study the loading and pH-responsive release behavior of the MSN@Mela@TTM NPs. The encapsulated RhB molecules were retained inside the mesopore channels at physiological pH (pH 7.4) conditions while an enhanced release occurred at acidic pH (pH 5.0 and 4.0) conditions, respectively. Furthermore, the in vitro biocompatibility and the intracellular uptake efficiency of the synthesised MSNs@Mela@TTM NPs were examined by using the MDA-MB-231 cell line. The experimental results suggest that the MSNs@Mela@TTM nanoparticles are biocompatible and could be utilised for pH-stimuli responsive drug delivery applications.

In Vitro Photodynamic Effect of Phycocyanin against Breast Cancer Cells.

C-phycocyanin, a natural blue-colored pigment-protein complex was explored as a novel photosensitizer for use in low-level laser therapy under 625-nm laser illumination. C-phycocyanin produced singlet oxygen radicals and the level of reactive oxygen species (ROS) were raised in extended time of treatment. It did not exhibit any visible toxic effect in the absence of light. Under 625-nm laser irradiation, c-phycocyanin generated cytotoxic stress through ROS induction, which killed MDA-MB-231 breast cancer cells depending on concentrations. Different fluorescent staining of laser-treated cells explored apoptotic cell death characteristics like the shrinking of cells, cytoplasmic condensation, nuclei cleavage, and the formation of apoptotic bodies. In conclusion, phycocyanin is a non-toxic fluorescent pigment that can be used in low-level light therapy.