Protein-Poly(amino acid) Nanocore-Shell Mediated Synthesis of Branched Gold Nanostructures for Computed Tomographic Imaging and Photothermal Therapy of Cancer

Protein nanoparticles as drug delivery systems for cancer theranostics

Protein-based nanoparticles have garnered significant attention in theranostic applications due to their superior biocompatibility, exceptional biodegradability and ease of functionality. Compared to other nanocarriers, protein-based nanoparticles offer additional advantages, including biofunctionality and precise molecular recognition abilities, which make them highly effective in navigating complex biological environments. Moreover, proteins can serve as powerful tools with self-assembling structures and reagents that enhance cell penetration. And their derivation from abundant renewable sources and ability to degrade into harmless amino acids further enhance their suitability for biomedical applications. However, protein-based nanoparticles have so far not realized their full potential. In this review, we summarize recent advances in the use of protein nanoparticles in tumor diagnosis and treatment and outline typical methods for preparing protein nanoparticles. The review of protein nanoparticles may provide useful new insights into the development of biomaterial fabrication.

Magnetically navigated microbubbles coated with albumin/polyarginine and superparamagnetic iron oxide nanoparticles

While microbubbles (MB) are routinely used for ultrasound (US) imaging, magnetic MB are increasingly explored as they can be guided to specific sites of interest by applied magnetic field gradient. This requires the MB shell composition tuning to prolong MB stability and provide functionalization capabilities with magnetic nanoparticles. Hence, we developed air-filled MB stabilized by a protein-polymer complex of bovine serum albumin (BSA) and poly-L-arginine (pArg) of different molecular weights, showing that pArg of moderate molecular weight distribution (15-70 kDa) enabled MB with greater stability and acoustic response while preserving MB narrow diameters and the relative viability of THP-1 cells after 48 h of incubation. After MB functionalization with superparamagnetic iron oxide nanoparticles (SPION), magnetic moment values provided by single MB confirmed the sufficient SPION deposition onto BSA + pArg MB shells. During MB magnetic navigation in a blood vessel mimicking phantom with magnetic tweezers and in a Petri dish with adherent mouse renal carcinoma cell line, we demonstrated the effectiveness of magnetic MB localization in the desired area by magnetic field gradient. Magnetic MB co-localization with cells was further exploited for effective doxorubicin delivery with drug-loaded MB. Taken together, these findings open new avenues in control over albumin MB properties and magnetic navigation of SPION-loaded MB, which can envisage their applications in diagnostic and therapeutic needs.

Reproducible Synthesis of Biocompatible Albumin Nanoparticles Designed for Intra-articular Administration of Celecoxib to Treat Osteoarthritis

Osteoarthritis (OA) is the most common form of arthritis, with intra-articular (IA) delivery of therapeutics being the current best option to treat pain and inflammation. However, IA delivery is challenging due to the rapid clearance of therapeutics from the joint and the need for repeated injections. Thus, there is a need for long-acting delivery systems that increase the drug retention time in joints with the capacity to penetrate OA cartilage. As pharmaceutical utility also demands that this is achieved using biocompatible materials that provide colloidal stability, our aim was to develop a nanoparticle (NP) delivery system loaded with the COX-2 inhibitor celecoxib that can meet these criteria. We devised a reproducible and economical method to synthesize the colloidally stable albumin NPs loaded with celecoxib without the use of any of the following conditions: high temperatures at which albumin denaturation occurs, polymer coatings, oils, Class 1/2 solvents, and chemical protein cross-linkers. The spherical NP suspensions were biocompatible, monodisperse with average diameters of 72 nm (ideal for OA cartilage penetration), and they were stable over 6 months at 4 °C. Moreover, the NPs loaded celecoxib at higher levels than those required for the therapeutic response in arthritic joints. For these reasons, they are the first of their kind. Labeled NPs were internalized by primary human articular chondrocytes cultured from the knee joints of OA patients. The NPs reduced the concentration of inflammatory mediator prostaglandin E2 released by the primaries, an indication of retained bioactivity following NP synthesis. Similar results were observed in lipopolysaccharide-stimulated human THP-1 monocytes. The IA administration of these NPs is expected to avoid side-effects associated with oral administration of celecoxib and to maintain a high local concentration in the knee joint over a sustained period. They are now ready for evaluation by IA administration in animal models of OA.

Progress of Nanomaterials-Based Photothermal Therapy for Oral Squamous Cell Carcinoma

Oral squamous cell carcinoma (OSCC) is one of the top 15 most prevalent cancers worldwide. However, the current treatment models for OSCC (e.g., surgery, chemotherapy, radiotherapy, and combination therapy) present several limitations: damage to adjacent healthy tissue, possible recurrence, low efficiency, and severe side effects. In this context, nanomaterial-based photothermal therapy (PTT) has attracted extensive research attention. This paper reviews the latest progress in the application of biological nanomaterials for PTT in OSCC. We divide photothermal nanomaterials into four categories (noble metal nanomaterials, carbon-based nanomaterials, metal compounds, and organic nanomaterials) and introduce each category in detail. We also mention in detail the drug delivery systems for PTT of OSCC and briefly summarize the applications of hydrogels, liposomes, and micelles. Finally, we note the challenges faced by the clinical application of PTT nanomaterials and the possibility of further improvement, providing direction for the future research of PTT in OSCC treatment.

Biodegradable Protein-Stabilized Inorganic Nanoassemblies for Photothermal Radiotherapy of Hepatoma Cells

Inorganic nanomaterials require optimal engineering to retain their functionality yet can also biodegrade within physiological conditions to avoid chronic accumulation in their native form. In this work, we have developed gelatin-stabilized iron oxide nanoclusters having a primary crystallite size of ∼10 nm and surface-functionalized with indocyanine green (ICG)-bound albumin-stabilized gold nanoclusters (Prot-IONs). The Prot-IONs are designed to undergo disintegration in an acidic microenvironment of tumor in the presence of proteolytic enzymes within 72 h. These nanoassemblies demonstrate bio- and hemocompatibility and show significant photothermal efficiency due to strong near infrared absorption contributed by ICG. The surface gold nanoclusters could efficiently sensitize hepatoma cells to γ-irradiation with substantial cytoskeletal and nuclear damage. Sequential irradiation of Prot-ION-treated cancer cells with near infrared (NIR) laser (λ = 750 nm) and γ-irradiation could cause ∼90% cell death compared to single treatment groups at a lower dose of nanoparticles. The superparamagnetic nature of Prot-IONs imparted significant relaxivity (∼225 mM^-1 s^-1) for T₂-weighted magnetic resonance imaging. Additionally, they could also be engaged as photoacoustic and NIR imaging contrast agents. This work demonstrates bioeliminable inorganic nanoassemblies with significant theranostic potential.

A Review: Potential Application and Outlook of Photothermal Therapy in Oral Cancer Treatment

As one of the most common malignant tumors, oral cancer threatens people's health worldwide. However, traditional therapies, including surgery, radiotherapy, and chemotherapy can't meet the requirement of cancer cure. Photothermal therapy (PTT) has attracted widespread attentions for its advantages of the noninvasive process, few side effects, and promising tumor ablation. Up to now, three types of photothermal agents (PTAs) have been widely employed in oral cancer therapies, which involve metallic materials, carbon-based materials, and organic materials. Previous research mainly introduced hybrid materials due to benefits from the synergistic effect of multiple functions. In this review, we present the advancement of each type PTAs for oral cancer treatment in recent years. In each part, we introduce the properties and synthesis of each PTA, summarize the current studies, and analyze their potential applications. Furthermore, we discuss the status quo and the deficiencies hindering the clinical application of PTT, based on which gives the perspective of its future developing directions.

Delineating the Role of Tailored Gold Nanostructures at the Biointerface

Gold (Au) has emerged as a superior element, because of its widespread applications in electronic and medical fields. The desirable physical, chemical, optical, and inherent enzyme-like properties of Au are efficiently exploited for detection, diagnostic, and therapeutic purposes. Au offers a unique advantage of fabricating gold nanostructures (GNS) having exact physical, chemical, optical, and enzyme-like properties required for the specific biomedical application. In this Review, the emerging trend of GNS for various biomedical applications is highlighted. Some notable structural and chemical modifications achieved for the detection of biomolecules, pathogens, diagnosis of diseases, and therapeutic applications are discussed in brief. The limitations of GNS during biomedical usage are highlighted and the way forward to overcome these limitations are discussed.

Design and Application of Near-Infrared Nanomaterial-Liposome Hybrid Nanocarriers for Cancer Photothermal Therapy

Liposomes are attractive carriers for targeted and controlled drug delivery receiving increasing attention in cancer photothermal therapy. However, the field of creating near-infrared nanomaterial-liposome hybrid nanocarriers (NIRN-Lips) is relatively little understood. The hybrid nanocarriers combine the dual superiority of nanomaterials and liposomes, with more stable particles, enhanced photoluminescence, higher tumor permeability, better tumor-targeted drug delivery, stimulus-responsive drug release, and thus exhibiting better anti-tumor efficacy. Herein, this review covers the liposomes supported various types of near-infrared nanomaterials, including gold-based nanomaterials, carbon-based nanomaterials, and semiconductor quantum dots. Specifically, the NIRN-Lips are described in terms of their feature, synthesis, and drug-release mechanism. The design considerations of NIRN-Lips are highlighted. Further, we briefly introduced the photothermal conversion mechanism of NIRNs and the cell death mechanism induced by photothermal therapy. Subsequently, we provided a brief conclusion of NIRNs-Lips applied in cancer photothermal therapy. Finally, we discussed a synopsis of associated challenges and future perspectives for the applications of NIRN-Lips in cancer photothermal therapy.

Cation-based approach to morphological diversity of diphenylalanine dipeptide structures

Different approaches are taken in order to examine the spontaneous arrangement processes of dipeptide structures. One of these approaches is to examine the effects of common cations on dipeptide structures' self-assembly processes. In this study, the effects of Al3+, Cu2+, Pb2+, Hg2+, Mg2+, Zn2+, Cd2+, Fe2+ and Ni2+ cations on the self-assembly processes of diphenylalanine (FF) dipeptide molecules were investigated. A detailed examination was made of the self-assembly of FF dipeptides in the presence of Hg2+, and a spherical architecture structure was shown. The morphological diversity resulting from the effects of Hg2+ cations at different concentrations on FF dipeptides was explained using Scanning Electron Microscopy (SEM), X-ray Diffraction, (XRD), and Fourier Transform Infrared Spectroscopy (FTIR) techniques. It is thought that this work will contribute to the indexing of the effects of toxic species such as Hg2+ on dipeptides, which are the smallest peptide units obtained. We think that the examination of FF dipeptides in the structures of amyloid plaques, which are thought to affect neurological disorders such as Alzheimer's and Parkinson's, will prompt further studies.

A AuNP-capped cage fluorescent biosensor based on controlled-release and cyclic enzymatic amplification for ultrasensitive detection of ATP

Gold nanodevices have attracted extensive interest in the detection of specific targets within cells. However, constructing gold sensing devices that can be activated by the simulation of remote applications remains a huge challenge. Here, we report a Au nanoparticle (AuNP)-capped cage fluorescent biosensor based on controlled-release and Exonuclease III (Exo III) assisted cyclic enzymatic amplification that can be activated by adenosine triphosphate (ATP). In the system, AuNPs were used as the building blocks to cap the pores of Au nanocages (AuNCs) loaded with Rhodamine B (RhB) molecules through the hybridization of DNA. The RhB fluorescent molecules were finally released with the help of Exo III in the presence of ATP for detection purposes. Ultimately, the biosensor leads to a wide linear ATP detection range from 1.0 × 10-9 to 1.0 × 10-7 M with a limit of detection (LOD) down to 0.88 nM. In addition, it also has good selectivity for ATP to distinguish between ATP and ATP analogues such as cytidine triphosphate (CTP), guanosine triphosphate (GTP), and uridine triphosphate (UTP). Therefore, as a convenient and sensitive biosensor, it is expected to be widely used in the biomedical field.

Plasmonically Modulated Gold Nanostructures for Photothermal Ablation of Bacteria

With the wide utilization of antibiotics, antibiotic-resistant bacteria have been often developed more frequently to cause potential global catastrophic consequences. Emerging photothermal ablation has been attracting extensive research interest for quick/effective eradication of pathogenic bacteria from contaminated surroundings and infected body. In this field, anisotropic gold nanostructures with tunable size/morphologies have been demonstrated to exhibit their outstanding photothermal performance through strong plasmonic absorption of near-infrared (NIR) light, efficient light to heat conversion, and easy surface modification for targeting bacteria. To this end, this review first introduces thermal treatment of infectious diseases followed by photothermal therapy via heat generation on NIR-absorbing gold nanostructures. Then, the usual synthesis and spectral features of diversified gold nanostructures and composites are systematically overviewed with the emphasis on the importance of size, shape, and composition to achieve strong plasmonic absorption in NIR region. Further, the innovated photothermal applications of gold nanostructures are comprehensively demonstrated to combat against bacterial infections, and some constructive suggestions are also discussed to improve photothermal technologies for practical applications.

A pH-controlled one-pot synthesis of gold nanostars by using a zwitterionic protein hydrolysate (gelatin): an enhanced radiosensitization of cancer cells

One-pot green synthesis of gold nanoparticles of desired shapes is developed by using FDA approved and economic GRAS materials. The gold nanoparticles exhibit radio-sensitization in A549 cells with star shaped nanoparticles showing maximum efficacy.

Microfluidic Synthesis of Hybrid TiO2-Anisotropic Gold Nanoparticles with Visible and Near-Infrared Activity

Anisotropic gold nanoparticles (AuNPs), with their unique physical and optical properties, are emerging as smart and key nanomaterials and are being exploited in many crucial fields. To further improve their range of action, anisotropic AuNPs have been coupled with semiconductors, mainly TiO₂ (titania), receiving great interest as powerful platforms both in biomedicine and in catalytic applications. Such hybrid nanoparticles show new properties that arise from the synergic action of the components and rely on NP size, morphology, and arrangement. Therefore, continuous advances in design and fabrication of new hybrid titania@gold NPs (TiO₂@AuNPs) are urgent and highly desirable. Here, we propose an effective protocol to produce multibranched AuNPs covered by a controlled TiO₂ thin layer, exploiting a one-pot microfluidic process. The proposed method allows the in-flow and reliable synthesis of titania-functionalized-anisotropic gold nanoparticles by avoiding the use of toxic surfactants and controlling the titania shell formation. TiO₂@AuNPs have been fully characterized in terms of morphology, stability, and biocompatibility, and their activity in photocatalysis has been tested and verified.

Liposomal nanotheranostics for multimode targeted in vivo bioimaging and near-infrared light mediated cancer therapy

Developing a nanotheranostic agent with better image resolution and high accumulation into solid tumor microenvironment is a challenging task. Herein, we established a light mediated phototriggered strategy for enhanced tumor accumulation of nanohybrids. A multifunctional liposome based nanotheranostics loaded with gold nanoparticles (AuNPs) and emissive graphene quantum dots (GQDs) were engineered named as NFGL. Further, doxorubicin hydrochloride was encapsulated in NFGL to exhibit phototriggered chemotherapy and functionalized with folic acid targeting ligands. Encapsulated agents showed imaging bimodality for in vivo tumor diagnosis due to their high contrast and emissive nature. Targeted NFGL nanohybrids demonstrated near infrared light (NIR, 750 nm) mediated tumor reduction because of generated heat and Reactive Oxygen Species (ROS). Moreover, NFGL nanohybrids exhibited remarkable ROS scavenging ability as compared to GQDs loaded liposomes validated by antitumor study. Hence, this approach and engineered system could open new direction for targeted imaging and cancer therapy.

Glycol chitosan in situ coating on PLGA nanoparticle curtails extraneous paclitaxel precipitates and imparts protein corona independent hemocompatibility

Poly (lactide-co-glycolide) (PLGA) nanoparticles surface functionalized with water soluble glycol chitosan (GC) and carboxymethyl chitosan (CMC) has been studied for their drug (Paclitaxel and Doxorubicin) loading, yield, cellular uptake, serum protein adsorption and hemocompatibility. It was observed that Paclitaxel (Ptxl) phase out as Extraneous Ptxl Precipitates (EPP) (>25 %) in case of uncoated and CMC coated low molecular weight (LMW) PLGA nanoparticles (PNPs). The EPP formation was significantly reduced to ∼5 % with GC coating as it enhanced LMW PLGA precipitation and yield predominantly spherical polymeric nanoparticles towards better encapsulation of Ptxl and thus uniform intracellular drug distribution. Interestingly, protein corona analysis showed cmcPNPs and gcPNPs to be distinct from each other in associating mainly with serum proteins of molecular weight < 30 kDa and >30 kDa respectively. While CMC functionalization showed >10 % hemolysis, at similar concentration GC coating was found to provide superior hemocompatibility even in the absence of protein corona.

Seedless synthetic branched gold nanoshells for chemo-thermal antitumor therapy

Gold nanomaterials (GNMs) are used in photothermal therapy due to their superior optical properties and excellent biocompatibility. However, the complex preparation process involving seed-mediated growth limits further clinical applications of GNMs. Herein, a novel one-pot approach to rapidly prepare liposome-based branched gold nanoshells (BGNS) as an antitumor drug nanocarrier is reported. This efficient seedless synthesis realized tunable absorption peaks of BGNS through controlling the concentration of the Au precursor solution, obtaining high absorbance in the near-infrared (NIR) window to achieve a superior photothermal effect. Hyperthermia during NIR laser irradiation can ablate the tumor and trigger drug release to achieve combined treatment. After laser irradiation, the nanocarriers disintegrated into individual gold nanoparticles (size: about 8 nm), which can be metabolized by the kidneys. Cell experiments in vitro and experiments involving mice with tumors have confirmed that the nanodrugs have strong antitumor effects. Such a flexible method provides a universal approach for rapidly preparing liposome-based gold nanoshells, which have the potential for large-scale preparation for further clinical applications.

Toward greener methods of producing branched metal nanostructures

This review highlights the use of biogenic resources (i.e., plant extracts, microorganisms, and biomolecules) as green reagents for the production of technologically promising branched metal nanomaterials.

Preparation of graphene oxide-graphene quantum dots hybrid and its application in cancer theranostics

Currently, an enormous amount of cancer research based on two-dimensional nano-graphene oxide (GO), as well as zero-dimensional graphene quantum dots (GQDs), is being carried out in the fields of therapeutics and diagnostics. However, the exploration of their hybrid "functional" nanomaterials in the theranostic system is still rare. In the current study, a stable complex of GO and GQDs was formed by an electrostatic layer-by-layer assembly via a polyethylene imine bridge (GO-PEI-GQDs). Furthermore, we compared separate mono-equivalents of the GO-PEI-GQDs complex - GO and GQDs, in terms of cell imaging (diagnostics), photothermal, and oxidative stress response in breast cancer cells (MDA-MB-231). GO-PEI-GQDs showed an excellent photothermal response (44-49 °C) upon 808 nm laser (0.5 W cm^-2) exposure for 5 min at a concentration up to 50 μg/mL. We report new synergistic properties of GO-PEI-GQDs such as stable fluorescence imaging and enhanced photothermal and cytotoxic activities on cancer cells. Composite materials made up of GO and GQDs combining diverse properties help to study 2D-0D heterosystems and improve specific therapeutic systems in theranostics.

Current multifunctional albumin-based nanoplatforms for cancer multi-mode therapy

Albumin has been widely applied for rational design of drug delivery complexes as natural carriers in cancer therapy due to its distinct advantages of biocompatibility, abundance, low toxicity and versatile property. Hence, various types of multifunctional albumin-based nanoplatforms (MAlb-NPs) that adopt multiple imaging and therapeutic techniques have been developed for cancer diagnosis and treatment. Stimuli-responsive release, including reduction-sensitive, pH-responsive, concentration-dependent and photodynamic-triggered, is important to achieve low-toxicity cancer therapy. Several types of imaging techniques can synergistically improve the effectiveness of cancer therapy. Therefore, combinational theranostic is considered to be a prospective strategy to improve treatment efficiency, minimize side effects and reduce drug resistance, which has received tremendous attentions in recent years. In this review, we highlight several stimuli-responsive albumin nanoplatforms for combinational theranostic.

Gold nanostructures as cancer theranostic probe: promises and hurdles

Gold nanostructures (GNSts) have emerged as substitute for conventional contrast agents in imaging techniques and therapeutic probes due to their tunable surface plasmon resonance and optical properties in near-infrared region. Thus GNSts provide platform for the amalgamation of diagnosis and treatment (theranostics) into a single molecule for a more precise treatment. Hence, the article talks about the application of GNSts in imaging techniques and provide a holistic view on differently shaped GNSts in cancer theranostics. However, with promises GNSts also face various hurdles for their use as theranostic probe which are primarily associated with toxicity. Finally, the article attempts to discuss the challenges faced by GNSts and the way ahead that need to be traversed to place them in nanomedicine.

The effect of nanoencapsulation of ICG on two-photon bioimaging

Multiphoton imaging, a highly effective diagnostic technique, has recently gained widespread attention for early-stage cancer detection. Tremendous efforts have been dedicated to explore various types of exogenous contrast agents for improved signal-to-noise ratio of multiphoton imaging. Indocyanine green (ICG), the only U. S. FDA approved near-infrared chromophore, has been recently used as an exogenous contrast agent for two-photon bioimaging. Despite its great potential applications in clinical settings, the conventional delivery method of ICG has limited applications due to its poor cellular uptake and optical stability in its free form. Herein, we report the effect of nanoencapsulation of ICG on two-photon bioimaging. For this study, ICG was encapsulated within poly-l-arginine (PLA) based nanoparticles for the first time. These nanoparticles were found to be biocompatible and biodegradable as the major constituents were salts and PLA. These nanoparticles were spherical with a mean diameter of ∼61 nm and exhibit higher photostability than free ICG. Additionally, nanoencapsulated ICG treated cells show enhanced contrast for two-photon bioimaging in comparison with its free form. In summary, nanoencapsulated ICG could serve as an exogenous chromophore for multiphoton imaging, which shows excellent delivery efficacy.

ICG-PLA NPs were synthesized for multiphoton bioimaging. The ICG-PLA NPs were more efficiently taken up by the cells and improved the photostability of the ICG. The ICG-PLA NPs incubated cells display superior contrast in multiphoton imaging.

Gold-nanobranched-shell based drug vehicles with ultrahigh photothermal efficiency for chemo-photothermal therapy

Development of combined chemo-photothermal nanoplatform is of great interest for enhancing antitumor efficacy. Herein, a multifunctional drug delivery system was synthesized based on gold-nanobranched coated betulinic acid liposomes (GNBS-BA-Lips) for chemo-photothermal synergistic therapy. In this system, GNBS-BA-Lips exhibited broad near-infrared (NIR) absorption, preferable photothermal response and good photostability under NIR irradiation. Importantly, the gold-nanobranched nanostructure possessed high photothermal conversion efficiency (η = 55.7%), and the temperature change (ΔT) reached 43.2 °C after laser irradiation for 5 min. Upon NIR irradiation, the nanocarriers apparently endowed higher cell uptake, resulting in an enhanced intracellular drug accumulation. Furthermore, the tumor growth inhibition ratio achieved from chemo-photothermal therapy of GNBS-BA-Lips was 86.9 ± 1.1%, which was higher than that of the chemotherapy or photothermal therapy alone, showing an outstanding synergistic anticancer effect. Our data suggested that the nanoplatform should be considered as a critical platform in the development of cancer multi-mode therapies.

Multistimuli-responsive drug vehicles based on gold nanoflowers for chemophotothermal synergistic cancer therapy

AIM

To design and synthesize a novel multistimuli-responsive drug vehicle based on gold nanoflowers (AuNFs) for chemophotothermal synergistic cancer therapy.

MATERIALS & METHODS

Multistimuli-responsive drug-delivery system based on doxorubicin (DOX)/polydopamine (PDA)-functionalized AuNFs (Lan-AuNFs@PDA/DOX) was prepared. The structural characteristics, photothermal properties and stimuli-responsive drug release properties of Lan-AuNFs@PDA/DOX were evaluated. Antitumor studies in vivo and in vitro were performed.

RESULTS

Lan-AuNFs@PDA/DOX exhibited uniform morphology, excellent biocompatibility and photothermal conversion efficiency, which could also respond to stimulus including near infrared light and pH to trigger on demand drug release. The excellent synergistic therapeutic efficacy was confirmed both in vitro and in vivo.

CONCLUSION

Lan-AuNFs@PDA/DOX would be a promising drug carrier, endowing a great potential for multistimuli-responsive chemophotothermal synergistic cancer therapy.

Plasmonic carbon nanohybrids for repetitive and highly localized photothermal cancer therapy

Integrating metallic and non-metallic platform for cancer nanomedicine is a challenging task and bringing together multi-functionality of two interfaces is a major hurdle for biomaterial design. Herein, NIR light responsive advanced hybrid plasmonic carbon nanomaterials are synthesized, and their properties toward repetitive and highly localized photothermal cancer therapy are well understood. Graphene oxide nanosheets having thickness of ∼2 nm are synthesized using modified Hummers' method, thereafter functionalized with biodegradable NIR light responsive gold deposited plasmonic polylactic-co-glycolic acid nanoshells (AuPLGA NS, tuned at 808 nm) and NIR dye (IR780) to examine their repetitive and localized therapeutic efficacy as well resulting side effects to nearby healthy cells. It is observed that AuPLGA NS decorated graphene oxide nanosheets (GO-AuPLGA) and IR780 loaded graphene oxide nanosheets (GO-IR780) are capable in standalone complete photothermal ablation of cancer cells within 4 min. of 808 nm NIR laser irradiation and also without the aid of any anticancer drugs. However, GO-AuPLGA having the potential for repetitive photothermal treatment of a big tumor, ablate the cancer cells in highly localized fashion, without having side effects on neighboring healthy cells.

Self-assembly synthesis of vapreotide‑gold hybrid nanoflower for photothermal antitumor activity

Based on the self-assembly properties of vapreotide acetate (Vap), one kind of novel vapreotide acetate‑gold nanoflowers (Vap-AuNFs) was fabricated for the first time by biomimetic mineralization method using Vap as a template. The Vap-AuNFs possessed anisotropic structure with a large absorption cross-section, which were face-centered cubic crystalline, exhibiting a remarkable monodisperse, narrow size (154 nm) distribution and good stability in aqueous solution. The apparent anisotropy of the gold nanostructure with high molar extinction coefficient can cause significantly higher plasmon absorption of Vap-AuNFs in the near infrared (NIR) region compared with Au nanoparticles (AuNPs), so the nanocomplex can induce remarkably enhanced photothermal conversion efficiency under NIR light irradiation. Breathtakingly, Vap-AuNFs exhibited superior biocompatibilities compared to AuNPs, as well as enhanced Hela cells lethality under NIR irradiation. This novel method was simple, low cost and green for the design and preparation of anisotropic gold nanoflowers with outstanding NIR laser-induced local hyperthermia, highlighting their potential applications in biomedical fields.

Morphological Evolution of Gold Nanoparticles into Nanodendrites Using Catechol-Grafted Polymer Templates

Morphology, dimension, size, and surface chemistry of gold nanoparticles are critically important in determining their optical, catalytic, and photothermal properties. Although many techniques have been developed to synthesize various gold nanostructures, complicated and multistep procedures are required to generate three-dimensional, dendritic gold nanostructures. Here, we present a simple method to synthesize highly branched gold nanodendrites through the well-controlled reduction of gold ions complexed with a catechol-grafted polymer. Dextran grafted with catechols guides the morphological evolution as a polymeric ligand to generate dendritic gold structures through the interconnection of the spherical gold nanoparticles. The reduction kinetics, which is critical for morphological changes, is controllable using dimethylacetamide, which can decrease the metal-ligand dissociation and gold ion diffusivity. This study suggests that mussel-inspired polymer chemistry provides a simple one-pot synthetic route to colloidal gold nanodendrites that are potentially applicable to biosensing and catalysis.

Potent Anticancer Activity with High Selectivity of a Chiral Palladium N-Heterocyclic Carbene Complex

Five enantiomeric pairs of palladium complexes of 1,2,4-triazole-derived chiral N-heterocyclic carbene ligands were investigated to probe the influence of chirality on the compound's anticancer activity. Although no chirality-related influence was observed for any of the enantiomeric pair, strong anticancer activity was seen for a particular pair, (1S,2S,5R)-1c and (1R,2R,5S)-1c, which was significantly more active than the benchmark drug cisplatin for human breast cancer cells, MCF-7 (ca. 24-27-fold), and human cervical cancer cells, HeLa (ca. three- to fourfold). Broadening its scope of application, (1R,2R,5S)-1c also exhibited antiproliferative activity against lung cancer (A549), skin cancer (B16F10), and multidrug-resistant mammary tumor (EMT6/AR1) cell lines. Interestingly, (1R,2R,5S)-1c displayed 8- and 16-fold stronger antiproliferative activity toward B16F10 and MCF-7 relative to their respective noncancerous counterparts, L929 (fibroblast skin cells) and MCF10A (epithelial breast cells), thereby upholding the potential of these complexes for further development as anticancer agents. (1R,2R,5S)-1c inhibited tumor-cell proliferation by blocking the cells at the G2 phase. (1R,2R,5S)-1c caused DNA damage in MCF-7 cells, leading to mitochondrial reactive oxygen species production and subsequently cell death. We also present evidence indicating that (1R,2R,5S)-1c induced p53-dependent programmed cell death in MCF-7 cells.

Strategies for Preparing Albumin-based Nanoparticles for Multifunctional Bioimaging and Drug Delivery

Biosafety is the primary concern in clinical translation of nanomedicine. As an intrinsic ingredient of human blood without immunogenicity and encouraged by its successful clinical application in Abraxane, albumin has been regarded as a promising material to produce nanoparticles for bioimaging and drug delivery. The strategies for synthesizing albumin-based nanoparticles could be generally categorized into five classes: template, nanocarrier, scaffold, stabilizer and albumin-polymer conjugate. This review introduces approaches utilizing albumin in the preparation of nanoparticles and thereby provides scientists with knowledge of goal-driven design on albumin-based nanomedicine.

Gold nanoshell coated thermo-pH dual responsive liposomes for resveratrol delivery and chemo-photothermal synergistic cancer therapy

Stimuli-responsive drug delivery and release have a great significance in cancer therapy. Herein, a multifunctional responsive drug carrier was designed and developed by loading resveratrol (Res) in chitosan (CTS) modified liposomes, and coated by gold nanoshells (GNS@CTS@Res-lips). The resultant GNS@CTS@Res-lips possess broad near-infrared (NIR) absorbance, high capability, stability, and also high photothermal conversion ability for efficient photothermal therapy (PTT) applications. In addition, the GNS@CTS@Res-lips exhibit the on-demand pH/photothermal-sensitive drug release, and a high loading capacity of Res. Under NIR laser irradiation, the drug delivery system could significantly enhance the cellular uptake of drugs. More importantly, compared to the single chemotherapy or PTT, the carriers with NIR irradiation displayed a higher therapeutic effect for HeLa cells. Therefore, the GNS@CTS@Res-lips with a combination of chemotherapy and PTT will show great potential for application in cancer therapy.

Core-Shell Gold Nanorod@Metal-Organic Framework Nanoprobes for Multimodality Diagnosis of Glioma

One of the most significant challenges in the diagnosis of brain cancer is efficient in vivo imaging using nontoxic nanoprobes. Core-shell gold nanorod@MIL-88(Fe) nanostars are successfully constructed as triple-modality imaging (computed tomography/magnetic-resonance imaging/photoacoustic imaging) nanoprobes that show low cytotoxicity, high contrast, high penetration depth, and high spatial resolution for accurate and noninvasive imaging and diagnosis of gliomas.

NIR light-triggered shrinkable thermoresponsive PNVCL nanoshells for cancer theranostics

NIR light-responsive gold coated shrinkable thermoresponsive nanoshells as preliminary step to ablate large and deep-seated tumors using combined chemo-photothermal therapy.

Biologically inspired self-assembly of bacitracin-based platinum nanoparticles with anti-tumor effects

The green synthesis of bacitracin-based platinum nanoparticles with excellent antitumor efficacyin vitroandin vivo.

TEMPO-Oxidized Nanocellulose Fiber-Directed Stable Aqueous Suspension of Plasmonic Flower-like Silver Nanoconstructs for Ultra-Trace Detection of Analytes

The synthesis of shape-tuned silver (Ag) nanostructures with high plasmon characteristics has become of significant importance in in vitro diagnostic applications. Herein, we report a simple aqueous synthetic route using 2,2,6,6-tetramethylpiperidine-1-oxyl-oxidized nanocellulose fibers (T-NCFs) and trisodium citrate (TSC) that results in anisotropically grown flower-like Ag nanoconstructs (AgNFs). A detailed investigation of the concentration and sequence of the addition of reactants in the formation of these anisotropic Ag structures is presented. Our experimental results show that the mechanism underlying the formation of AgNFs is facilitated by the synergistic action of T-NCFs and TSC on the directional growth of Ag nuclei during the primary stage, which later develop into a flower-like structure by the ripening of larger particles consuming smaller Ag particles. As a result the final structure comprises flower-like morphology over which several smaller Ag particles (of size <10 nm) are adhered. The aqueous AgNF colloid exhibits high stability (ζ = -69.4 mV) and long shelf-life at neutral pH (>4 months) by the efficient capping action of T-NCFs. Further, an as-synthesized nanoconstructs shows excellent surface-enhanced Raman scattering activity, which enables ultrasensitive detection of p-aminothiophenol with a concentration down to 10 aM (10^-17 M) in a reproducible way. This biosupported synthesis of stable aqueous colloids of AgNF may find potential applications as a biomedical sensing platform for the trace level detection of analyte molecules.

Albumin stabilized gold nanostars: a biocompatible nanoplatform for SERS, CT imaging and photothermal therapy of cancer

Albumin stabilization of gold nanostars, which demonstrate high stability, biocompatibility, superior CT contrast, SERS and photothermal cytotoxicity towards cancer cells.