Copper sulphide based heterogeneous nanoplatforms for multimodal therapy and imaging of cancer: Recent advances and toxicological perspectives

Chiral ligands and photothermal synergistic effects of inorganic nanoparticles for bacteria-killing

As the drawbacks of antibiotics in treating bacterial infections emerged, physical methods such as near-infrared-activated (NIR-activated) bacterial killing, have attracted great interests for their advantages of no resistance, short action time and few side effects. In this manuscript, NIR-activated bacteria-killing performance of chiral copper sulphide nanoparticles (L-/d-CuS NPs) was investigated using linearly polarized light (LPL) and circularly polarized light (CPL) as illumination sources, respectively. Chiral CuS NPs showed enhanced NIR-activated bacteria-killing effect compared with achiral CuS NPs under the same conditions. Moreover, these chiral CuS NPs showed obvious chirality-related antibacterial effect: the bacterial killing was more efficient under CPL activation, and L- and d-CuS NPs had higher antibacterial efficiency under left circularly polarized light (LCPL) and right circularly polarized light (RCPL), respectively. The possible mechanism of bacteria-killing performance for chiral CuS NPs was discussed in detailed. Photothermal bacteria-killing tests of chiral CuS NPs "sealed" in polydimethylsiloxane (PDMS) demonstrated the individual influence of photothermal effect. These observations in this paper could provide ideas for the potential applications of chiral nanostructures with enhanced photothermal effect in efficient bacterial killing.

A critical review on metal-organic frameworks (MOFs) based nanomaterials for biomedical applications: Designing, recent trends, challenges, and prospects

Nanomaterials (NMs) have garnered significant attention in recent decades due to their versatile applications in a wide range of fields. Thanks to their tiny size, enhanced surface modifications, impressive volume-to-surface area ratio, magnetic properties, and customized optical dispersion. NMs experienced an incredible upsurge in biomedical applications including diagnostics, therapeutics, and drug delivery. This minireview will focus on notable examples of NMs that tackle important issues, demonstrating various aspects such as their design, synthesis, morphology, classification, and use in cutting-edge applications. Furthermore, we have classified and outlined the distinctive characteristics of the advanced NMs as nanoscale particles and hybrid NMs. Meanwhile, we emphasize the incredible potential of metal-organic frameworks (MOFs), a highly versatile group of NMs. These MOFs have gained recognition as promising candidates for a wide range of bio-applications, including bioimaging, biosensing, antiviral therapy, anticancer therapy, nanomedicines, theranostics, immunotherapy, photodynamic therapy, photothermal therapy, gene therapy, and drug delivery. Although advanced NMs have shown great potential in the biomedical field, their use in clinical applications is still limited by issues such as stability, cytotoxicity, biocompatibility, and health concerns. This review article provides a thorough analysis offering valuable insights for researchers investigating to explore new design, development, and expansion opportunities. Remarkably, we ponder the prospects of NMs and nanocomposites in conjunction with current technology.

Advances of Photothermal Agents with Fluorescence Imaging/Enhancement Ability in the Field of Photothermal Therapy and Diagnosis

Photothermal therapy (PTT) is an effective cancer treatment method. Due to its easy focusing and tunability of the irradiation light, direct and accurate local treatment can be performed in a noninvasive manner by PTT. This treatment strategy requires the use of photothermal agents to convert light energy into heat energy, thereby achieving local heating and triggering biochemical processes to kill tumor cells. As a key factor in PTT, the photothermal conversion ability of photothermal agents directly determines the efficacy of PTT. In addition, photothermal agents generally have photothermal imaging (PTI) and photoacoustic imaging (PAI) functions, which can not only guide the optimization of irradiation conditions but also achieve the integration of disease diagnosis. If the photothermal agents have function of fluorescence imaging (FLI) or fluorescence enhancement, they can not only further improve the accuracy in disease diagnosis but also accurately determine the tumor location through multimodal imaging for corresponding treatment. In this paper, we summarize recent advances in photothermal agents with FLI or fluorescence enhancement functions for PTT and tumor diagnosis. According to the different recognition sites, the application of specific targeting photothermal agents is introduced. Finally, limitations and challenges of photothermal agents with fluorescence imaging/enhancement in the field of PTT and tumor diagnosis are prospected.

Engineering of copper sulfide mediated by phototherapy performance

Copper sulfide based phototherapy, including photothermal therapy and photodynamic therapy, is an emerging minimally invasive treatment of tumor, which the light was converted to heat or reactive oxygen to kill the tumor cells. Compared with conventional chemotherapy and radiation therapy, Cu2-x S based phototherapy is more efficient and has fewer side effects. However, considering the dose-dependent toxicity of Cu2-x S, the performance of Cu2-x S based phototherapy still cannot meet the requirement of the clinical application to now. To overcome this limitation, engineering of Cu2-x S to improve the phototherapy performance by increasing light absorption has attracted extensive attention. For better guidance of Cu2-x S engineering, we outline the currently engineering method being explored, including (1) structural engineering, (2) compositional engineering, (3) functional engineering, and (4) performance engineering. Also, the relationship between the engineering method and phototherapy performance was discussed in this review. In addition, the further development of Cu2-x S based phototherapy is prospected, including smart materials based phototherapy, phototherapy induced immune microenvironment modulation et al. This review will provide new ideas and opportunities for engineering of Cu2-x S with better phototherapy performance. This article is categorized under: Diagnostic Tools > In Vivo Nanodiagnostics and Imaging Therapeutic Approaches and Drug Discovery > Nanomedicine for Oncologic Disease.

Nanotheranostics: Molecular Diagnostics and Nanotherapeutic Evaluation by Photoacoustic/Ultrasound Imaging in Small Animals

Nanotheranostics is a rapidly developing field that integrates nanotechnology, diagnostics, and therapy to provide novel methods for imaging and treating wide categories of diseases. Targeted nanotheranostics offers a platform for the precise delivery of theranostic agents, and their therapeutic outcomes are monitored in real-time. Presently, in vivo magnetic resonance imaging, fluorescence imaging, ultrasound imaging, and photoacoustic imaging (PAI), etc. are noninvasive imaging techniques that are preclinically available for the imaging and tracking of therapeutic outcomes in small animals. Additionally, preclinical imaging is essential for drug development, phenotyping, and understanding disease stage progression and its associated mechanisms. Small animal ultrasound imaging is a rapidly developing imaging technique for theranostics applications due to its merits of being nonionizing, real-time, portable, and able to penetrate deep tissues. Recently, different types of ultrasound contrast agents have been explored, such as microbubbles, echogenic exosomes, gas-vesicles, and nanoparticles-based contrast agents. Moreover, an optical image obtained through photoacoustic imaging is a noninvasive imaging technique that creates ultrasonic waves when pulsed laser light is used to expose an object and creates a picture of the tissue's distribution of light energy absorption on the object. Contrast agents for photoacoustic imaging may be endogenous (hemoglobin, melanin, and DNA/RNA) or exogenous (dyes and nanomaterials-based contrast agents). The integration of nanotheranostics with photoacoustic and ultrasound imaging allows simultaneous imaging and treatment of diseases in small animals, which provides essential information about the drug response and the disease progression. In this review, we have covered various endogenous and exogenous contrast agents for ultrasound and photoacoustic imaging. Additionally, we have discussed various drug delivery systems integrated with contrast agents for theranostic application. Further, we have briefly discussed the current challenges associated with ultrasound and photoacoustic imaging.

Developing a Hetero-Trinuclear Erbium(III)-Copper(II) Complex Based on Apoferritin: Targeted Photoacoustic Imaging and Multimodality Therapy of Tumor

For the integration of targeted diagnosis and treatment of tumor, we innovatively designed and synthesized a single-molecule hetero-multinuclear Er(III)-Cu(II) complex (ErCu2) and then constructed an ErCu2@apoferritin (AFt) nanoparticle (NP) delivery system. ErCu2 and ErCu2@AFt NPs not only provided an evident photoacoustic imaging (PAI) signal of the tumor but also effectively inhibited tumor growth by integrating photothermal therapy, chemotherapy, and immunotherapy. ErCu2@AFt NPs improved the targeting ability and decreased the systemic toxicity of ErCu2 in vivo. Furthermore, we confirmed that ErCu2 and ErCu2@AFt NPs inhibited tumor growth by inducing apoptosis and autophagy of tumor cells and activating the immune system. The study not only provides a novel strategy to develop therapeutic metal agents but also reveals their potential for targeted accurate diagnosis and multimodality therapy of cancer.

In vivo synergistic tumor therapies based on copper sulfide photothermal therapeutic nanoplatforms

Tumor cells may be eliminated by increasing their temperature. This is achieved via photothermal therapy (PTT) by penetrating the tumor tissue with near-infrared light and converting light energy into heat using photothermal agents. Copper sulfide nanoparticles (CuS NPs) are commonly used as PTAs in PTT. In this review, we aimed to discuss the synergism between tumor PTT with CuS NPs and other therapies such as chemotherapy, radiotherapy, dynamic therapies (photodynamic, chemodynamic, and sonodynamic therapy), immunotherapy, gene therapy, gas therapy, and magnetic hyperthermia. Furthermore, we summarized the results obtained with a combination of two treatments and at least two therapies, with PTT as one of the included therapies. Finally, we summarized the benefits and drawbacks of various therapeutic options and state of the art CuS-based PTT and provided future directions for such therapies.

An inorganic-organic-polymeric nanovehicle for targeting delivery of doxorubicin: Rational assembly, pH-stimulus release, and dual hyperthermia/chemotherapy of hepatocellular carcinoma

Efficiently synergistic therapy of hepatocellular carcinoma (HCC) by chemotherapeutic drug and photothermal agent remains a considerable challenge. Here, we report a nanodrug that integrates specific hepatoma-targeted delivery, pH-triggered drug release, and cooperative photothermal-chemotherapy function. By grafting the easily self-assembled CuS@polydopamine (CuS@PDA) nanocapsulation with polyacrylic acid (PAA), an inorganic-organic-polymeric hybrid nanovehicle was developed as a dual photothermal agent and carrier for loading antitumor drug-doxorubicin (DOX) through electrostatic adsorption and chemical linking antibody against GPC3 commonly overexpressed in HCC, resulting in the nanodrug, CuS@PDA/PAA/DOX/GPC3. The multifunctional nanovehicle had excellent biocompatibility, stability, and high photothermal conversion efficiency, due to the rationally designed binary CuS@PDA photothermal agent. The 72-h accumulative drug release in pH 5.5 tumor microenvironment can reach up to 84%, far higher than 15% measured in pH 7.4 condition. Notably, in contrast to the merely 20% survival rate of H9c2 and HL-7702 cells exposed to free DOX, their viabilities in the nanodrug circumstance can maintain 54% and 66%, respectively, suggesting the abated toxicity to the normal cell lines. When exposed to the hepatoma-targeting nanodrug, the viability of HepG2 cells was found to be 36%, which further drastically declined to 10% plus 808-nm NIR irradiation. Moreover, the nanodrug is potent to cause tumor ablation in HCC-modeled mice, and the therapeutic efficacy can be greatly enhanced under NIR stimulus. Histology analyses reveal that the nanodrug can effectively alleviate the chemical damage to heart and liver, as compared to free DOX. This work thus offers a facile strategy for design of targeting anti-HCC nanodrug toward combined photothermal-chemotherapy.

Core-shell structured hollow copper sulfide@metal-organic framework for magnetic resonance imaging guided photothermal therapy in second near-infrared biological window

Multifunctional core-shell hybrids formed by integration of metal-organic framework (MOF) and functional materials have attracted extensive attention as promising theranostic nanoplatforms due to their combined novel properties and enhanced therapeutic efficacy. Recently, the second near-infrared (NIR-II, 1000-1700 nm) laser-induced photothermal therapy (PTT) as compared to the NIR-I(700-950 nm) laser-induced PTT has displayed improved therapeutic effects owing to its merits that include deeper tissue penetration and increased maximum permissible exposure. Herein, a novel core-shell hollow copper sulfide@metal-organic framework (HCuS@MIL-100) has been successfully fabricated by a layer-by-layer technique for the first time and their collective theranostic effects are investigated in vitro and in vivo. In this platform, the inner HCuS was applied as the NIR-II photothermal agent with excellent NIR-II absorption feature, leading to impressive photothermal effects under irradiation by 1064 nm light. With MIL-100 as the shell, HCuS@MIL-100 not only displayed optimal biocompatibility but also presented superior T2 magnetic resonance imaging (MRI) ability. In the current study multifunctional hollow core-shell HCuS@MIL-100 are fabricated for the MRI-guided PTT. This study also offers a facile and effective strategy for the development of novel theranostic platforms with high efficiency through the integration of MOFs and functional materials.

Recent advances in near-infrared-II hollow nanoplatforms for photothermal-based cancer treatment

Near-infrared-II (NIR-II, 1000–1700 nm) light-triggered photothermal therapy (PTT) has been regarded as a promising candidate for cancer treatment, but PTT alone often fails to achieve satisfactory curative outcomes. Hollow nanoplatforms prove to be attractive in the biomedical field owing to the merits including good biocompatibility, intrinsic physical-chemical nature and unique hollow structures, etc. On one hand, hollow nanoplatforms themselves can be NIR-II photothermal agents (PTAs), the cavities of which are able to carry diverse therapeutic units to realize multi-modal therapies. On the other hand, NIR-II PTAs are capable of decorating on the surface to combine with the functions of components encapsulated inside the hollow nanoplatforms for synergistic cancer treatment. Notably, PTAs generally can serve as good photoacoustic imaging (PAI) contrast agents (CAs), which means such kind of hollow nanoplatforms are also expected to be multifunctional all-in-one nanotheranostics. In this review, the recent advances of NIR-II hollow nanoplatforms for single-modal PTT, dual-modal PTT/photodynamic therapy (PDT), PTT/chemotherapy, PTT/catalytic therapy and PTT/gas therapy as well as multi-modal PTT/chemodynamic therapy (CDT)/chemotherapy, PTT/chemo/gene therapy and PTT/PDT/CDT/starvation therapy (ST)/immunotherapy are summarized for the first time. Before these, the typical synthetic strategies for hollow structures are presented, and lastly, potential challenges and perspectives related to these novel paradigms for future research and clinical translation are discussed.

Multifunctional nanotheranostics for near infrared optical imaging-guided treatment of brain tumors

Malignant brain tumors, a heterogeneous group of primary and metastatic neoplasms in the central nervous system (CNS), are notorious for their highly invasive and devastating characteristics, dismal prognosis and low survival rate. Recently, near-infrared (NIR) optical imaging modalities including fluorescence imaging (FLI) and photoacoustic imaging (PAI) have displayed bright prospect in innovation of brain tumor diagnoses, due to their merits, like noninvasiveness, high spatiotemporal resolution, good sensitivity and large penetration depth. Importantly, these imaging techniques have been widely used to vividly guide diverse brain tumor therapies in a real-time manner with high accuracy and efficiency. Herein, we provide a systematic summary of the state-of-the-art NIR contrast agents (CAs) for brain tumors single-modal imaging (e.g., FLI and PAI), dual-modal imaging (e.g., FLI/PAI, FLI/magnetic resonance imaging (MRI) and PAI/MRI) and triple-modal imaging (e.g., MRI/FLI/PAI and MRI/PAI/computed tomography (CT) imaging). In addition, we update the most recent progress on the NIR optical imaging-guided therapies, like single-modal (e.g., photothermal therapy (PTT), chemotherapy, surgery, photodynamic therapy (PDT), gene therapy and gas therapy), dual-modal (e.g., PTT/chemotherapy, PTT/surgery, PTT/PDT, PDT/chemotherapy, PTT/chemodynamic therapy (CDT) and PTT/gene therapy) and triple-modal (e.g., PTT/PDT/chemotherapy, PTT/PDT/surgery, PTT/PDT/gene therapy and PTT/gene/chemotherapy). Finally, we discuss the opportunities and challenges of the CAs and nanotheranostics for future clinic translation.

Copper-based nanomaterials for cancer theranostics

Copper-based nanomaterials (Cu-based NMs) with favorable biocompatibility and unique properties have attracted the attention of many biomedical researchers. Cu-based NMs are one of the most widely studied materials in cancer treatment. In recent years, great progress has been made in the field of biomedicine, especially in the treatment and diagnosis of tumors. This review begins with the classification of Cu-based NMs and the recent synthetic strategies of Cu-based NMs. Then, according to the abundant and special properties of Cu-based NMs, their application in biomedicine is summarized in detail. For biomedical imaging, such as photoacoustic imaging, positron emission tomography imaging, and multimodal imaging based on Cu-based NMs are summarized, as well as strategies to improve the diagnostic effectiveness. Moreover, a series of unique structures and functions as well as the underlying property activity relationship of Cu-based NMs were shown to highlight their promising therapeutic performance. Cu-based NMs have been widely used in monotherapies, such as photothermal therapy (PTT) and chemodynamic therapy (CDT). Moreover, the sophisticated design in composition, structure, and surface fabrication of Cu-based NMs can endow these NMs with more modalities in cancer diagnosis and therapy. To further improve the efficiency of cancer treatment, combined therapy based on Cu-based NMs was introduced in detail. Finally, the challenges, critical factors, and future prospects for the clinical translation of Cu-based NMs as multifunctional theranostic agents were also considered and discussed. The aim of this review is to provide a better understanding and key consideration for the rational design of this increasingly important new paradigm of Cu-based NMs as theranostic agents. This article is categorized under: Therapeutic Approaches and Drug Discovery > Nanomedicine for Oncologic Disease Diagnostic Tools > In Vivo Nanodiagnostics and Imaging.

Advancements in cell membrane camouflaged nanoparticles: A bioinspired platform for cancer therapy

The idea of employing natural cell membranes as a coating medium for nanoparticles (NPs) endows man-made vectors with natural capabilities and benefits. In addition to retaining the physicochemical characteristics of the NPs, the biomimetic NPs also have the functionality of source cell membranes. It has emerged as a promising approach to enhancing the properties of NPs for drug delivery, immune evasion, imaging, cancer-targeting, and phototherapy sensitivity. Several studies have been reported with a multitude of approaches to reengineering the surface of NPs using biological membranes. Owing to their low immunogenicity and intriguing biomimetic properties, cell-membrane-based biohybrid delivery systems have recently gained a lot of interest as therapeutic delivery systems. This review summarises different kinds of biomimetic NPs reported so far, their fabrication aspects, and their application in the biomedical field. Finally, it briefs on the latest advances available in this biohybrid concept.

Copper-induced tumor cell death mechanisms and antitumor theragnostic applications of copper complexes

Recent studies found that unbalanced copper homeostasis affect tumor growth, causing irreversible damage. Copper can induce multiple forms of cell death, including apoptosis and autophagy, through various mechanisms, including reactive oxygen species accumulation, proteasome inhibition, and antiangiogenesis. Hence, copper in vivo has attracted tremendous attention and is in the research spotlight in the field of tumor treatment. This review first highlights three typical forms of copper's antitumor mechanisms. Then, the development of diverse biomaterials and nanotechnology allowing copper to be fabricated into diverse structures to realize its theragnostic action is discussed. Novel copper complexes and their clinical applications are subsequently described.

Silica-Supported Assemblage of CuII Ions with Carbon Dots for Self-Boosting and Glutathione-Induced ROS Generation

The present work introduces coordinative binding of CuII ions with both amino-functionalized silica nanoparticles (SNs) and green-emitting carbon dots (CDs) as the pregrequisite for the CuII-assisted self-assembly of the CDs at the surface of the SNs. The produced composite SNs exhibit stable in time stimuli-responsive green fluorescence derived from the CuII-assisted assemblage of CDs. The fluorescence response of the composite SNs is sensitive to the complex formation with glutathione (GSH), enabling them to detect it with the lower limit of detection of 0.15 μM. The spin-trap-facilitated electron spin resonance technique indicated that the composite SNs are capable of self-boosting generation of ROS due to CuII→CuI reduction by carbon in low oxidation states as a part of the CDs. The intensity of the ESR signals is enhanced under the heating to 38 °C. The intensity is suppressed at the GSH concentration of 0.35 mM but is enhanced at 1.0 mM of glutathione, while it is suppressed once more at the highest intracellular concentration level of GSH (10 mM). These tendencies reveal the concentrations optimal for the scavenger or reductive potential of GSH. Flow cytometry and fluorescence and confocal microscopy methods revealed efficient cell internalization of SNs-NH2-CuII-CDs comparable with that of “free” CDs.

Chiral CuS nanoparticles and their photothermal properties

Chiral CuS NPs were prepared through a ligand-exchange process and CPL-controlled photothermal performance was realized.

Dual-Modified Cu2S with MoS2 and Reduced Graphene Oxides as Efficient Photocatalysts for H2 Evolution Reaction

Noble metal-free cocatalysts have drawn great interest in accelerating the catalytic reactions of metal chalcogenide semiconductor photocatalyst. In particular, great efforts have been made on modifying a semiconductor with dual cocatalysts, which show synergistic effect of a fast transfer of exciton and energy simultaneously. Herein, we report the dual-modified Cu2S with MoS2 and reduced graphene oxides (Cu2S-MoS2/rGO). The in situ growth of Cu2S nanoparticles in the presence of MoS2/rGO resulted in high density of nanoscale interfacial contacts among Cu2S nanoparticles, MoS2, and rGO, which is beneficial for reducing the photogenerated electrons’ and holes’ recombination. The Cu2S-MoS2/rGO system also demonstrated stable photocatalytic activity for H2 evolution reaction for the long term.

Diagnostic Radionuclides Labeled on Biomimetic Nanoparticles for Enhanced Follow-Up Photothermal Therapy of Cancer

Imaging-guided local therapy is the most effective strategy to treat primary cancers in patients. However, the local therapeutic effect should be further improved under the premise of absence of induction of additional side effects. It would be meaningful to analyze the potential assistance of nuclear imaging to the follow-up treatments. In this study,cancer-targeted copper sulfide nanoparticles with ^99m Tc labeling (^99m Tc-M-CuS-PEG) are prepared using-cancer cell membranes as a synthesis reactor and applied for the potential single-photon emission computed tomography/photoacoustic imaging-guided and ^99m Tc-amplified photothermal therapy of cancer. Owing to the homologous targeting capability of the cancer cell membrane, M-CuS-PEG selectively accumulates in homologous tumor sites. After labeling with ^99m Tc, M-CuS-PEG with a high near-infrared light absorbance can realize bimodal imaging-guided photothermal therapy of cancer. Furthermore, the labeled ^99m Tc significantly enhances the cell uptake of M-CuS-PEG by inducing G2/M arrest of the cell cycle, further improving the photothermal antitumor effect, which is positively correlated with endocytosis of the photothermal conversion reagent. Therefore, a novel cancer-targeted theranostic nanoplatform is developed and it is revealed that the labeled ^99m Tc can not only guide but also amplify the subsequent therapy of cancer, providing a conceptual strategy for cancer theranostics with a high biosafety.

Liposomes as Versatile Platform for Cancer Theranostics: Therapy, Bio-imaging, and Toxicological Aspects

Liposomes are nano-sized formulations having the benefits of site-specificity, biocompatibility, and biodegradability, which make them useful for the therapy and diagnosis of major diseases like cancer. In this review, various synthetic strategies of liposomes and their biomedical application in special concern to cancer are discussed. In context to the biomedical application, this article gives a detailed insight into subcellular targeted therapy and several therapeutic modifications like immunotherapy, receptor-based therapy, phototherapy, and combination therapy. The review also describes the liposome-based imaging platforms and the toxicity associated with liposomes. Owing to a significant amount of benefits of this carrier system, several products have been approved to be launched in the market and several others have already been marketed for clinical use.

Subcellular imaging and diagnosis of cancer using engineered nanoparticles

The advances in the synthesis of nanoparticles with engineered properties are reported to have profound applications in oncological disease detection via optical and multimodal imaging and therapy. Among various nanoparticle-assisted imaging techniques, engineered fluorescent nanoparticles show great promise from high contrast images and localized therapeutic applications. Of all the fluorescent nanoparticles available, the gold nanoparticles, carbon dots, and upconversion nanoparticles are emerging recently as the most promising candidates for diagnosis, treatment, and cancer monitoring. This review addresses the recent progress in engineering the properties of these emerging nanoparticles and their application for cancer diagnosis and therapy. In addition, the potential of these particles for subcellular imaging is also reviewed here.

A facile route toward hydrophilic plasmonic copper selenide nanocrystals: new perspectives for SEIRA applications

Development of versatile and efficient plasmonic nanoprobes for detection of (bio)molecules in an ultrasmall concentration, when applied as substrates in surface-enhanced infrared (SEIRA) spectroscopy.