Rational design of a comprehensive cancer therapy platform using temperature-sensitive polymer grafted hollow gold nanospheres: simultaneous chemo/photothermal/photodynamic therapy triggered by a 650 nm laser with enhanced anti-tumor efficacy

Novel Drug Delivery Systems: An Important Direction for Drug Innovation Research and Development

The escalating demand for enhanced therapeutic efficacy and reduced adverse effects in the pharmaceutical domain has catalyzed a new frontier of innovation and research in the field of pharmacy: novel drug delivery systems. These systems are designed to address the limitations of conventional drug administration, such as abbreviated half-life, inadequate targeting, low solubility, and bioavailability. As the disciplines of pharmacy, materials science, and biomedicine continue to advance and converge, the development of efficient and safe drug delivery systems, including biopharmaceutical formulations, has garnered significant attention both domestically and internationally. This article presents an overview of the latest advancements in drug delivery systems, categorized into four primary areas: carrier-based and coupling-based targeted drug delivery systems, intelligent drug delivery systems, and drug delivery devices, based on their main objectives and methodologies. Additionally, it critically analyzes the technological bottlenecks, current research challenges, and future trends in the application of novel drug delivery systems.

Recent advances in photodynamic therapy combined with chemotherapy for cervical cancer: a systematic review

INTRODUCTION

Despite the evidence that photodynamic therapy (PDT) associated with chemotherapy presents great potential to overcome the limitations of monotherapy, little is known about the current status of this combination against cervical cancer. This systematic review aimed to address the currently available advances in combining PDT and chemotherapy in different research models and clinical trials of cervical cancer.

METHODS

We conducted a systematic review based on PRISMA Statement and Open Science Framework review protocol using PubMed, Web of Science, Embase, Scopus, LILACS, and Cochrane databases. We selected original articles focusing on 'Uterine Cervical Neoplasms' and 'Photochemotherapy and Chemotherapy' published in the last 10 years. The risk of bias in the studies was assessed using the CONSORT and SYRCLE tools.

RESULTS

Twenty-three original articles were included, focusing on HeLa cells, derived from endocervical adenocarcinoma and on combinations of several chemotherapeutics. Most of the combinations used modern drug delivery systems for improved simultaneous delivery and presented promising results with increased cytotoxicity compared to monotherapy.

CONCLUSION

Despite the scarcity of animal studies and the absence of clinical studies, the combination of chemotherapy with PDT presents a potential option for cervical cancer therapy requiring additional studies.

OSF REGISTRATION

https://doi.org/10.17605/OSF.IO/WPHN5 [Figure: see text].

Synthesis, Characterization and Biosafety Evaluation of Hollow Gold Nanospheres

OBJECTIVES

In order to assess the biosafety of HAuNS using zebrafish models and the cancer cell lines HepG2, HEK293, and A549, this study prepared HAuNS in a variety of sizes and alterations.

METHODS

By oxidizing cobalt nanoparticles encased in gold shells, HAuNS were created. In the meantime, PEG- and PEI-coated HAuNS were created. The diameters of the HAuNS that were produced were 30~40 nm, 50~60 nm, and 70~80 nm. MTT assay was used to assess the toxicity of HAuNS on HepG2, HEK293, and A549 cells. For the investigation of their toxicities, HAuNS (50~60 nm) of various concentrations were incubated with zebrafish embryos. Then, cell death was determined using acridine orange staining.

RESULTS

In a cell line model, it was demonstrated that purified HAuNS exhibit lower toxicity than unpurified HAuNS. Meanwhile, it was discovered that surface-modified HAuNS was less hazardous than unmodified HAuNS. Unpurified HAuNS (50.60 nm) exposure to embryos caused deformity and increased mortality. Moreover, embryos exposed to HAuNS displayed an increase in cell death, showing that HAuNS can put zebrafish under physiological stress.

CONCLUSION

The possible toxicity of HAuNS is now more understood thanks to this investigation. The details could improve our comprehension of the nanotoxicity of medication delivery systems. Comparing HAuNS (50~60 nm) to the other two particle sizes, its toxicity was quite low. Compared to unpurified HAuNS, purified HAuNS displayed less toxicity. Comparing PEI-HAuNS and HAuNS to PEG-HAuNS, cytotoxicity was found to be lower. Our data support the use of pure HAuNS, HAuNS-PEG, and HAuNS (50~60 nm) as possible photothermal conductors when seen as a whole.

Conjugated Polymer Nanoparticles for Tumor Theranostics

Water-dispersible conjugated polymer nanoparticles (CPNs) have demonstrated great capabilities in biological applications, such as in vitro cell/subcellular imaging and biosensing, or in vivo tissue imaging and disease treatment. In this review, we summarized the recent advances of CPNs used for tumor imaging and treatment during the past five years. CPNs with different structures, which have been applied to in vivo solid tumor imaging (fluorescence, photoacoustic, and dual-modal) and treatment (phototherapy, drug carriers, and synergistic therapy), are discussed in detail. We also demonstrated the potential of CPNs as cancer theranostic nanoplatforms. Finally, we discussed current challenges and outlooks in this field.

Recent Development of MOF-Based Photothermal Agent for Tumor Ablation

Metal-organic frameworks (MOFs) are 3D-architecture compounds of metal ions and organic molecules with sufficient and permanent porosity, showing great potential as a versatile platform to load various functional moieties to endow the hybrid materials with specific applications. Currently, a variety of photothermal nanometals have been embedded into organic ligands for integrating the unique photothermal effects with the merits of MOFs to improve their performances for cancer therapy. In this review, we have summarized a series of novel MOF-based photothermal materials for this unique therapeutic modality against tumors from three main aspects according to their chemical compositions and structures, i) metal-doped MOF, ii) organic-doped MOF, and iii) polymer-coated MOF. In addition, we have summarized the latest developments and characteristics of MOF-based photothermal agents, such as good biocompatibility, low toxicity, and responsive photothermal conversion without destroying the structure of hybrid photothermal agent. At last, we addressed the future perspectives of MOF-based photothermal agent in the field of phototherapy.

NIR-II Fluorescent Activatable Drug Delivery Nanoplatform for Cancer-Targeted Combined Photodynamic and Chemotherapy

Nanotheranostics with integrated imaging functions can help monitor nanoparticle accumulation in tumors, thus achieving synergism and higher therapeutic accuracy in cancer therapy. However, it remains challenging to monitor the release of therapeutic drugs in real time from a nanoparticulate drug delivery system (nano-DDS) in the body. Herein, we developed a nano-DDS for fluorescence imaging in the second near-infrared window (NIR-II) region, which can be used for monitoring the responsive release of drugs and cancer-targeted combined photodynamic and chemotherapy. There is a linear correlation between the cumulative release of the drug and the NIR-II fluorescence intensity. Moreover, hyaluronidase/glutathione dual-response RGD-SS-DOX/Ce6@HA-IR-1061 (RSSDCHI) exhibited a higher tumor-to-normal-tissue ratio in NIR-II fluorescence imaging and enhanced antitumor efficacy in vivo. This makes it possible to visualize drug release at the cellular level by the nanocomposites and to predict the treatment effect according to the NIR-II fluorescence intensity in the tumor site, serving as a promising nanoplatform for precision nanomedicine.

A review of advanced nanoformulations in phototherapy for cancer therapeutics

Phototherapy has the potential to play a greater role in oncology. Phototherapy converts light energy into either chemical energy or thermal energy, which eventually destroys cancer cells after a series of biological reactions. With nanotechnology applications in cancer therapeutics, it has become possible to prepare smart drug carriers with multifunctional properties at the nanoscale level. These nanocarriers may be able to deliver the drug molecules to the target site more efficiently in the form of nanoparticles. Several intrinsic and extrinsic properties of these nanocarriers help target the tumor cells exclusively, and by utilizing these features, drug molecules can be delivered to the tumor cells specifically, which results in high tumor uptake and better therapeutic effects ultimately. Nanocarriers can also be designed to carry different drugs together to provide a platform for combination therapy like chemo-photodynamic therapy and chemo-photodynamic-photothermal therapy. In combination therapy, co-delivery of all different drugs is crucial to obtain their synergistic effects, and with the help of nanocarriers, it is possible to co-deliver these drugs by loading them together onto the nanocarriers.

Ultralow-intensity near infrared light synchronously activated collaborative chemo/photothermal/photodynamic therapy

Although combined chemotherapy (Chemo), photothermal (PTT) and photodynamic (PDT) in cancer therapy has drawn significant attention due to its superior anticancer ability, the required high intensity of irradiation results in serious photo-toxicity to healthy neighboring cells, and thus limits its biomedical applications. Herein, we developed an ultralow-intensity near infrared (NIR) light synchronously activated collaborative Chemo/PTT/PDT nanoplatform. The nanoplatform is composed of a highly emissive upconversion (UC) core, chlorin e6 (Ce6) photosensitizer and the anticancer drug doxorubicin hydrochloride (DOX) co-loaded in a mesoporous silica (MS) shell, and polyethylene glycol-modified graphene (PGO) acts as both the photothermal reagent and smart switch for promoted drug release. Upon 808 nm NIR light exposure with ultralow intensity (0.25 W cm-2), which is below the maximum permissible exposure (MPE, 0.33 W cm-2) for skin, the mild hyperpyrexia of PGO induced both cancer cell irreversible death for PTT and greatly promoted drug release for enhanced Chemo. On the other hand, the upconverted 660 nm light from UC activated Ce6 to generate reactive oxygen species for PDT, while the upconverted 540 nm light from UC could be employed for visualizing the treatment process. The in vitro and in vivo anticancer experiments demonstrate that the ultralow-intensity NIR light synchronously activated Chemo/PTT/PDT nanoplatform exhibits remarkable therapeutic efficacy with minimal photodamage.

Multifunctional theranostic agents based on prussian blue nanoparticles for tumor targeted and MRI-guided photodynamic/photothermal combined treatment

The independence of photodynamic or photothermal modality create difficulties in the success of tumor therapy. In this current study, a multifunctional nanotheranostic agent of PDE-Ce6-HA was developed for tumor targeted and MRI-guided photodynamic/photothermal combined therapy (PDT/PTT). For this purpose, the near-infrared-absorbing nanoparticles of prussian blue were coated with polydopamine and successively conjugated with chlorin e6 (Ce6) for reactive oxygen species (ROS) generation. The resultant nanoparticles, denoted as PDE-Ce6, were then modified with hyaluronic acid (HA) through electrostatic interaction to yield the final therapeutic agent of PDE-Ce6-HA NPs. PDE-Ce6-HA NPs not only exhibited high colloid stability, good biocompatibility and suitable transverse relaxation rate (0.54 mM^-1 s^-1), but also high photothermal conversion efficiency (40.4%) and excellent ROS generation efficiency under NIR light irradiation. The confocal microscopy images demonstrated a selective uptake of PDE-Ce6-HA by CD44 overexpressed HeLa cells via HA-mediated endocytosis. Meanwhile, in vitro anti-cancer evaluation verified the significant photodynamic and photothermal combined effects of PDE-Ce6-HA on cancer cells. Moreover, PDE-Ce6-HA led to an increase of T₁-MRI contrast in tumor site. Furthermore, in vivo anti-tumor evaluation proved that the PDE-Ce6-HA under both 808 and 670 nm laser showed significantly high tumor growth inhibition effects compared with individual PTT or PDT. Hence, PDE-Ce6-HA is applicable in tumor targeted and MRI-guided photodynamic/photothermal combined treatment.

Yolk-Shell Structured Au Nanostar@Metal-Organic Framework for Synergistic Chemo-photothermal Therapy in the Second Near-Infrared Window

Light-sensitive yolk-shell nanoparticles (YSNs) as remote-controlled and stimuli-responsive theranostic platforms provide an attractive method for synergistic cancer therapy. Herein, a kind of novel stimuli-responsive multifunctional YSNs has been successfully constructed by integrating star-shaped gold (Au star) nanoparticles as the second near-infrared (NIR-II) photothermal yolks and biodegradable crystalline zeolitic imidazolate framework-8 (ZIF-8) as the shells. In this platform, a chemotherapeutic drug (doxorubicin hydrochloride, DOX) was encapsulated into the cavity, which can show the behavior of controlled release due to the degradation process of ZIF-8 in the mildly acidic tumor microenvironment. Upon the 1064 nm (NIR-II biowindow) laser irradiation, gold nanostar@ZIF-8 (Au@MOF) nanoparticles exhibited outstanding synergistic anticancer effect based on their photothermal and promoted cargo release properties. Moreover, the strong NIR region absorbance endows the Au@MOF of NIR thermal imaging and photoacoustic (PA) imaging properties. This work contributes to design a stimuli-responsive "all-in-one" nanocarrier that realizes bimodal imaging diagnosis and chemo-photothermal synergistic therapy.

Monodispersed CuSe Sensitized Covalent Organic Framework Photosensitizer with an Enhanced Photodynamic and Photothermal Effect for Cancer Therapy

Attributed to its simplicity, noninvasive features, and excellent therapeutic effect, phototherapy has recently received considerable interest. The combination of photothermal therapy (PTT) and photodynamic therapy (PDT) holds great promise in the treatment of tumors, and in order to achieve satisfactory antitumor efficacy, suitable photosensitizers are a prerequisite. In this paper, highly monodispersed covalent organic framework (COF) nanoparticles were first prepared by a mild solution-phase synthesis method at room temperature. The as-synthesized nonporphyrin containing COF nanoparticle was employed as a novel photosensitizer for PDT, which exhibited an excellent photodynamic effect under 650 or 808 nm laser irradiation. Then, CuSe nanoparticles, an ideal photothermal agent, were successfully conjugated with COF to form a dual functional photosensitizer for phototherapy. The resultant COF-CuSe platform possesses an excellent synergistic photothermal and photodynamic effect. The in vitro and in vivo experiments indicated an enhanced therapeutic effect on killing cancer cells and inhibiting the tumor growth. This work demonstrates the great potential of nonporphyrin containing COF as a photosensitizer for photodynamic cancer therapy and provides a facile and efficient approach to construct COF-based multifunctional theranostic agents for cancer diagnosis and treatment by combining COFs with other functional materials.

Inorganic nanomaterials for chemo/photothermal therapy: a promising horizon on effective cancer treatment

During the last few decades, nanotechnology has established many essential applications in the biomedical field and in particular for cancer therapy. Not only can nanodelivery systems address the shortcomings of conventional chemotherapy such as limited stability, non-specific biodistribution and targeting, poor water solubility, low therapeutic indices, and severe toxic side effects, but some of them can also provide simultaneous combination of therapies and diagnostics. Among the various therapies, the combination of chemo- and photothermal therapy (CT-PTT) has demonstrated synergistic therapeutic efficacies with minimal side effects in several preclinical studies. In this regard, inorganic nanostructures have been of special interest for CT-PTT, owing to their high thermal conversion efficiency, application in bio-imaging, versatility, and ease of synthesis and surface modification. In addition to being used as the first type of CT-PTT agents, they also include the most novel CT-PTT systems as the potentials of new inorganic nanomaterials are being more and more discovered. Considering the variety of inorganic nanostructures introduced for CT-PTT applications, enormous effort is needed to perform translational research on the most promising nanomaterials and to comprehensively evaluate the potentials of newly introduced ones in preclinical studies. This review provides an overview of most novel strategies used to employ inorganic nanostructures for cancer CT-PTT as well as cancer imaging and discusses current challenges and future perspectives in this area.

A chloroplast-inspired nanoplatform for targeting cancer and synergistic photodynamic/photothermal therapy

A bioinspired nanoplatform composed of Cu(ii)-chlorophyll–hyaluronic acid nanoparticles (Cu(ii)Chl–HA NPs) was developed for targeting cancer and combined photodynamic/photothermal therapy.

Near-infrared nanoparticles based on indocyanine green-conjugated albumin: a versatile platform for imaging-guided synergistic tumor chemo-phototherapy with temperature-responsive drug release

BACKGROUND

The aim of this study was to develop a multifunctional theranostic agent based on BSA nanoparticles (NPs), which loaded artemisinin (ART) and co-conjugated with indocyanine green (ICG) and arginine-glycine-aspartic acid (RGD) peptide (RGD-indocyanine green-Bovine Serum Albumin-artemisinin [IBA] NPs).

MATERIALS AND METHODS

The physicochemical parameters of RGD-IBA NPs were character-ized in terms of the particle size, zeta potential, morphology, entrapment efficiency, drug loading, in vitro release behavior, photothermal and photodynamic effect, and in vitro anticancer ability. In vivo fluorescence and thermal imaging as well as antitumor studies were also evaluated.

RESULTS

The tumor chemotherapeutic effects of ART and the ability of fluorescence imaging, hyperthermia generation and reactive oxygen species production of ICG and tumor-targeting RGD were integrated to achieve RGD-IBA NPs for imaging-guided tumor-targeted chemotherapy/photothermal/photodynamic therapy (chemo-phototherapy). The RGD-IBA NPs showed enhanced physiological stability and photo-stability compared with free ART and ICG. In addition, they were temperature-responsive; their sizes increased with increasing temperature between 25°C and 55°C, thereby leading to drug release upon the irradiation with near infrared (NIR) laser. In vivo fluorescence images of tumor-bearing mice showed that the RGD-IBA NPs could highly and passively reach the targeted tumor region with maximum accumulation at 24 hours post-intravenous injection. The in vitro and in vivo results demonstrated that the RGD-IBA NPs not only have good biocompatibility, but also are highly efficient tumor synergistic chemo-phototherapeutic agents.

CONCLUSION

Through this study, it was found that RGD-IBA NPs could potentially be a very promising tumor theranostic agent.

Selective Growth Synthesis of Ternary Janus Nanoparticles for Imaging-Guided Synergistic Chemo- and Photothermal Therapy in the Second NIR Window

Multifunctional therapeutic agents in the second near-infrared (NIR-II) window have attracted wide attention on account of their synergetic properties for effective cancer therapy. Here, we construct a selective growth strategy for the first time to fabricate ternary Janus nanoparticles (JNPs) containing hemispherical MnO₂ at one side and Au core covered with CuS shell at opposite side. The obtained ternary JNPs are further modified with poly(ethylene glycol)thiol to enhance the stability and biocompatibility (designated as PEG-CuS-Au-MnO₂ ternary JNPs). The MnO₂ domain with mesoporous structures can serve as hydrophobic drug carriers and magnetic resonance (MR) imaging contrast agents. Meanwhile, the Au segment is used for X-ray computed tomography (CT) imaging. Moreover, the PEG-CuS-Au-MnO₂ ternary JNPs can conduct hyperthermia at 1064 nm in NIR-II window to ablate tumors in deep tissue, which is ascribed to the localized surface plasmon resonance coupling effect of the Au core and CuS domain. All of the results reveal that PEG-CuS-Au-MnO₂ ternary JNPs not only exhibit pre-eminent CT/MR imaging capabilities, but also provide high chemo-photothermal antitumor efficacy under the guidance of CT/MR imaging. Taking together, the PEG-CuS-Au-MnO₂ ternary JNPs can be regarded as a prospective therapeutic nanoplatform for dual-modal imaging-guided synergistic chemo-photothermal cancer therapy in the NIR-II window.

Multi-functional bismuth-doped bioglasses: combining bioactivity and photothermal response for bone tumor treatment and tissue repair

Treatment of large bone defects derived from bone tumor surgery is typically performed in multiple separate operations, such as hyperthermia to extinguish residual malignant cells or implanting bioactive materials to initiate apatite remineralization for tissue repair; it is very challenging to combine these functions into a material. Herein, we report the first photothermal (PT) effect in bismuth (Bi)-doped glasses. On the basis of this discovery, we have developed a new type of Bi-doped bioactive glass that integrates both functions, thus reducing the number of treatment cycles. We demonstrate that Bi-doped bioglasses (BGs) provide high PT efficiency, potentially facilitating photoinduced hyperthermia and bioactivity to allow bone tissue remineralization. The PT effect of Bi-doped BGs can be effectively controlled by managing radiative and non-radiative processes of the active Bi species by quenching photoluminescence (PL) or depolymerizing glass networks. In vitro studies demonstrate that such glasses are biocompatible to tumor and normal cells and that they can promote osteogenic cell proliferation, differentiation, and mineralization. Upon illumination with near-infrared (NIR) light, the bioglass (BG) can efficiently kill bone tumor cells, as demonstrated via in vitro and in vivo experiments. This indicates excellent potential for the integration of multiple functions within the new materials, which will aid in the development and application of novel biomaterials.

Polymer-Based Nanocarriers for Co-Delivery and Combination of Diverse Therapies against Cancers

Cancer gives rise to an enormous number of deaths worldwide nowadays. Therefore, it is in urgent need to develop new therapies, among which combined therapies including photothermal therapy (PTT) and chemotherapy (CHT) using polymer-based nanocarriers have attracted enormous interest due to the significantly enhanced efficacy and great progress has been made so far. The preparation of such nanocarriers is a comprehensive task involving the cooperation of nanomaterial science and biomedicine science. In this review, we try to introduce and analyze the structure, preparation and synergistic therapeutic effect of various polymer-based nanocarriers composed of anti-tumor drugs, nano-sized photothermal materials and other possible parts. Our effort may bring benefit to future exploration and potential applications of similar nanocarriers.

DNA decorated Cu9S5 nanoparticles as NIR light responsive drug carriers for tumor chemo–phototherapy

Recently, near-infrared (NIR) light responsive drug delivery systems have attracted much attention for tumor therapy.

Hollow polymer nanocapsules: synthesis, properties, and applications

Hollow polymer nanocapsules (HPNs) have gained tremendous interest in recent years due to their numerous desirable properties compared to their solid counterparts.

A tumor-mitochondria dual targeted aza-BODIPY-based nanotheranostic agent for multimodal imaging-guided phototherapy

Mitochondria targeted phototherapy, including photodynamic therapy (PDT) and photothermal therapy (PTT), has excelled as an effective approach among other non-specific techniques for its high selectivity, non-invasiveness and low systemic toxicity.

An efficient synergistic cancer therapy by integrating cell cycle inhibitor and photosensitizer into polydopamine nanoparticles

A novel polydopamine (PDA) based nanocomposite loaded with cell cycle inhibitor (NOC) and photosensitizer (ZnPc12⁺) was developed for efficient synergistic cancer therapy.

Single Near-Infrared Emissive Polymer Nanoparticles as Versatile Phototheranostics

Attaining consistently high performance of diagnostic and therapeutic functions in one single nanoplatform is of great significance for nanomedicine. This study demonstrates the use of donor-acceptor (D-A) structured polymer (TBT) to develop a smart "all-five-in-one" theranostic that conveniently integrates fluorescence/photoacoustic/thermal imaging and photodynamic/photothermal therapy into single nanoparticle. The prepared nanoparticles (TBTPNPs) exhibit near-infrared emission, high water solubility, excellent light resistance, good pH stability, and negligible toxicity. Additionally, the TBTPNPs exhibit an excellent singlet oxygen (1O2) quantum yield (40%) and high photothermal conversion efficiency (37.1%) under single-laser irradiation (635 nm). Apart from their two phototherapeutic modalities, fluorescence, photoacoustic signals, and thermal imaging in vivo can be simultaneously achieved because of their enhanced permeability and retention effects. This work demonstrates that the prepared TBTPNPs are "all-five-in-one" phototheranostic agents that can exhibit properties to satisfy the "one-fits-all" requirement for future phototheranostic applications. Thus, the prepared TBTPNPs can provide fundamental insights into the development of PNP-based nanoagents for cancer therapy.

Erythrocyte Membrane-Wrapped pH Sensitive Polymeric Nanoparticles for Non-Small Cell Lung Cancer Therapy

The application of nano drug delivery systems (NDDSs) may enhance the effectiveness of chemotherapeutic drugs in vivo. However, the short blood circulation time and poor drug release profile in vivo are still two problems with them. Herein, by using red blood cell membrane (RBCm) wrapping and pH sensitive technology, we prepared RBCm wrapped pH sensitive poly(l-γ-glutamylcarbocistein)-paclitaxel (PGSC-PTX) nanoparticles (PGSC-PTX@RBCm NPs), to prolong the circulation time in blood and release PTX timely and adequately in acidic tumor environment. The PGSC-PTX NPs and PGSC-PTX@RBCm NPs showed spherical morphology with average sizes about 50 and 100 nm, respectively. The cytotoxicity of PGSC-PTX@RBCm NPs was considerably decreased compared with that of PGSC-PTX NPs. PTX release from PGSC-PTX and PGSC-PTX@RBCm NPs at pH 6.5 was remarkably higher than those at pH 7.4, respectively. The PGSC-PTX@RBCm NPs exhibited remarkably decreased uptake by macrophages than PGSC-PTX NPs. The area under the curve within 72 h (AUC_0-72h) for is significantly higher than PGSC-PTX NPs. The PGSC-PTX@RBCm NPs also showed significantly stronger growth-inhibiting effect on tumor than PGSC-PTX NPs. These results indicated that PGSC-PTX@RBCm NPs have acidic drug release sensitivity, the characteristics of long circulation, and remarkable tumor growth inhibiting effect. This study may provide an effective strategy for improving the antitumor effect of NDDS.

Construction of Hierarchical Polymer Brushes on Upconversion Nanoparticles via NIR-Light-Initiated RAFT Polymerization

Photoinduced reversible addition-fragmentation chain transfer (RAFT) polymerization generally adopts high-energy ultraviolet (UV) or blue light. In combination with photoredox catalyst, the excitation light wavelength was extended to the visible and even near-infrared (NIR) region for photoinduced electron transfer RAFT polymerization. In this report, we introduce for the first time a surface NIR-light-initiated RAFT polymerization on upconversion nanoparticles (UCNPs) without adding any photocatalyst and construct a functional inorganic core/polymer shell nanohybrid for application in cancer theranostics. The multilayer core-shell UCNPs (NaYF₄:Yb/Tm@NaYbF₄:Gd@NaNdF₄:Yb@NaYF₄), with surface anchorings of chain transfer agents, can serve as efficient NIR-to-UV light transducers for initiating the RAFT polymerization. A hierarchical double block copolymer brush, consisting of poly(acrylic acid) (PAA) and poly(oligo(ethylene oxide)methacrylate-co-2-(2-methoxy-ethoxy)ethyl methacrylate) (PEG for short), was grafted from the surface in sequence. The targeting arginine-glycine-aspartic (RGD) peptide was modified at the end of the copolymer through the trithiolcarbonate end group. After loading of doxorubicin, the UCNPs@PAA-b-PEG-RGD exhibited an enhanced U87MG cancer cell uptake efficiency and cytotoxicity. Besides, the unique upconversion luminescence of the nanohybrids was used for the autofluoresence-free cell imaging and labeling. Therefore, our strategy verified that UCNPs could efficiently activate RAFT polymerization by NIR photoirradiation and construct the complex nanohybrids, exhibiting prospective biomedical applications due to the low phototoxicity and deep penetration of NIR light.

A Hollow-Structured CuS@Cu2 S@Au Nanohybrid: Synergistically Enhanced Photothermal Efficiency and Photoswitchable Targeting Effect for Cancer Theranostics

It is of great importance in drug delivery to fabricate multifunctional nanocarriers with intelligent targeting properties, for cancer diagnosis and therapy. Herein, hollow-structured CuS@Cu₂ S@Au nanoshell/satellite nanoparticles are designed and synthesized for enhanced photothermal therapy and photoswitchable targeting theranostics. The remarkably improved photothermal conversion efficiency of CuS@Cu₂ S@Au under 808 nm near-infrared (NIR) laser irradiation can be explained by the reduced bandgap and more circuit paths for electron transitions for CuS and Cu₂ S modified with Au nanoparticles, as calculated by the Vienna ab initio simulation package, based on density functional theory. By modification of thermal-isomerization RGD targeting molecules and thermally sensitive copolymer on the surface of nanoparticles, the transition of the shielded/unshielded mode of RGD (Arg-Gly-Asp) targeting molecules and shrinking of the thermally sensitive polymer by NIR photoactivation can realize a photoswitchable targeting effect. After loading an anticancer drug doxorubicin in the cavity of CuS@Cu₂ S@Au, the antitumor therapy efficacy is greatly enhanced by combining chemo- and photothermal therapy. The reported nanohybrid can also act as a photoacoustic imaging agent and an NIR thermal imaging agent for real-time imaging, which provides a versatile platform for multifunctional theranostics and stimuli-responsive targeted cancer therapy.

A new NIR-triggered doxorubicin and photosensitizer indocyanine green co-delivery system for enhanced multidrug resistant cancer treatment through simultaneous chemo/photothermal/photodynamic therapy

It is a great challenge to combat multidrug resistant (MDR) cancer effectively. To address this issue, we developed a new near-infrared (NIR) triggered chemotherapeutic agent doxorubicin (DOX) and photosensitizer indocyanine green (ICG) co-release system by aid of NIR induced photothermal effect of gold nanocages (AuNCs) and temperature sensitive phase-change property of 1-tetradecanol at its melting point of 39°C, which could simultaneously exerted chemo/photothermal/photodynamic treatment on MDR human breast cancer MCF-7/ADR cells. This nano-sized system was constructed by filling the interior of AuNCs with DOX, ICG and 1-tetradecanol, and modifying the surface with biotinylated poly (ethylene glycol) via Au-S bonds, termed as DOX/ICG@biotin-PEG-AuNC-PCM. The DOX and ICG co-release from DOX/ICG@biotin-PEG-AuNC-PCM was much faster in PBS at 40°C or under 808nm NIR irradiation at 2.5W/cm² than at 37°C (e.g. 67.27% or 80.31% vs. 5.57% of DOX, 76.08% vs. 3.83% of ICG for 20min). The flow cytometry and confocal laser scanning microscopy (CLSM) results showed, the AuNCs were taken up by MCF-7/ADR cells via endocytosis, thus enhancing DOX uptake; the biotin on AuNCs facilitated this endocytosis; NIR irradiation caused the heating of the AuNCs, triggering the DOX and ICG co-release and enhancing the distribution of DOX in nuclei, the released ICG generated ROS to take photodynamic therapy. Due to the above unique properties, DOX/ICG@biotin-PEG-AuNC-PCM exerted excellent anti-tumor effects under NIR irradiation, its IC₅₀ against MCF-7/ADR cells was very low, only 0.48µg/mL, much smaller than that of free DOX (74.51μg/mL).

STATEMENT OF SIGNIFICANCE

A new near-infrared (NIR) triggered chemotherapeutic agent doxorubicin (DOX) and photosensitizer indocyanine green (ICG) co-release system by aid of NIR induced photothermal effect of gold nanocages (AuNCs) and temperature sensitive phase-change property of 1-tetradecanol at its melting point of 39°C, was prepared, termed as DOX/ICG@biotin-PEG-AuNC-PCM, which could simultaneously exerted chemo/photothermal/photodynamic treatment on MDR human breast cancer MCF-7/ADR cells. DOX/ICG@biotin-PEG-AuNC-PCM exerted excellent anti-tumor effects under NIR irradiation, its IC₅₀ against MCF-7/ADR cells was very low, only 0.48µg/mL, much smaller than that of free DOX (74.51μg/mL).

Synthesis and Optimization of MoS2@Fe3O4-ICG/Pt(IV) Nanoflowers for MR/IR/PA Bioimaging and Combined PTT/PDT/Chemotherapy Triggered by 808 nm Laser

Elaborately designed biocompatible nanoplatforms simultaneously achieving multimodal bioimaging and therapeutic functions are highly desirable for modern biomedical applications. Herein, uniform MoS2 nanoflowers with a broad size range of 80-180 nm have been synthesized through a facile, controllable, and scalable hydrothermal method. The strong absorbance of MoS2 nanoflowers at 808 nm imparts them with high efficiency and stability of photothermal conversion. Then a novel multifunctional composite of MoS2@Fe3O4-ICG/Pt(IV) (labeled as Mo@Fe-ICG/Pt) is designed by covalently grafting Fe3O4 nanoparticles with polyethylenimine (PEI) functionalized MoS2, and then loading indocyanine green molecules (ICG, photosensitizers) and platinum (IV) prodrugs (labeled as Pt(IV) prodrugs) on the surface of MoS2@Fe3O4. The resulting Mo@Fe-ICG/Pt nanocomposites can achieve excellent magnetic resonance/infrared thermal/photoacoustic trimodal biomaging as well as remarkably enhanced antitumor efficacy of combined photothermal therapy, photodynamic therapy, and chemotherapy triggered by a single 808 nm NIR laser, thus leading to an ideal nanoplatform for cancer diagnosis and treatment in future.

Doxorubicin-Loaded Photosensitizer-Core pH-Responsive Copolymer Nanocarriers for Combining Photodynamic Therapy and Chemotherapy

Photodynamic therapy (PDT) is an emerging method for the treatment of cancer. Combination of PDT and chemotherapy is a hot topic though the two therapies could not simultaneously exert their perfect effect in vivo. Here we report a doxorubicin-loaded photosensitizer-core pH-responsive copolymer nanocarrier with high tumor targeting and anticancer effects due to integration of PDT with chemotherapy. The pH-responsive photosensitizer-core four-armed star-shaped copolymer, [methoxy-poly(ethylene glycol)-poly(2-(N,N-diethylamino)ethyl methacrylate)-poly(ε-caprolactone)]₄-zinc β-tetra-(4-carboxyl benzyloxyl)phthalocyanine (PDCZP), was prepared, which was a molecular spherical nanocarrier in aqueous media. The carriers changed from small at high pH to large at low pH (51, 105, and 342 nm at pH 7.4, 6.5, and 5.0, respectively) and the zeta potential gradually increased (7.15, 16.2, and 26.1 mV at the above pH, respectively). PDCZP had a longer emission wavelength (max. 677 nm) than the parent photosensitizer, favoring light penetration through biological tissues. The singlet oxygen (¹O₂) quantum yield of PDCZP was 0.41. Doxorubicin (DOX) showed rapid release from PDCZP in the acidic media. More importantly, the drug-loaded nanocarriers showed the better in vitro and in vivo anticancer effects under lighting on MCF-7, SW480 cells and HepG2 cells and the murine hepatocellular carcinoma H₂₂ models than the other groups. PDCZP showed a high tumor targeting effect based on the enhanced permeation and retention effect and its small size. The photosensitizer-core nanocarrier is a promising photodynamic nanocarrier for integrating other therapies.

Functional hollow nanostructures for imaging and phototherapy of tumors

Various types of inorganic and organic phototherapeutic hollow nanostructures for the imaging and treatment of tumors are reviewed.

Dual-pH-sensitivity and tumour targeting core–shell particles for intracellular drug delivery

The principal problem in the area of drug delivery is achieving better selectivity and controllability.

Raman tags: Novel optical probes for intracellular sensing and imaging

Optical labels are needed for probing specific target molecules in complex biological systems. As a newly emerging category of tags for molecular imaging in live cells, the Raman label attracts much attention because of the rich information obtained from targeted and untargeted molecules by detecting molecular vibrations. Here, we list three types of Raman probes based on different mechanisms: Surface Enhanced Raman Scattering (SERS) probes, bioorthogonal Raman probes, and Resonance Raman (RR) probes. We review how these Raman probes work for detecting and imaging proteins, nucleic acids, lipids, and other biomolecules in vitro, within cells, or in vivo. We also summarize recent noteworthy studies, expound on the construction of every type of Raman probe and operating principle, sum up in tables typically targeting molecules for specific binding, and provide merits, drawbacks, and future prospects for the three Raman probes.

Gold nanorod@silica-carbon dots as multifunctional phototheranostics for fluorescence and photoacoustic imaging-guided synergistic photodynamic/photothermal therapy

Phototheranostics, which is the application of light in the diagnostic imaging and therapy of cancer, has shown great promise for multimodal cancer imaging and effective therapy. Herein, we developed multifunctional gold nanorod@silica-carbon dots (GNR@SiO2-CDs) as a phototheranostic agent by incorporating carbon dots (CDs) with gold nanorods (GNRs), using SiO2 as a scaffold. In GNR@SiO2-CDs, the GNRs act as both photoacoustic (PA) imaging and photothermal therapy (PTT) agents, and the CDs serve as fluorescence (FL) imaging and photodynamic therapy (PDT) agents. The introduction of SiO2 not only improves the chemical stability of the GNRs and CDs in the physiological environment but also prevents the absolute quenching of the fluorescence of the CDs by GNRs. These collective properties make GNR@SiO2-CDs a novel phototheranostic agent, in which high sensitivity and good spatial resolution of FL/PA imaging can be achieved to guide PDT/PTT treatments through i.v. administration. The combination of PDT and PTT proved to be more efficient in killing cancer cells compared to PDT or PTT alone under a low dose of laser irradiation (≤0.5 W cm(-2)). Furthermore, GNR@SiO2-CDs could be cleared out from the body of mice, indicating the low toxicity of this phototheranostic agent. Our work highlights the potential of using GNRs and CDs as novel phototheranostic agents for multifunctional cancer therapies.