Low‐Magnetization Magnetic Microcapsules: A Synergistic Theranostic Platform for Remote Cancer Cells Therapy and Imaging

Multifunctional magnetic microcapsules (MMCs) for the combined cancer cells hyperthermia and chemotherapy in addition to MR imaging are successfully developed. A classical layer‐by‐layer technique of oppositely charged polyelectrolytes (poly(allylamine hydrochloride) (PAH) and poly(4‐styrene sulfonate sodium) (PSS)) is used as it affords great controllability over the preparation together with enhanced loading of the chemotherapeutic drug (doxorubicin, DOX) in the microcapsules. Superparamagnetic iron oxide (SPIOs) nanoparticles are layered in the system to afford MMC1 (one SPIOs layer) and MMC2 (two SPIOs layers). Most interestingly, MMC1 and MMC2 show efficient hyperthermia cell death and controlled DOX release although their magnetic saturation value falls below 2.5 emu g^?1, which is lower than the 7–22 emu g^?1 reported to be the minimum value needed for biomedical applications. Moreover, MMCs are pH responsive where a pH 5.5 (often reported for cancer cells) combined with hyperthermia increases DOX release predictably. Both systems prove viable when used as T2 contrast agents for MR imaging in HeLa cells with high biocompatibility. Thus, MMCs hold a great promise to be used commercially as a theranostic platform as they are controllably prepared, reproducibly enhanced, and serve as drug delivery, hyperthermia, and MRI contrast agents at the same time.     

A Multifunctional Nanocrystalline CaF2:Tm,Yb@mSiO2 System for Dual‐Triggered and Optically Monitored Doxorubicin Delivery

Daunting challenges in investigating the controlled release of drugs in complicated intracellular microenvironments demand the development of stimuli‐responsive drug delivery systems. Here, a nanoparticle system, CaF₂:Tm,Yb@mSiO₂, made of a mesoporous silica (mSiO₂) nanosphere with CaF₂:Tm,Yb upconversion nanoparticles (UCNPs) is developed, filling its mesopores and with its surface‐modified with polyacrylic acid for binding the anticancer drug molecules (doxorubicin, DOX). The unique design of CaF₂:Tm,Yb@mSiO₂ enables us to trigger the drug release by two mechanisms. One is the pH‐triggered mechanism, where drug molecules are preferentially released from the nanoparticles at acidic conditions unique for the intracellular environment of cancer cells compared to normal cells. Another is the 808 nm near infrared (NIR)‐triggered mechanism, where 808 nm NIR induces the heating of the nanoparticles to weaken the electrostatic interaction between drug molecules and nanoparticles. In addition, luminescence resonance energy transfer occurs from the UCNPs (the energy donor) to the DOX drug (the energy acceptor) in the presence of 980 nm NIR irradiation, allowing us to monitor the drug release by detecting the vanishing blue emission from the UCNPs. This study demonstrates a new multifunctional nanosystem for dual‐triggered and optically monitored drug delivery, which will facilitate the rational design of personalized cancer therapy.     

Multifunctional antitumor magnetite/chitosan-<Emphasis Type="SmallCaps">l</Emphasis>-glutamic acid (core/shell) nanocomposites

The development of anticancer drug delivery systems based on biodegradable nanoparticles has been intended to maximize the localization of chemotherapy agents within tumor interstitium, along with negligible drug distribution into healthy tissues. Interestingly, passive and active drug targeting strategies to cancer have led to improved nanomedicines with great tumor specificity and efficient chemotherapy effect. One of the most promising areas in the formulation of such nanoplatforms is the engineering of magnetically responsive nanoparticles. In this way, we have followed a chemical modification method for the synthesis of magnetite/chitosan-l-glutamic acid (core/shell) nanostructures. These magnetic nanocomposites (average size ≈340 nm) exhibited multifunctional properties based on its capability to load the antitumor drug doxorubicin (along with an adequate sustained release) and its potential for hyperthermia applications. Compared to drug surface adsorption, doxorubicin entrapment into the nanocomposites matrix yielded a higher drug loading and a slower drug release profile. Heating characteristics of the magnetic nanocomposites were investigated in a high-frequency alternating magnetic gradient: a stable maximum temperature of 46 °C was successfully achieved within 40 min. To our knowledge, this is the first time that such kind of stimuli-sensitive nanoformulation with very important properties (i.e., magnetic targeting capabilities, hyperthermia, high drug loading, and little burst drug release) has been formulated for combined antitumor therapy against cancer.     

Monodisperse Polypyrrole Nanoparticles Prepared via γ‐Ray Radiolysis of Water: An Efficient Near‐Infrared Photothermal Agent for Cancer Therapy

Biosafe nanoparticles with strong near‐infrared (NIR) light photothermal conversion effect can bring effective hyperthermia as one of the promising approaches in cancer therapy. In this work, a new facile and green preparation method of polypyrrole (PPy) nanoparticles based on ⁶⁰Co γ‐ray radiation on a simple air‐saturated strong acidic aqueous solution of pyrrole (pH ≤ 1) is studied. According to the MCAP‐FACSIMILE simulation on the concentrations of the radiolysis products of water at the presence of H⁺ and O₂, the main strong oxidative radiolysis products · OH and H₂O₂ rapidly induce the polymerization of pyrrole. The size of the prepared PPy nanoparticles is about several tens of nanometers and can be controlled by the pH, the concentration of the stabilizer poly(vinyl alcohol), and the absorbed dose rate (the amount of energy absorbed per unit mass of the irradiated material within per unit of time). The PPy nanoparticles show rapid and remarkable NIR (808 nm) photothermal conversion efficiency up to 40.1% in water. Furthermore, the in vitro and in vivo experiments confirm that the prepared PPy nanoparticles exhibit enough strong NIR photothermal effect in tumor cells (4T1 and HeLa) and show a promising prospect as the NIR photothermal agent for the future cancer therapy.     

Temperature and Redox Dual‐Responsive Biodegradable Nanogels for Optimizing Antitumor Drug Delivery

The strategy to efficiently deliver antitumor drugs via nanocarriers to targeted tumor sites and achieve controllable drug release is attracting great research interest in cancer therapy. In this study, a novel type of disulfide‐bonded poly(vinylcaprolactam) (PVCL)‐based nanogels with tunable volume phase transition temperature and excellent redox‐labile property are prepared. The nanogels are hydrophilic and swell at 37 °C, whereas under hyperthermia (e.g., 41 °C), the nanogels undergo sharp hydrophilic/hydrophobic transition and volume collapse, which enhances the cellular uptake and drug release. The incorporation of disulfide bond linkers endows the nanogels with an excellent disassembly property in reducing environments, which greatly facilitates drug release in tumor cells. Nanogels loaded with doxorubicin (DOX) (DOX‐NGs) (DOX‐NGs) are stable in physiological conditions with low drug leakage (15% in 48 h), while burst release of DOX (92% in 12 h) can be achieved in the presence of 10 × 10^?3 m glutathione and under hyperthermia. The DOX‐NGs possess improved cell killing efficiency under hyperthermia (IC₅₀ decreased from 1.58 μg mL^?1 under normothermia to 0.5 μg mL^?1). Further, the DOX‐NGs show a pronounced tumor inhibition rate of 46.6% compared with free DOX, demonstrating that this new dual‐responsive nanogels have great potential as drug delivery carriers for cancer therapy in vivo.     

Functionalized Biomimetic Magnetic Nanoparticles as Effective Nanocarriers for Targeted Chemotherapy

Novel MamC‐mediated biomimetic magnetic nanoparticles (BMNPs) are proposed as valuable carriers for targeted chemotherapy because of the size (36 ± 12 nm) and of surface properties conferred by MamC coating. They are super‐paramagnetic at room and body temperatures, have a large magnetic moment per particle, mediate hyperthermia, are cytocompatible, and, having a negative surface charge at physiological pH, can be efficiently coupled with DOXOrubicin (DOXO) and a monoclonal antibody (mAb) directed against the human Met/hepatocyte growth factor receptor (overexpressed in many cancers) displaying coupling stability, while releasing DOXO at acidic pH. This release can be enhanced by hyperthermia. The DOXO‐mAb‐BMNPs selectively recognize Met, bind efficiently to Met⁺ tumor cells, and discharge DOXO within their nuclei more efficiently than DOXO‐BMNPs, exerting cytotoxicity. These data represent proof of concept for future in vivo experiments in which the controlled dual targeting (mAb‐mediated and magnetic) approach and combined (chemotherapy and hyperthermia) therapy will be studied.     

Biochemical and biomedical applications of multifunctional magnetic nanoparticles: a review

Nanotechnology offers tremendous potential for future medical diagnosis and therapy. Various types of nanoparticles have been extensively studied for numerous biochemical and biomedical applications. Magnetic nanoparticles are well-established nanomaterials that offer controlled size, ability to be manipulated by an external magnetic field, and enhancement of contrast in magnetic resonance imaging. As a result, these nanoparticles could have many applications including bacterial detection, protein purification, enzyme immobilization, contamination decorporation, drug delivery, hyperthermia, etc. All these biochemical and biomedical applications require that these nanoparticles should satisfy some prerequisites including high magnetization, good stability, biocompatibility, and biodegradability. Because of the potential benefits of multimodal functionality in biomedical applications, in this account highlights some general strategies to generate magnetic nanoparticle-based multifunctional nanostructures. After these magnetic nanoparticles are conjugated with proper ligands (e.g., nitrilotriacetate), polymers (e.g., polyacrylic acid, chitosan, temperature- and pH-sensitive polymers), antibodies, enzymes, and inorganic metals (e.g., gold), such biofunctional magnetic nanoparticles exhibit many advantages in biomedical applications. In addition, the multifunctional magnetic nanoparticles have been widely applied in biochemical fields including enzyme immobilization and protein purification.     

Magnetic Field‐Controlled Release of Paclitaxel Drug from Functionalized Magnetoelectric Nanoparticles

Using magnetoelectric nanoparticles (MENs) for targeted drug delivery and on‐demand, field‐controlled release can overcome the control challenges of the conventional delivery approaches. The magnetoelectric effect provides a new way to use an external magnetic field to remotely control the intrinsic electric fields that govern the binding forces between the functionalized surface of the MEN and the drug load. Here, a study is reported in which the composition of the intermediate functionalized layer is tailored to control not only the toxicity of the new nanoparticles but also the threshold magnetic field for the dissociation of the drug from 30‐nm CoFe₂O₄–BaTiO₃ core–shell MENs in a controllably wide field range, from below 10 to over 200 Oe, as required to facilitate superficial, intermediate, and deep‐tissue drug delivery. Paclitaxel is used as a test drug. Specific experiments are described to maintain low toxicity levels and to achieve controllable dissociation of the drug molecules from the MENs' surface at three different subranges—low (<10 Oe), moderate (100 Oe), and high (>200 Oe)—by selecting the following 2‐nm intermediate layers: i) glycerol monooleate (GMO), ii) Tween‐20, and iii) ethyl‐3‐(3‐dimethylaminopropyl)carbodiimide (EDC). Field‐dependent FTIR, absorption spectra, atomic force microscopy, magnetometry analysis, zeta‐potential measurements, and blood circulation experiments are used to study the described functionalization effects.     

Magnetic nanoparticle-based cancer therapy

Nanoparticles(NPs) with easily modified surfaces have been playing an important role in biomedicine.As cancer is one of the major causes of death,tremendous efforts have been devoted to advance the methods of cancer diagnosis and therapy.Recently,magnetic nanoparticles(MNPs) that are responsive to a magnetic field have shown great promise in cancer therapy.Compared with traditional cancer therapy,magnetic field triggered therapeutic approaches can treat cancer in an unconventional but more effective and safer way.In this review,we will discuss the recent progress in cancer therapies based on MNPs,mainly including magnetic hyperthermia,magnetic specific targeting,magnetically controlled drug delivery,magnetofection,and magnetic switches for controlling cell fate.Some recently developed strategies such as magnetic resonance imaging(MRI) monitoring cancer therapy and magnetic tissue engineering are also addressed.     

A Functionalized Hollow Mesoporous Silica Nanoparticles‐Based Controlled Dual‐Drug Delivery System for Improved Tumor Cell Cytotoxicity

Multifunctional nanoparticles for selectively targeting tumor cells and effectively delivering multiple drugs are urgently needed in cancer therapy. Here, a dual‐drug delivery system is prepared, based on functionalized hollow mesoporous silica nanoparticles (HMSNs). Doxorubicin (DOX) hydrochloride is loaded into the hollow core, and dichloro(1,2‐diaminocyclohexane)platinum (II) (DACHPt) is stored in the pores of the shell by the coordination interaction with the carboxyl groups modified on the pore walls, which also serves as barriers to control the DOX release. Detailed studies in vitro indicate that the DACHPt release is triggered by Cl^? through the cleavage of the coordination interaction, and the DOX release depends on the release rate of DACHPt and the environmental pH value. The surface of the mechanized nanoparticles is also modified by transferrin (Tf) to achieve the tumor specificity. Compared with individual drug delivery systems, the dual‐drug delivery system shows synergistic efficacy on the cell cytotoxicity (combination index = 0.30), resulting in improved tumor cell killing. The present dual‐drug delivery system provides a promising strategy to develop controlled and targeted combination therapies for efficient cancer treatment.     

Drug‐Conjugation Induced Self‐Assembly of Feather Keratin‐Based Prodrug for Tumor Intracellular Reduction Triggered Drug Delivery

As a kind of natural protein, keratin is widely investigated in the biomedical field. Here, for the first time, a keratin‐based prodrug (PK‐SS‐D) is designed for tumor intracellular reduction triggered drug delivery, by conjugating doxorubicin (DOX) onto poly(ethylene glycol) modified keratin (PEGylated keratin, PK) with a bioreducible disulfide linkage. The protein‐drug conjugate prodrug, with a drug content of 20%, can self‐assemble into micelles with a mean hydrodynamic diameter of 175 nm and a narrow distribution. The in vitro controlled release profiles reveal the reduction triggered thiolated DOX (DOX‐SH) release behavior of the PK‐SS‐D micelles, with a cumulative drug release up to 52% within 10 d in the simulated tumor microenvironment in a sustained releasing mode, and a low drug leakage of 17% in the simulated normal physiological medium. The enhanced tumor growth inhibition of the proposed PK‐SS‐D prodrug micelles is revealed by the methyl tetrazolium (MTT) assays, although the released DOX‐SH prodrug possesses a lower tumor growth inhibition than DOX.     

Self‐Assembly of Drug–Drug Conjugates as Drug Self‐Delivery System for Tumor‐Specific pH‐Triggered Release

An acid‐labile doxorubicin dimer (D‐DOX) is designed as drug–drug conjugate for tumor intracellular pH‐triggered release, by conjugating doxorubicin (DOX) with adipic acid dihydrazide (ADH). The dimer‐based surfactants modified with polyethylene glycol (PEG), DOX‐ADH‐DOX‐PEG or are synthesized by mono‐PEGylation and bi‐PEGylation, respectively. Then the prodrug nanoparticles are fabricated with different drug contents via dialyzing the mixture solution of D‐DOX and the PEGylated surfactants in dimethyl sulfoxide (DMSO) with different mass ratios against water. It is found that the smaller prodrug nanoparticles (142–163 nm) could be obtained with the mono‐PEGylated surfactant, than those of 157–225 nm with the bi‐PEGylated surfactant. Furthermore, the mono‐PEGylated surfactant results in a higher drug content of 51% due to their lower PEG contents. All prodrug nanoparticles could release DOX completely within 36 h at pH 5.0, with the premature drug leakage of less than 10% at pH 7.4. The 3‐(4,5‐dimethylthiazol‐2‐yl)‐2,5‐diphenyltetrazolium bromide (MTT) assays demonstrate the proposed drug self‐delivery system possessed an enhanced anticancer efficacy against HepG2 cells than the free DOX.     

In Vitro Studies of Fe3O4-ZIF-8 Core–Shell Nanoparticles Designed as Potential Theragnostics

Theragnostics represent a combination of therapy and diagnosis within one system. Herein, Fe₃O₄-ZIF-8 core–shell nanoparticles are developed and suggested as candidates for theragnostic applications in cancer treatment. A drug loaded metal–organic framework ZIF-8 (zeolitic imidazolate framework-8) represents the therapeutic tool, while the Fe₃O₄ core is included to enable the material visualization by magnetic resonance imaging (MRI). A reliable synthesis of Fe₃O₄-ZIF-8 core–shell nanoparticles of an average size below 100 nm is reported. The nanoparticles are characterized by FT-IR, TGA, XRPD, TEM, STEM-EDS, DLS, ICP-OES, CHN-elemental analysis, SQUID measurements, and MRI. Moreover, their chemical stability and in vitro cytotoxicity against fibroblast and selected cancer cell lines are evaluated. As a model drug, arsenic trioxide—a promising anticancer drug—is used. The drug release can be triggered by a pH change from 7.4 to 6.0 and the nanoparticles can be visualized by MRI in vitro, thus a potential theragnostic agent for cancer treatment is developed.     

Enhanced Physiological Stability and Long‐Term Toxicity/Biodegradation In Vitro/In Vivo of Monodispersed Glycerolphosphate‐Functionalized Bioactive Glass Nanoparticles

Monodispersed bioactive glass nanoparticles (BGNs) have received much attention in various biomedical applications such as tissue regeneration, drug/gene delivery, bioimaging, and cancer therapy. However, the poor dispersion stability of BGNs in a physiological environment has limited their wide biomedical applications. The long‐term in vitro/in vivo toxicity and biodegradation of BGNs are also not clear. Monodispersed glycerolphosphate‐functionalized BGNs (GP‐BGN) are synthesized and their stability under physiological environment in vitro, and long‐term biodegradation behavior in vitro and in vivo are investigated herein. GP‐BGN shows significantly enhanced particles stability in physiological environment, good hemocompatibility and cellular biocompatibility, as well as high cellular uptake ability. GP‐BGN also exhibits long‐term biodegradation behavior in vitro/in vivo and negligible biotoxicity (tissue and blood toxicity). This study demonstrates that monodispersed surface‐functionalized BGNs could be used as biocompatible and biodegradable nanomaterials for long‐term safe bioimaging and disease therapy.     

Human‐Serum‐Albumin‐Coated Prussian Blue Nanoparticles as pH‐/Thermotriggered Drug‐Delivery Vehicles for Cancer Thermochemotherapy

Constructing novel multimodal antitumor therapeutic nanoagents has attracted tremendous recent attention. In this work, a new drug‐delivery vehicle based on human‐serum‐albumin (HSA)‐coated Prussian blue nanoparticles (PB NPs) is synthesized. It is demonstrated that doxorubicin (DOX)/HSA is successfully loaded after in situ polymerization of dopamine onto PB NPs, and the PB@PDA/DOX/HSA NPs are highly compatible and stable in various physiological solutions. The NPs possess strong near‐infrared (NIR) absorbance, and excellent capability and stability of photothermal conversion for highly efficient photothermal therapy applications. Furthermore, a bimodal on‐demand drug release sensitively triggered by pH or NIR irradiation has been realized, resulting in a significant chemotherapeutic effect due to the preferential uptake and internalization of the NPs by cancer cells. Importantly, the thermochemotherapy efficacy of the NPs has been examined by a cell viability assay, revealing a remarkably superior synergistic anticancer effect over either monotherapy. Such multifunctional drug‐delivery systems composed of approved materials may have promising biomedical applications for antitumor therapy.     

Cobalt Phosphide Nanoparticles Applied as a Theranostic Agent for Multimodal Imaging and Anticancer Photothermal Therapy

Biocompatible single‐component theranostic nanoagents instinctly affording multiple imaging modalities with satisfying therapeutic functions are highly desirable for anticancer treatments. Although cobalt‐based phosphides are well‐recognized as competent electrocatalysts, their potentials for biomedical applications remain unexplored. In this work, cobalt phosphide nanoparticles (CoP NPs) are developed to be a powerful theranostic agent for multimodal imaging and anticancer photothermal therapy. The uniform CoP NPs in a size of ≈21 nm are synthesized via a facile thermal decomposition method, followed by surface modification. The resultant CoP NPs exhibit excellent compatibility and stability in water as well as various physiological solutions. Supported by the good biocompatibility, strong near‐infrared absorption, and high photothermal conversion property, significant photothermal effect of the NPs is demonstrated, realizing efficient hyperthermia ablation on cancer cells. Importantly, the CoP NPs have shown considerable capabilities on high‐contrast in vitro and in vivo triple‐modal imaging, including infrared thermal (IRT), photoacoustic (PA), and T₂‐weighted magnetic resonance (MR) imaging. This work has unraveled the promising potentials of CoP‐based nanoagent for precise diagnosis and efficient therapy.     

Near‐Infrared‐Light‐Induced Fast Drug Release Platform: Mesoporous Silica‐Coated Gold Nanoframes for Thermochemotherapy

Development of advanced theranostics for personalized medicine is of great interest. Herein, a multifunctional mesoporous silica‐based drug delivery carrier has been developed for efficient chemo/photothermal therapy. The unique Au nanoframes@mSiO₂ spheres are elaborately prepared by utilizing Ag@mSiO₂ yolk–shell spheres as the template through spatially confined galvanic replacement method. Compared with the Ag@mSiO₂ yolk–shell spheres, the resultant Au nanoframes@mSiO₂ spheres show a strong and broad near‐infrared (NIR) absorbance in the 550–1100 nm region, high surface areas, and good biocompatibility. When irradiated with a NIR laser with a power intensity of 1 W cm^?2 at 808 nm, they can become highly localized heat sources through the photothermal effect. Moreover, the photothermal effect of the Au nanoframes can significantly promote the fast release of doxorubicin. The in vitro studies show obvious synergistic effects combining photothermal therapy and chemotherapy in the Au nanoframes@mSiO₂ spheres against Hela cells. It is believed that the as‐obtained multifunctional vehicles provide a promising platform for the combination of hyperthermia and chemotherapy for cancer treatment application.     

Dextran‐Coated Antiferromagnetic MnO Nanoparticles for a T1‐MRI Contrast Agent with High Colloidal Stability

A simple approach to synthesize carboxymethyl dextran‐coated MnO nanoparticles (CMDex‐MnONPs) with high colloidal stability in physiological saline solutions is described here for potential applications as a magnetic resonance imaging (MRI) T₁ contrast agent. The thermal decomposition methodology is used to produce uniform MnONPs with an average size of around 20 nm, and its hydrophobic surface is modified with CMDex molecules, conferring hydrophilic properties. After CMDex coating, the nanoparticle presents high colloidal stability in concentrations ranging from 10 to 50 μg mL^?1, average hydrodynamic size (Z‐average) of 130 nm, polydispersity degree of ≈12%, and negative surface charge in both simulated body fluid solutions and pure water with zeta‐potential of –20 and –40 mV, respectively. The CMDex‐MnONPs with 20 nm show antiferromagnetic behavior at room temperature, and the magnetic properties are found to be strongly dependent of the nanoparticle size, increasing the contribution of the ferromagnetic Mn₃O₄ phase with decreasing size for nanoparticles about 3 nm. Cytotoxicity evaluation in cancerous and noncancerous cells in the range of 5.0–50.0 μg mL^?1 shows low toxicity for cancerous cells and lack of the same for healthy cells lines. Related to the magnetic properties, CMDex‐MnONP presents significant r₁ relaxivity and low r₂/r₁ relaxivity ratio. The results suggest that these nanoparticles display characteristics for potential applications as an MRI T₁ contrast agent.     

Carbon Dots‐Cluster‐DOX Nanocomposites Fabricated by a Co‐Self‐Assembly Strategy for Tumor‐Targeted Bioimaging and Therapy

Carbon‐based nanomaterials could afford versatile potential applications in biomedical optical imaging and as nanoparticle drug carriers, owing to their promising optical and biocompatible capabilities. In this paper, it is first found that amphipathic cetylpyridinium chloride (CPC)‐stabilized oil‐soluble carbon dots (CDs) could self‐assemble into hydrophilic CDs clusters with hydrophobic core under ultrasound, in which CPC acts as carbon source, stabilizer, and phase transfer agent. Next, the size‐control (for size‐dependent passive tumor targeting) and doxorubicin (DOX) uploading of aqueous CDs clusters, and subsequent surface charge modification via overcoating with cRGD‐ and octylamine‐modified polyacrylic acid (cRGD‐PAA‐OA) (reversing their surface charges into negative and introducing active tumor‐targeting ability) are explored systematically. Based on this sequential administration mode, CDs‐cluster‐DOX/cRGD‐PAA‐OA nanocomposites exhibit selective human malignant glioma cell line (U87MG) tumor targeting. In in vitro drug release experiments, the nanocomposites could release DOX timely. Owning to the dual tumor targeting effects and seasonable drug release, CDs‐cluster‐DOX/cRGD‐PAA‐OA show remarkably tumor targetability and enhanced antitumor efficacy (and reduced adverse reaction), comparing to free DOX in animal models. These results indicate that fabricating nanocomposite via co‐self‐assembly strategy is efficient toward drug delivery system for tumor‐targeting theranostic.     

Docetaxel‐Loaded Nanoparticles of Dendritic Amphiphilic Block Copolymer H40‐PLA‐b‐TPGS for Cancer Treatment

A dendritic amphiphilic block copolymer H40‐poly(d,l ‐lactide)‐block‐d‐α‐tocopheryl polyethylene glycol 1000 succinate (H40‐PLA‐b‐TPGS) is synthesized, which is then employed to develop a system of nanoparticles (NPs) loaded with docetaxel (DTX) as a model drug for cancer treatment due to its higher drug‐loading content and drug encapsulation efficiency, smaller particle size, faster drug release, and higher cellular uptake in comparison to the linear PLA polymer NPs and PLA‐b‐TPGS copolymer NPs. The drug‐loaded NPs are prepared by a modified nanoprecipitation method and characterized in terms of size and size distribution, surface morphology, drug release profile, and physical state of DTX. Cellular uptake of coumarin 6‐loaded NPs by MCF‐7 cancer cells is determined by flow cytometry and confocal laser scanning microscopy. The antitumor efficacy of the drug‐loaded NPs is investigated in vitro by MTT assay and in vivo by xenograft tumor model. The 72 h IC50 of the drug formulated in the PLA, PLA‐b‐TPGS, and H40‐PLA‐b‐TPGS NPs is found to be, 1.5 ± 0.3, 0.9 ± 0.1, and 0.15 ± 0.06 μg mL^?1, which are 7.3, 12.2, and 73.3‐fold effective than 11.0 ± 1.2 μg mL^?1 for Taxotere, respectively. Such advantages are further confirmed by the measurement of the tumor size and weight.