Carfilzomib-Loaded Ternary Polypeptide Nanoparticles Stabilized by Polycationic Complexation

Carfilzomib (CFZ) is a second-generation proteasome inhibitor showing great efficacy in multiple myeloma treatment, yet its clinical applications for other diseases such as solid cancers are limited due to low aqueous solubility and poor biostability. Ternary polypeptide nanoparticles (tPNPs) are drug carriers that we previously reported to overcome these pharmaceutical limitations by entrapping CFZ in the core of the nanoparticles and protecting the drugs from degradation in biological media. However, preclinical studies revealed that tPNPs would require further improvement in particle stability to suppress initial burst drug release and thus achieve prolonged inhibition of proteasome activity with CFZ against tumor cells in vivo. In this study, CFZ-loaded tPNPs are stabilized by polycations which have varying pKa values and thus differently modulate nanoparticle stability in response to solution pH. Through polyion complexation, the polycations appeared to stabilize the core of tPNPs entrapping CFZ-cyclodextrin inclusion complexes while allowing for uniform particle size before and after freeze drying. Interestingly, CFZ-loaded tPNPs (CFZ/tPNPs) showed pH-dependent drug release kinetics, which accelerated CFZ release as solution acidity increased (pH < 6) without compromising particle stability at the physiological condition (pH 7.4). In vitro cytotoxicity and proteasome activity assays confirmed that tPNPs stabilized with cationic polymers improved bioactivity of CFZ against CFZ-resistant cancer cells, which would be greatly beneficial in combination with pH-dependent drug release for treatment of solid cancers with drug resistance and tumor microenvironment acidosis by using CFZ and other proteasome inhibitors.

A pH-Responsive Asymmetric Microfluidic/Chitosan Device for Drug Release in Infective Bone Defect Treatment

Bacterial infection is currently considered to be one of the major reasons that leads to the failure of guided bone regeneration (GBR) therapy. Under the normal condition, the pH is neutral, while the microenvironment will become acid at the sites of infection. Here, we present an asymmetric microfluidic/chitosan device that can achieve pH-responsive drug release to treat bacterial infection and promote osteoblast proliferation at the same time. On-demand release of minocycline relies on a pH-sensitive hydrogel actuator, which swells significantly when exposed to the acid pH of an infected region. The PDMAEMA hydrogel had pronounced pH-sensitive properties, and a large volume transition occurred at pH 5 and 6. Over 12 h, the device enabled minocycline solution flowrates of 0.51-1.63 µg/h and 0.44-1.13 µg/h at pH 5 and 6, respectively. The asymmetric microfluidic/chitosan device exhibited excellent capabilities for inhibiting Staphylococcus aureus and Streptococcus mutans growth within 24 h. It had no negative effect on proliferation and morphology of L929 fibroblasts and MC3T3-E1 osteoblasts, which indicates good cytocompatibility. Therefore, such a pH-responsive drug release asymmetric microfluidic/chitosan device could be a promising therapeutic approach in the treatment of infective bone defects.

Enzymatic PCL-grafting to NH2-end grouped silica and development of microspheres for pH-stimulated release of a hydrophobic model drug

This study set out to evaluate novel PCL-based silica containing nanohybrids as the polymer matrix in a hydrophobic drug-loaded microsphere system. Nanohybrids were synthesized by PCL-grafting to NH₂-end grouped silica by in situ enzymatic ring opening polymerization of ε-caprolactone. Molecular weight and monomer conversion, PCL grafting percentage, thermal properties and crystallinity of the nanohybrids were determined by ¹H NMR, TGA, DSC and XRD. Synthesized nanohybrids had low crystallinity percentage (32 and 39 %) and molecular weight (4800 and 8700 g/mol), promising for controlled drug release applications. The nanohybrids were used for fabrication of trans-chalcone-loaded microspheres by O/W single emulsion solvent evaporation. Mean particle diameter of the microspheres were between 15 and 30 µm. The result of release studies showed that optimum microsphere formulations (AP4 and A2, respectively) had 61 and 64 % encapsulation efficiency. One of the more significant findings to emerge from this investigation is that TC release was extended to 16 and 37 days, in a controlled manner. TC release was significantly enhanced in acidic pH media (pH 3.6 and 5.6) indicating pH-dependent release from nanohybrid microspheres; releasing 80-100 % of the loaded drug in 4-14 days. Drug/polymer interactions and molecular structures were investigated by FT-IR spectroscopy and DSC analysis. According to the results obtained, enzymatically synthesized nanohybrids have potential for pH-dependent release of the model drug, trans-chalcone.

Engineered Magnetic Polymer Nanoparticles Can Ameliorate Breast Cancer Treatment Inducing Pyroptosis-Starvation along with Chemotherapy

Nanotechnology has shown a revolution in cancer treatments, including breast cancers. However, there remain some challenges and translational hurdles. Surgery, radiotherapy, and chemotherapy are the primary treatment methods for breast cancer, although drug combinations showed promising results in preclinical studies. Herein we report the development of a smart drug delivery system (DDS) to efficiently treat breast cancer by pyroptosis-starvation-chemotherapeutic combination. Cancer-starvation agent glucose oxidase was chemically attached to synthesized iron oxide nanoparticles which were entrapped inside poly(lactic-co-glycolic acid) along with apoptosis-associated speck-like protein containing a caspase recruitment domain plasmid and paclitaxel (PTX). An emulsion solvent evaporation method was used to prepare the DDS. The surface of the DDS was modified with chitosan to which aptamer was attached to achieve site-specific targeting. Hence, the prepared DDS could be targeted to a tumor site by both external magnet and aptamer to obtain an enhanced accumulation of drugs at the tumor site. The final size of the aptamer-decorated DDS was less than 200 nm, and the encapsulation efficiency of PTX was 76.5 ± 2.5%. Drug release from the developed DDS was much higher at pH 5.5 than at pH 7.4, ensuring the pH sensitivity of the DDS. Due to efficient dual targeting of the DDS, in vitro viability of 4T1 cells was reduced to 12.1 ± 1.6%, whereas the nontargeted group and free PTX group could reduce the viability of cells to 29.2 ± 2.4 and 46.2 ± 1.6%, respectively. Our DDS showed a synergistic effect in vitro and no severe side effects in vivo. This DDS has strong potential to treat various cancers.

Gold Nanoparticle Embedded Stimuli-Responsive Functional Glycopolymer: A Potential Material for Synergistic Chemo-Photodynamic Therapy of Cancer Cells

Photodynamic therapy has emerged as a non-invasive treatment modality for several types of cancers. However, conventional hydrophobic photosensitizers (PS) suffer from low water solubility and poor tumor-targeting ability. Therefore, PS modified with glycopolymers can offer adequate water solubility, biocompatibility and tumor-targeting ability due to the presence of multiple sugar units. In this study, a well-defined block copolymer (BCP) poly(3-O-methacryloyl-D-glucopyranose)-b-poly(2-(4-formylbenzoyloxy)ethylmethacrylate) (PMAG-b-PFBEMA) containing pendant glucose and aldehyde units was synthesized via reversible addition-fragmentation chain transfer (RAFT) polymerization method. A water-soluble PS (toluidine blue O; TBO) and a potent anti-cancer drug, Doxorubicin (Dox) were introduced to the polymer backbone via acid-labile Schiff-base reaction (PMAG-b-PFBEMA_TBO_Dox). The PMAG-b-PFBEMA_TBO_Dox was then anchored on the surface of AuNP via electrostatic interaction. This hybrid system exhibited excellent reactive oxygen species (ROS) generating ability under exposure of 630 nm LED along with triggered release of Dox under the acidic pH of tumor cells. The in vitro cytotoxicity study on human breast cancer cell line, MDA MB 231, for this hybrid system showed promising results due to the synergistic effect of ROS and Dox released. Thus, this glycopolymer-based dual (chemo-photodynamic) therapy model can work as potential material for future therapeutics. This article is protected by copyright. All rights reserved.

A Tri-Stimuli Responsive (Maghemite/PLGA)/Chitosan Nanostructure with Promising Applications in Lung Cancer

A (core/shell)/shell nanostructure (production performance ≈ 50%, mean diameter ≈ 330 nm) was built using maghemite, PLGA, and chitosan. An extensive characterization proved the complete inclusion of the maghemite nuclei into the PLGA matrix (by nanoprecipitation solvent evaporation) and the disposition of the chitosan shell onto the nanocomposite (by coacervation). Short-term stability and the adequate magnetism of the nanocomposites were demonstrated by size and electrokinetic determinations, and by defining the first magnetization curve and the responsiveness of the colloid to a permanent magnet, respectively. Safety of the nanoparticles was postulated when considering the results from blood compatibility studies, and toxicity assays against human colonic CCD-18 fibroblasts and colon carcinoma T-84 cells. Cisplatin incorporation to the PLGA matrix generated appropriate loading values (≈15%), and a dual pH- and heat (hyperthermia)-responsive drug release behaviour (≈4.7-fold faster release at pH 5.0 and 45 °C compared to pH 7.4 and 37 °C). The half maximal inhibitory concentration of the cisplatin-loaded nanoparticles against human lung adenocarcinoma A-549 cells was ≈1.6-fold less than that of the free chemotherapeutic. Such a biocompatible and tri-stimuli responsive (maghemite/PLGA)/chitosan nanostructure may found a promising use for the effective treatment of lung cancer.

Enzymatic/Magnetic Hybrid Micromotors for Synergistic Anticancer Therapy

Micro/nanomotors (MNMs), which propel by transforming various forms of energy into kinetic energy, have emerged as promising therapeutic nanosystems in biomedical applications. However, most MNMs used for anticancer treatment are only powered by one engine or provide a single therapeutic strategy. Although double-engined micromotors for synergistic anticancer therapy can achieve more flexible movement and efficient treatment efficacy, their design remains challenging. In this study, we used a facile preparation method to develop enzymatic/magnetic micromotors for synergetic cancer treatment via chemotherapy and starvation therapy (ST), and the size of micromotors can be easily regulated during the synthetic process. The enzymatic reaction of glucose oxidase, which served as the chemical engine, led to self-propulsion using glucose as a fuel and ST via a reduction in the energy available to cancer cells. Moreover, the incorporation of Fe₃O₄ nanoparticles as a magnetic engine enhanced the kinetic power and provided control over the direction of movement. Inherent pH-responsive drug release behavior was observed owing to the acidic decomposition of drug carriers in the intracellular microenvironment of cancer cells. This system displayed enhanced anticancer efficacy owing to the synergetic therapeutic strategies and increased cellular uptake in a targeted area because of the improved motion behavior provided by the double engines. Therefore, the demonstrated micromotors are promising candidates for anticancer biomedical microsystems.

β-Cyclodextrin-grafted hyaluronic acid as a supramolecular polysaccharide carrier for cell-targeted drug delivery

β-Cyclodextrin (β-CD) was grafted onto hyaluronic acid (HA) in a single step to generate a supramolecular biopolymer (HA-β-CD) that was explored for targeted drug delivery applications. Along with its excellent biocompatibility, the prepared HA-β-CD exhibits not only exceptionally high loading capacity for the model drugs doxorubicin and Rhodamine B through the formation of inclusion complexes with the β-CD component, but also the capability of targeted drug delivery to cancerous cells with a high level of expression of CD44 receptors, attributable to its HA component. The polymer can release the drug under slightly acidic conditions. With all its attributes, HA-β-CD may be a promising cancer-cell-targeting drug carrier.

Conjugated Polymer Nanoparticles Based on Copper Coordination for Real-Time Monitoring of pH-Responsive Drug Delivery

Metal coordination-driven composite systems have excellent stability and pH-responsive ability, making them suitable for specific drug delivery in physiological conditions. In this study, an anionic conjugated polymer PPEIDA with a poly(p-phenylene ethynylene) backbone and iminodiacetic acid (IDA) side chains is used as a drug carrier to construct a class of pH-responsive nanoparticles, PPEIDA-Cu-DOX conjugated polymer nanoparticles (CPNs), by taking advantage of the metal coordination interaction of Cu²⁺ with PPEIDA and the drug doxorubicin (DOX). PPEIDA-Cu-DOX CPNs have high drug loading and encapsulation efficiency (EE), calculated to be 54.30 ± 1.10 and 95.80 ± 0.84%, respectively. Due to the good spectral overlap, Förster resonance energy transfer (FRET) takes place between PPEIDA and the drug DOX, which enables the observation of the loading and the release of DOX from CPNs in an acidic environment by monitoring fluorescence emission changes. Therefore, PPEIDA-Cu-DOX CPNs can also be used in real-time cell imaging to monitor drug release in addition to delivering DOX targeting tumor cells. Compared with free DOX, PPEIDA-Cu-DOX CPNs show a similar inhibition to tumor cells and lower toxicity to normal cells. Our results demonstrate the feasibility and potential of constructing pH-responsive CPNs via metal-ligand coordination interactions for cancer treatment.

Carbon Nano-Onions Reinforced Multilayered Thin Film System for Stimuli-Responsive Drug Release

Herein, poly (N-(4-aminophenyl) methacrylamide))-carbon nano-onions (PAPMA-CNOs = f-CNOs) and anilinated-poly (ether ether ketone) (AN-PEEK) have synthesized, and AN-PEEK/f-CNOs composite thin films were primed via layer-by-layer (LbL) self-assembly for stimuli-responsive drug release. The obtained thin films exhibited pH-responsive drug release in a controlled manner; pH 4.5 = 99.2% and pH 6.5 = 59.3% of doxorubicin (DOX) release was observed over 15 days. Supramolecular π-π stacking interactions between f-CNOs and DOX played a critical role in controlling drug release from thin films. Cell viability was studied with human osteoblast cells and augmented viability was perceived. Moreover, the thin films presented 891.4 ± 8.2 MPa of the tensile strength (σult), 43.2 ± 1.1 GPa of Young's modulus (E), and 164.5 ± 1.7 Jg-1 of toughness (K). Quantitative scrutiny revealed that the well-ordered aligned nanofibers provide critical interphase, and this could be responsible for augmented tensile properties. Nonetheless, a pH-responsive and mechanically robust biocompatible thin-film system may show potential applications in the biomedical field.

Gemcitabine-Loaded Magnetically Responsive Poly(ε-caprolactone) Nanoparticles against Breast Cancer

A reproducible and efficient interfacial polymer disposition method has been used to formulate magnetite/poly(ε-caprolactone) (core/shell) nanoparticles (average size ≈ 125 nm, production performance ≈ 90%). To demonstrate that the iron oxide nuclei were satisfactorily embedded within the polymeric solid matrix, a complete analysis of these nanocomposites by, e.g., electron microscopy visualizations, energy dispersive X-ray spectroscopy, Fourier-transform infrared spectroscopy, electrophoresis, and contact angle goniometry was conducted. The magnetic responsive behaviour of these nanoparticles was quantitatively characterized by the hysteresis cycle and qualitatively investigated by visualization of the colloid under exposure to a 0.4 T magnet. Gemcitabine entrapment into the polymeric shell reported adequate drug loading values (≈11%), and a biphasic and pH-responsive drug release profile (≈ four-fold faster Gemcitabine release at pH 5.0 compared to pH 7.4). Cytotoxicity studies in MCF-7 human breast cancer cells proved that the half maximal inhibitory concentration of Gem-loaded nanocomposites was ≈ two-fold less than that of the free drug. Therefore, these core/shell nanoparticles could have great possibilities as a magnetically targeted Gemcitabine delivery system for breast cancer treatment.

Development of Functionalized Carbon Nano-Onions Reinforced Zein Protein Hydrogel Interfaces for Controlled Drug Release

In the current study, poly 4-mercaptophenyl methacrylate-carbon nano-onions (PMPMA-CNOs = f-CNOs) reinforced natural protein (zein) composites (zein/f-CNOs) are fabricated using the acoustic cavitation technique. The influence of f-CNOs inclusion on the microstructural properties, morphology, mechanical, cytocompatibility, in-vitro degradation, and swelling behavior of the hydrogels are studied. The tensile results showed that zein/f-CNOs hydrogels fabricated by the acoustic cavitation system exhibited good tensile strength (90.18 MPa), compared with the hydrogels fabricated by the traditional method and only microwave radiation method. It reveals the magnitude of physisorption and degree of colloidal stability of f-CNOs within the zein matrix under acoustic cavitation conditions. The swelling behaviors of hydrogels were also tested and improved results were noticed. The cytotoxicity of hydrogels was tested with osteoblast cells. The results showed good cell viability and cell growth. To explore the efficacy of hydrogels as drug transporters, 5-fluorouracil (5-FU) release was measured under gastric and intestinal pH environment. The results showed pH-responsive sustained drug release over 15 days of study, and pH 7.4 showed a more rapid drug release than pH 2.0 and 4.5. Nonetheless, all the results suggest that zein/f-CNOs hydrogel could be a potential pH-responsive drug transporter for a colon-selective delivery system.

Synthesis of silica-alginate nanoparticles and their potential application as pH-responsive drug carriers

Composite silica-alginate nanoparticles were prepared via silica sol-gel technique using a water-in-oil microemulsion system. In our system, cyclohexane served as the bulk oil phase into which aqueous solutions of sodium alginate were dispersed as droplets that confined nanoparticle formation after addition of tetraethylorthosilicate (TEOS). Our studies showed that much of the particle growth is completed within the first 24 hours and reaction times up to 120 hours only resulted in an additional 5% increase in particle diameter. Average particle size was found to decrease with increasing water-to-surfactant molar ratio (R) and with increasing cocentration of alginate in the aqueous phase. The potential for drug loading during particle formation was demonstrated using rhodamine B as a model drug. In vitro release studies showed that particles incubated in pH 2.5 phosphate buffer released only about 7% of the drug load in 27 days, while 42% was released in pH 7.5 phosphate buffer over the same period. Analysis of the release profile suggested that rhodamine B was homogeneously distributed throughout the particle and that the drug diffusivity was 40-fold greater in pH 7.5 buffer compared to that at pH 2.5. These results suggest that silica-alginate nanoparticles could be used as a pH-responsive drug carrier for controlled drug release.

Structural insights into pH-responsive drug release of self-assembling human serum albumin-silk fibroin nanocapsules

Inflammation processes are associated with significant decreases in tissue or lysosomal pH from 7.4 to 4, a fact that argues for the application of pH-responsive drug delivery systems. However, for their design and optimization a full understanding of the release mechanism is crucial. In this study we investigated the pH-depending drug release mechanism and the influence of silk fibroin (SF) concentration and SF degradation degree of human serum albumin (HSA)-SF nanocapsules. Sonochemically produced nanocapsules were investigated regarding particle size, colloidal stability, protein encapsulation, thermal stability and drug loading properties. Particles of the monodisperse phase showed average hydrodynamic radii between 438 and 888 nm as measured by DLS and AFM and a zeta potential of -11.12 ± 3.27 mV. Together with DSC results this indicated the successful production of stable nanocapsules. ATR-FTIR analysis demonstrated that SF had a positive effect on particle formation and stability due to induced beta-sheet formation and enhanced crosslinking. The pH-responsive release was found to depend on the SF concentration. In in-vitro release studies, HSA-SF nanocapsules composed of 50% SF showed an increased pH-responsive release for all tested model substances (Rhodamine B, Crystal Violet and Evans Blue) and methotrexate at the lowered pH of 4.5 to pH 5.4, while HSA capsules without SF did not show any pH-responsive drug release. Mechanistic studies using confocal laser scanning microscopy (CLSM) and small angle X-ray scattering (SAXS) analyses showed that increases in particle porosity and decreases in particle densities are directly linked to pH-responsive release properties. Therefore, the pH-responsive release mechanism was identified as diffusion controlled in a novel and unique approach by linking scattering results with in-vitro studies. Finally, cytotoxicity studies using the human monocytic THP-1 cell line indicated non-toxic behavior of the drug loaded nanocapsules when applied in a concentration of 62.5 µg mL^-1. Based on the obtained release properties of HSA-SF nanocapsules formulations and the results of in-vitro MTT assays, formulations containing 50% SF showed the highest requirements arguing for future in vivo experiments and application in the treatment of inflammatory diseases.

Lectin-conjugated pH-responsive mesoporous silica nanoparticles for targeted bone cancer treatment

A novel multifunctional nanodevice based in doxorubicin (DOX)-loaded mesoporous silica nanoparticles (MSNs) as nanoplatforms for the assembly of different building blocks has been developed for bone cancer treatment. These building blocks consists of: i) a polyacrylic acid (PAA) capping layer grafted to MSNs via an acid-cleavable acetal linker, to minimize premature cargo release and provide the nanosystem of pH-responsive drug delivery ability; and ii) a targeting ligand, the plant lectin concanavalin A (ConA), able to selectively recognize, bind and internalize owing to certain cell-surface glycans, such as sialic acids (SA), overexpressed in given tumor cells. This multifunctional nanosystem exhibits a noticeable higher internalization degree into human osteosarcoma cells (HOS), overexpressing SA, compared to healthy preosteoblast cells (MC3T3-E1). Moreover, the results indicate that small DOX loading (2.5 µg mL^-1) leads to almost 100% of osteosarcoma cell death in comparison with healthy bone cells, which significantly preserve their viability. Besides, this nanodevice has a cytotoxicity on tumor cells 8-fold higher than that caused by the free drug. These findings demonstrate that the synergistic combination of different building blocks into a unique nanoplatform increases antitumor effectiveness and decreases toxicity towards normal cells. This line of attack opens up new insights in targeted bone cancer therapy.

STATEMENT OF SIGNIFICANCE

The development of highly selective and efficient tumor-targeted smart drug delivery nanodevices remains a great challenge in nanomedicine. This work reports the design and optimization of a multifunctional nanosystem based on mesoporous silica nanoparticles (MSNs) featuring selectivity towards human osteosarcoma cells and pH-responsive antitumor drug delivery capability. The novelty and originality of this manuscript relies on proving that the synergistic assembly of different building blocks into a unique nanoplatform increases antitumor effectiveness and decreases toxicity towards healthy cells, which constitutes a new paradigm in targeted bone cancer therapy.

Dual-Stimuli Responsive Nanotheranostics for Multimodal Imaging Guided Trimodal Synergistic Therapy

Multimodal imaging guided synergistic therapy promises more accurate diagnosis than any single imaging modality, and higher therapeutic efficiency than any single one or their simple "mechanical" combination. Herein, we report a dual-stimuli responsive nanotheranostic based on a hierarchical nanoplatform, composed of mesoporous silica-coated gold nanorods (GNR@SiO2), Indocyanine Green (ICG), and 5-fluorouracil (5-FU), for in vivo multimodal imaging guided synergistic therapy. The 5-FU loaded ICG-conjugated silica-coated gold nanorods (GNR@SiO2-5-FU-ICG) was able to response specifically to the two stimuli of pH change and near-infrared (NIR) light irradiation. Both the NIR light irradiation and acidic environment accelerated the 5-FU release. Meanwhile, the heat generation and singlet oxygen production can be induced by GNR@SiO2-5-FU-ICG upon light irradiation. Most intriguingly, the nanoplatform also promises multimodal imaging such as two-photon luminescence, fluorescence, photoacoustic, photothermal imaging, as well as trimodal synergistic therapy such as photothermal therapy (PTT), photodynamic therapy (PDT), and chemotherapy. The cancer theranostic capability of GNR@SiO2-5-FU-ICG was evaluated both in vitro and in vivo. The trimodal synergistic therapy with the guidance of multimodal imaging exhibited remarkably enhanced treatment efficacy. This concept of a hierarchical nanoplatform integrates multiple diagnostic/therapeutic modalities into one platform, which can potentially be applied as personalized nanomedicine with drug delivery, diagnosis, and treatment.

Self-assembled vehicle construction via boronic acid coupling and host-guest interaction for serum-tolerant DNA transport and pH-responsive drug delivery

By exploiting boronic acid coupling and host-guest chemistry, a pH-responsive drug/gene co-delivery nanoplatform is designed for cancer treatments with the excellently serum-tolerant transfection activity and the capability to load and release hydrophobic drugs in an acidity-accelerated manner. Via boronate linkage, γ-CD is allowed to spontaneously attach onto phenylboronic-acid-modified oligoethylenimine (PEI1.8K-PB2.9 ) at neutral condition. The formed vehicle/DNA nanoformulation is thus surrounded densely by γ-CD moieties to biomimic the carbohydrate-rich cell surface, providing a novel approach to overcome serum-susceptible drawbacks frequently associated with synthetic gene carriers. PEI1.8K-PB2.9 -γ-CD conjugates demonstrate significantly improved cell-biocompatibility and transfection activity over PEI1.8K-PB2.9 . Noticeably, serum-associated inhibition effect is negligible for PEI1.8K-PB2.9 -γ-CD-mediated transfection whereas marked transfection reduction occurs for PEI25K and PEI1.8K-PB2.9 upon serum exposure. Consequently, PEI1.8K-PB2.9 -γ-CDs afford much higher transfection efficiency, that is, 25-fold higher luciferase expression over PEI25K in presence of 30% serum. An anticancer drug of doxorubicin (DOX) is shown to be readily accommodated into the nanoformulation via host-guest chemistry and intracellularly co-delivered together with plasmid DNA. Due to the acidity-labile feature of boronate linkage, DOX/γ-CD inclusion complexes would be mostly detached from the nanoformulation triggered by acidity, leading to faster drug release. Furthermore, drug inclusion does not alter the serum-compatible transfection efficiency of PEI1.8K-PB2.9 -γ-CD.

pH-Responsive Theranostic Polymer-Caged Nanobins (PCNs): Enhanced Cytotoxicity and T1 MRI Contrast by Her2-Targeting

A PCN theranostic platform comprises a doxorubicin (DXR)-loaded liposomal core and an acid-sensitive polymer shell that is functionalized with Herceptin and Gd^III-based MRI contrast agents. In vitro testing reveals a 14-fold increase in DXR-based cytotoxicity versus a non-targeted analogue and an 120-fold improvement in cellular Gd^III-uptake in comparison with clinically approved DOTA-Gd^III, leading to significant T₁ MRI contrast enhancement.