Bioimaging for targeted delivery of hyaluronic Acid derivatives to the livers in cirrhotic mice using quantum dots

Dual-targeting galactose-functionalized hyaluronic acid modified lipid nanoparticles delivering silybin for alleviating alcoholic liver injury

Alcoholic liver injury stands as a predominant pathogenic contributor to the global burden of liver diseases, with alcohol consumption serving as a significant determinant of worldwide morbidity and mortality. Given that liver-targeted therapy for mitigating alcoholic liver injury remains to be a major clinical challenge due to the poor specificity and instability associated with single targeting modification in actively targeted nanomedicine systems, bifunctional targeting modification may serve as a more promising strategy. Here, galactose-functionalized hyaluronic acid (Gal-HA) coated cationic solid lipid nanoparticles carrying silybin (Gal-HA/SIL-SLNPs) featuring dual-targeting hyaluronic acid (HA) and galactose (Gal) moieties, enabled specific liver surface targeting of asialoglycoprotein receptor (ASGPR) and cluster of differentiation 44 (CD44) proteins to enhance silybin uptake, while simultaneously ameliorating the deficiencies of positively charged lipid nanoparticles as drug carriers and preserving their stability in the bloodstream. Based on the findings, Gal-HA/SIL-SLNPs with excellent biocompatibility demonstrated improved cellular internalization and liver distribution, while also displaying ideal curative properties in a mouse model of alcohol-induced liver injury without causing damage to other organs. This work suggests that Gal-HA/SIL-SLNPs with dual modification may represent an encouraging approach for developing more effective liver targeted nano-drug delivery systems to achieve accurate medication for alcoholic liver injury.

A branched polymer-based agent for efficient and precise targeting of fibrosis diseases by magnetic resonance imaging

Herein, we synthesized and characterized gadolinium-based hyperbranched polymers, POADGd and PODGd, through RAFT polymerization as magnetic resonance imaging (MRI) contrast agents for detecting fibrosis. POADGd and PODGd contain biocompatible short-chain OEGMA to prolong blood circulation, and they can be decomposed in response to ROS after MRI examination to prevent potential accumulation. The relaxivities of POADGd and PODGd are 9.81 mM-1 s-1 and 9.58 mM-1 s-1 respectively, which are significantly higher than that of DTPA-Gd, a clinically used agent (3.74 mM-1 s-1). In comparison with PODGd, POADGd can specifically target allysine in fibrosis tissues through its oxyamine groups. Therefore, it displays a sharp spatial resolution and a high signal-to-noise ratio in the liver and lung fibrosis tissue at a field strength of 3.0 T or 7.0 T, and the morphology of these fibrosis tissues is accurately delineated. Our MRI diagnosis results based on POADGd are highly aligned with those from pathological examinations, while MRI diagnosis could avoid invasive biopsy. In addition, POADGd shows excellent biosafety and low toxicity. Therefore, POADGd could be applied to non-invasively and accurately diagnose liver and lung fibrosis diseases.

RNA nanomedicine in liver diseases

The remarkable impact of RNA nanomedicine during the COVID-19 pandemic has demonstrated the expansive therapeutic potential of this field in diverse disease contexts. In recent years, RNA nanomedicine targeting the liver has been paradigm-shifting in the management of metabolic diseases such as hyperoxaluria and amyloidosis. RNA nanomedicine has significant potential in the management of liver diseases, where optimal management would benefit from targeted delivery, doses titrated to liver metabolism, and personalized therapy based on the specific site of interest. In this review, we discuss in-depth the different types of RNA and nanocarriers used for liver targeting along with their specific applications in metabolic dysfunction-associated steatotic liver disease, liver fibrosis, and liver cancers. We further highlight the strategies for cell-specific delivery and future perspectives in this field of research with the emergence of small activating RNA, circular RNA, and RNA base editing approaches.

Advances in active targeting of ligand-directed polymeric nanomicelles via exploiting overexpressed cellular receptors for precise nanomedicine

Many of the utilized drugs which already exist in the pharmaceutical sector are hydrophobic in nature. These drugs are characterized by being poorly absorbed and difficult to formulate in aqueous environments with low bioavailability, which could result in consuming high and frequent doses in order to fulfil the required therapeutic effect. As a result, there is a decisive demand to find modern alternatives to overcome all these drawbacks. Self-assembling polymeric nanomicelles (PMs) with their unique structure appear to be a fascinating choice as a pharmaceutical carrier system for improving the solubility & bioavailability of many drugs. PMs as drug carriers have many advantages including suitable size, high stability, prolonged circulation time, elevated cargo capacity and controlled therapeutic release. Otherwise, the pathological features of some diseased cells, like cancer, allow PMs with particle size <200 nm to be passively uptaken via enhanced permeability and retention phenomenon (EPR). However, the passive targeting approach was proven to be insufficient in many cases. Consequently, the therapeutic efficiency of these PMs can be further reinforced by enhancing their cellular internalization via incorporating targeting ligands. These targeting ligands can enhance the assemblage of loaded cargos in the intended tissues via receptor-mediated endocytosis through exploiting receptors robustly expressed on the exterior of the intended tissue while minimizing their toxic effects. In this review, the up-to-date approaches of harnessing active targeting ligands to exploit certain overexpressed receptors will be summarized concerning the functionalization of the exterior of PMs for ameliorating their targeting potential in the scope of nanomedicine.

Advances in Noninvasive Molecular Imaging Probes for Liver Fibrosis Diagnosis

Liver fibrosis is a wound-healing response to chronic liver injury, which may lead to cirrhosis and cancer. Early-stage fibrosis is reversible, and it is difficult to precisely diagnose with conventional imaging modalities such as magnetic resonance imaging, positron emission tomography, single-photon emission computed tomography, and ultrasound imaging. In contrast, probe-assisted molecular imaging offers a promising noninvasive approach to visualize early fibrosis changes in vivo, thus facilitating early diagnosis and staging liver fibrosis, and even monitoring of the treatment response. Here, the most recent progress in molecular imaging technologies for liver fibrosis is updated. We start by illustrating pathogenesis for liver fibrosis, which includes capillarization of liver sinusoidal endothelial cells, cellular and molecular processes involved in inflammation and fibrogenesis, as well as processes of collagen synthesis, oxidation, and cross-linking. Furthermore, the biological targets used in molecular imaging of liver fibrosis are summarized, which are composed of receptors on hepatic stellate cells, macrophages, and even liver collagen. Notably, the focus is on insights into the advances in imaging modalities developed for liver fibrosis diagnosis and the update in the corresponding contrast agents. In addition, challenges and opportunities for future research and clinical translation of the molecular imaging modalities and the contrast agents are pointed out. We hope that this review would serve as a guide for scientists and students who are interested in liver fibrosis imaging and treatment, and as well expedite the translation of molecular imaging technologies from bench to bedside.

Liver Cell Type-Specific Targeting by Nanoformulations for Therapeutic Applications

Hepatocytes exert pivotal roles in metabolism, protein synthesis and detoxification. Non-parenchymal liver cells (NPCs), largely comprising macrophages, dendritic cells, hepatic stellate cells and liver sinusoidal cells (LSECs), serve to induce immunological tolerance. Therefore, the liver is an important target for therapeutic approaches, in case of both (inflammatory) metabolic diseases and immunological disorders. This review aims to summarize current preclinical nanodrug-based approaches for the treatment of liver disorders. So far, nano-vaccines that aim to induce hepatitis virus-specific immune responses and nanoformulated adjuvants to overcome the default tolerogenic state of liver NPCs for the treatment of chronic hepatitis have been tested. Moreover, liver cancer may be treated using nanodrugs which specifically target and kill tumor cells. Alternatively, nanodrugs may target and reprogram or deplete immunosuppressive cells of the tumor microenvironment, such as tumor-associated macrophages. Here, combination therapies have been demonstrated to yield synergistic effects. In the case of autoimmune hepatitis and other inflammatory liver diseases, anti-inflammatory agents can be encapsulated into nanoparticles to dampen inflammatory processes specifically in the liver. Finally, the tolerance-promoting activity especially of LSECs has been exploited to induce antigen-specific tolerance for the treatment of allergic and autoimmune diseases.

Hyaluronic Acid-Based Nanocarriers for Anticancer Drug Delivery

Hyaluronic acid (HA), a main component of the extracellular matrix, is widely utilized to deliver anticancer drugs due to its biocompatibility, biodegradability, non-toxicity, non-immunogenicity and numerous modification sites, such as carboxyl and hydroxyl groups. Moreover, HA serves as a natural ligand for tumor-targeted drug delivery systems, as it contains the endocytic HA receptor, CD44, which is overexpressed in many cancer cells. Therefore, HA-based nanocarriers have been developed to improve drug delivery efficiency and distinguish between healthy and cancerous tissues, resulting in reduced residual toxicity and off-target accumulation. This article comprehensively reviews the fabrication of anticancer drug nanocarriers based on HA in the context of prodrugs, organic carrier materials (micelles, liposomes, nanoparticles, microbubbles and hydrogels) and inorganic composite nanocarriers (gold nanoparticles, quantum dots, carbon nanotubes and silicon dioxide). Additionally, the progress achieved in the design and optimization of these nanocarriers and their effects on cancer therapy are discussed. Finally, the review provides a summary of the perspectives, the lessons learned so far and the outlook towards further developments in this field.

Smart Nanomaterials in Cancer Theranostics: Challenges and Opportunities

Cancer is ranked as the second leading cause of death globally. Traditional cancer therapies including chemotherapy are flawed, with off-target and on-target toxicities on the normal cells, requiring newer strategies to improve cell selective targeting. The application of nanomaterial has been extensively studied and explored as chemical biology tools in cancer theranostics. It shows greater applications toward stability, biocompatibility, and increased cell permeability, resulting in precise targeting, and mitigating the shortcomings of traditional cancer therapies. The nanoplatform offers an exciting opportunity to gain targeting strategies and multifunctionality. The advent of nanotechnology, in particular the development of smart nanomaterials, has transformed cancer diagnosis and treatment. The large surface area of nanoparticles is enough to encapsulate many molecules and the ability to functionalize with various biosubstrates such as DNA, RNA, aptamers, and antibodies, which helps in theranostic action. Comparatively, biologically derived nanomaterials perceive advantages over the nanomaterials produced by conventional methods in terms of economy, ease of production, and reduced toxicity. The present review summarizes various techniques in cancer theranostics and emphasizes the applications of smart nanomaterials (such as organic nanoparticles (NPs), inorganic NPs, and carbon-based NPs). We also critically discussed the advantages and challenges impeding their translation in cancer treatment and diagnostic applications. This review concludes that the use of smart nanomaterials could significantly improve cancer theranostics and will facilitate new dimensions for tumor detection and therapy.

Melanin theranostic nanoplatform as an efficient drug delivery system for imaging-guided renal fibrosis therapy

As renal fibrosis nanotherapeutics, the endogenous biomaterial melanin not only has natural biocompatibility and biodegradability but also has inherent photoacoustic imaging ability and certain anti-inflammatory effects. These properties determine that melanin can not only as a carrier of medication but also track the biodistribution and renal uptake of drugs in vivo by photoacoustic imaging in real-time. Curcumin is a natural compound with biological activity, which has excellent ROS scavenging ability and good anti-inflammatory property. These materials appear more advantages in the development of nanoscale diagnostic and therapeutic platforms for future clinical translation. Herein, this study developed curcumin-loaded melanin nanoparticles (MNP-PEG-CUR NPs) as an efficient medication delivery system for photoacoustic imaging guidance renal fibrosis treatment. The nanoparticles are about 10 nm in size, exhibit good renal clearance efficiency, excellent photoacoustic imaging ability, and good in vitro and in vivo biocompatibility. These preliminary results indicated that MNP-PEG-CUR have clinically applicable potential as a therapeutic nanoplatform for renal fibrosis.

Folate Decoration Supports the Targeting of Camptothecin Micelles against Activated Hepatic Stellate Cells and the Suppression of Fibrogenesis

As the central cellular player in fibrogenesis, activated hepatic stellate cells (aHSCs) are the major target of antifibrotic nanomedicines. Based on our finding that activated HSCs increase the expression of folate receptor alpha (FRα), we tried to apply folic acid (FA) decoration to generate an active drug-targeting at aHSCs and suppress hepato-fibrogenesis. FA-conjugated poly(ethylene glycol)-poly(ε-caprolactone) copolymers (PEG-PCL) were synthesized and self-assembled into the spherical micelles that owned a uniform size distribution averaging at 60 nm, excellent hemo- and cyto-compatibility, and pH-sensitive stability. These FA-modified micelles were preferentially ingested by aHSCs as expected and accumulated more in acutely CCl₄ injured mouse livers compared to nondecorated counterparts. Such an aHSC targetability facilitated the loaded medicinal camptothecin (CPT) to achieve a greater therapeutic efficacy and inhibition of MF phenotypic genes in aHSCs. Encouragingly, though free CPT and nontargeting CPT micelles produced negligible curative outcomes, FA-decorated CPT micelles yielded effectively remedial effects in chronically CCl₄-induced fibrotic mice, as represented by a significant shrinkage of aHSC population, suppression of fibrogenesis, and recovery of liver structure and function, clearly indicating the success of the folate decoration-supported aHSC-targeted strategy for antifibrotic nanomedicines in fibrosis resolution.

Sequential Nano-Penetrators of Capillarized Liver Sinusoids and Extracellular Matrix Barriers for Liver Fibrosis Therapy

During liver fibrogenesis, liver sinusoidal capillarization and extracellular matrix (ECM) deposition construct dual pathological barriers to drug delivery. Upon capillarization, the vanished fenestrae in liver sinusoidal endothelial cells (LSECs) significantly hinder substance exchange between blood and liver cells, while excessive ECM further hinders the delivery of nanocarriers to activated hepatic stellate cells (HSCs). Herein, an efficient nanodrug delivery system was constructed to sequentially break through the capillarized LSEC barrier and the deposited ECM barrier. For the first barrier, LSEC-targeting and fenestrae-repairing nanoparticles (named HA-NPs/SMV) were designed on the basis of the modification with hyaluronic acid and the loading of simvastatin (SMV). For the second barrier, collagenase I and vitamin A codecorated nanoparticles with collagen-ablating and HSC-targeting functions (named CV-NPs/siCol1α1) were prepared to deliver siCol1α1 with the goal of inhibiting collagen generation and HSC activation. Our in vivo results showed that upon encountering the capillarized LSEC barrier, HA-NPs/SMV rapidly released SMV and exerted a fenestrae-repairing function, which allowed more CV-NPs/siCol1α1 to enter the space of Disse to degrade deposited collagen and finally to achieve higher accumulation in activated HSCs. Scanning electronic microscopy images showed the recovery of liver sinusoids, and analysis of liver tissue sections demonstrated that HA-NPs/SMV and CV-NPs/siCol1α1 had a synergetic effect. Our pathological barrier-normalization strategy provides an antifibrotic therapeutic regimen.

Glyco-nanotechnology: A biomedical perspective

Glycans govern cellular signaling through glycan-protein and glycan-glycan crosstalk. Disruption in the crosstalk initiates 'rogue' signaling and pathology. Nanomaterials supply platforms for multivalent displays of glycans, mediate 'rogue' signal correction, and provide disease treatment modalities (therapeutics). The decorated glycans also target overexpressed lectins on unhealthy cells and direct metal nanoparticles such as gold, iron oxide, and quantum dots to the site of infection. The nanoparticles inform us about the state of the disease (diagnosis) through their distinct optical, magnetic, and electronic properties. Glyco-nanoparticles can sense disease biomarkers, report changes in protein-glycan interactions, and safeguard quality control (analysis). Here we review the current state of glyco-nanotechnology focusing on diagnosis, therapeutics, and analysis of human diseases. We highlight how glyco-nanotechnology could aid in improving diagnostic methods for the detection of disease biomarkers with magnetic resonance imaging (MRI) and fluorescence imaging (FLI), enhance therapeutics such as anti-adhesive treatment of cancer and vaccines against pneumonia, and advance analysis such as the rapid detection of pharmaceutical heparin contaminant and recombinant SARS-COV-2 spike protein. We illustrate these progressions and outline future potentials of glyco-nanotechnology in advancing human health.

Preparation of Nanosensors for Detecting the Activity of Glycosaminoglycan Cleaving Enzymes

Glycosaminoglycans (GAGs) play crucial roles in several biological processes including cell division, angiogenesis, anticoagulation, neurogenesis, axon guidance and growth, and viral and bacterial infections among others. The GAG cleaving hydrolases/lyases play a major role in the control of GAG structures, functions, and turn over. Dysregulation of GAG cleaving enzymes in vivo are linked to a number of human diseases including cancer, diabetes, atherosclerosis, arthritis, inflammation, and cardiovascular diseases. Several GAG cleaving enzymes are widely used for studying GAG glycobiology: heparitinases, chondroitinases, heparanases, hyaluronidases, and keratanases. Herein, we describe a method to synthesize four distinct nanometal surface energy transfer (NSET)-based gold-GAG-dye conjugates (nanosensors). Heparin, chondroitin sulfate, heparan sulfate, and hyaluronic acid are covalently linked with distinct fluorescent dyes and then immobilized on gold nanoparticles (AuNPs) to build nanosensors that serve as excellent substrates for GAG cleaving enzymes. Upon treatment of nanosensors with their respective GAG cleaving enzymes, dye-labeled oligosaccharides/disaccharides are released from AuNPs resulting in enhanced fluorescence recovery. These nanosensors have a great promise as diagnostic tools in various human pathophysiological conditions for detecting dysregulated expression of GAG cleaving enzymes and also as a sensitive analytical tool for assessing the quality control of pharmaceutical grade heparin polysaccharides that are produced in millions of small- and medium-sized animal slaughter houses worldwide.

Harnessing X-Ray Energy-Dependent Attenuation of Bismuth-Based Nanoprobes for Accurate Diagnosis of Liver Fibrosis

Timely detection of liver fibrosis by X-ray computed tomography (CT) can prevent its progression to fatal liver diseases. However, it remains quite challenging because conventional CT can only identify the difference in density instead of X-ray attenuation characteristics. Spectral CT can generate monochromatic imaging to specify X-ray attenuation characteristics of the scanned matter. Herein, an X-ray energy-dependent attenuation strategy originated from bismuth (Bi)-based nanoprobes (BiF3 @PDA@HA) is proposed for the accurate diagnosis of liver fibrosis. Bi element in BiF3 @PDA@HA can exhibit characteristic attenuation depending on different levels of X-ray energy via spectral CT, and that is challenging for conventional CT. In this study, selectively accumulating BiF3 @PDA@HA nanoprobes in the hepatic fibrosis areas can significantly elevate CT value for 40 Hounsfield units on 70 keV monochromatic images, successfully differentiating from healthy livers and achieving the diagnosis of liver fibrosis. Furthermore, the enhancement produced by the BiF3 @PDA@HA nanoprobes in vivo increases as the monochromatic energy decreases from 70 to 40 keV, optimizing the conspicuity of the diseased areas. As a proof of concept, the strategically designed nanoprobes with energy-dependent attenuation characteristics not only expand the scope of CT application, but also hold excellent potential for precise imaging-based disease diagnosis.

Dual Gate-Controlled Therapeutics for Overcoming Bacterium-Induced Drug Resistance and Potentiating Cancer Immunotherapy

The presence of bacteria in the tumor can cause cancer resistance to chemotherapeutics. To fight against bacterium-induced drug resistance, herein we design self-traceable nanoreservoirs that are simultaneously loaded with gemcitabine (an anticancer drug) and ciprofloxacin (an antibiotic) and are decorated with hyaluronic acid for active tumor targeting. The nanoreservoirs have a pH-sensitive gate and an enzyme-responsive gate that can be opened in the acidic and hyaluronidase-abundant tumor microenvironment to control drug release rates. Moreover, the nanoreservoirs can specifically target the tumor regions without eliciting evident toxicity to normal tissues, kill the intratumoral bacteria, and inhibit the tumor growth even in the presence of the bacteria. Unexpectedly, the nanoreservoirs can activate T cell-mediated immune responses through promoting antigen-presenting dendritic cell maturation and depleting immunosuppressive myeloid-derived suppressor cells in bacterium-infected tumors.

Hyaluronic acid-graphene quantum dot nanocomposite: Potential target drug delivery and cancer cell imaging

Nowadays, the use of nanoparticle-based drug delivery systems has received much more attention. In this regard, here, graphene quantum dots (GQD) were used as drug carriers as well as imaging agents for cancer cells. In order to optimize the dose of the drug and reduce its side effects for healthy cells, hyaluronic acid was decorated on the surface of GQD to target cancer cells. The morphology and size of the synthesized nanoparticles alone and conjugated with hyaluronic acid were investigated using scanning electron microscopy (SEM) and transmission electron microscopy (TEM); TEM images revealed a particles size of ∼5.67 and ∼8.69 nm, respectively. In the presence of 1-ethyl-3-[3(dimethylamino)propyl]carbodiimide hydrochloride/N-hydroxysuccinimide (EDC/NHS), hyaluronic acid was bounded to dopamine hydrochloride and was prepared to react with GQD. After synthesis of graphene quantum dot-hyaluronic acid nanocomposite, curcumin (CUR) as a drug model was loaded on the synthesized nanocarriers, and its loading percentage was measured. The results showed that 98.02% of the drug was loaded on the nanocarriers. Also, the conjugation of each agent on the nanocarrier was approved by photoluminescence spectroscopy, Fourier transform infrared spectroscopy (FTIR), and UV-visible absorption techniques, and the results showed that the reactions were performed correctly. The effect of GQD, graphene quantum dot-hyaluronic acid, CUR, graphene quantum dot-hyaluronic acid-CUR on the viability of HeLa and L929 cells was evaluated by the MTT test. The results showed that the synthesized nanocarrier is completely biocompatible, and the drug nanocarriers reduce HeLa cell viability significantly due to the mediation of hyaluronic acid-CD44 for drug cell uptake. Simultaneously with drug delivery, the other goal of these nanocarriers is to image cancer cells by emitting fluorescent light. Fluorescent microscopy showed that these nanocarriers were adsorbed on HeLa cells, unlike L929 cells.

Non-Invasive Topical Drug-Delivery System Using Hyaluronate Nanogels Crosslinked via Click Chemistry

Hyaluronate (HA) has been widely investigated for noninvasive topical drug delivery of chemical drugs and biopharmaceuticals. However, previous noninvasive delivery systems have been facilitated mostly by chemical conjugation of drugs with HA, which can cause reduced therapeutic efficacy and safety issues in chemically modified drugs. Here, HA nanogels were synthesized by crosslinking via "click" chemistry for noninvasive topical delivery of a model drug without chemical modification. The model-drug-encapsulating HA nanogels could be uptaken to the skin melanoma cells in vitro by HA-mediated endocytosis. In addition, histological analysis showed that HA nanogels could be topically delivered to the deep skin and tongue tissues through the noninvasive delivery routes. Taken together, HA nanogels could be effectively used for the noninvasive topical delivery of various therapeutic drugs.

Fluorescent nanotechnology for in vivo imaging

Fluorescent imaging in living animals gives an intuitive picture of the dynamic processes in the complex environment within a living being. However, animal tissues present a substantial barrier and are opaque to most wavelengths of visible light. Fluorescent nanoparticles (NPs) with new photophysical characteristics have shown excellent performance for in vivo imaging. Hence, fluorescent NPs have been widely studied and applied for the detection of molecular and biological processes in living animals. In addition, developments in the area of nanotechnology have allowed materials to be used in intact animals for disease detection, diagnosis, drug delivery, and treatment. This review provides information on the different types of fluorescent particles based on nanotechnology, describing their unique individual properties and applications for detecting vital processes in vivo. The development and application of new fluorescent NPs will provide opportunities for in vivo imaging with better penetration, sensitivity, and resolution. This article is categorized under: Diagnostic Tools > in vivo Nanodiagnostics and Imaging.

Microfluidic chip enabled one-step synthesis of biofunctionalized CuInS2/ZnS quantum dots

Biofunctionalized quantum dots (QDs) are effective target fluorescent labels for bioimaging. However, conventional synthesis of biofunctionalized I-III-VI core-shell CuInS2/ZnS QDs requires complex bench-top operations, resulting in limited product performance and variety, and is not amenable to a 'one-step' approach. In this work, we have successfully demonstrated a fully automated method for preparing denatured bovine serum albumin (dBSA)-CuInS2/ZnS QDs by introducing microfluidic (MF) chips to synthesize biofunctionalized QDs, hence establishing a 'one-step' procedure. We have also studied and optimized the reaction synthesis parameters. The emission wavelength of the dBSA-CuInS2/ZnS QDs is located in the near-infrared range and can be tuned from 650 to 750 nm by simply varying the reaction parameters. In addition, the 'one-step'-synthesized dBSA-CuInS2/ZnS QDs have a long average fluorescence lifetime of 153.76 ns and a small particle size of 5 ± 2 nm. To demonstrate the applicability of the 'one-step'-synthesized dBSA-CuInS2/ZnS QDs in bioimaging studies, we modified the QDs with folic acid and hyaluronic acid, and then performed target bioimaging and cytotoxicity tests on macrophages, liver cancer cells and pancreatic cancer cells. The cell images show that the red emission signals originate from the QDs, which indicates that the dBSA-CuInS2/ZnS QDs prepared by the MF approach are suitable optical contrast agents for target bioimaging. This 'one-step' MF-based QD synthesis approach could serve as a rapid, cost-effective, and small-scale nanocrystal production platform for complex QD formulations for a wide range of bioapplications.

Ursolic acid reverses liver fibrosis by inhibiting interactive NOX4/ROS and RhoA/ROCK1 signalling pathways

Liver fibrosis is the reversible deposition of extracellular matrix (ECM) and scar formation after liver damage by various stimuli. The interaction between NOX4/ROS and RhoA/ROCK1 in liver fibrosis is not yet clear. Ursolic acid (UA) is a traditional Chinese medicine with anti-fibrotic effects, but the molecular mechanism underlying these effects is still unclear. We investigated the interaction between NOX4/ROS and RhoA/ROCK1 during liver fibrosis and whether these molecules are targets for the anti-fibrotic effects of UA. First, we confirmed that UA reversed CCl4-induced liver fibrosis. In the NOX4 intervention and RhoA intervention groups, related experimental analyses confirmed the decrease in CCl4-induced liver fibrosis. Next, we determined that the expression of NOX4 and RhoA/ROCK1 was decreased in UA-treated liver fibrotic mice. Furthermore, RhoA/ROCK1 expression was decreased in the NOX4 intervention group, but there was no significant change in the expression of NOX4 in the RhoA intervention group. Finally, we found that liver fibrotic mice showed a decline in their microbiota diversity and abundance, a change in their microbiota composition, and a reduction in the number of potential beneficial bacteria. However, in UA-treated liver fibrotic mice, the microbiota dysbiosis was ameliorated. In conclusion, the NOX4/ROS and RhoA/ROCK1 signalling pathways are closely linked to the development of liver fibrosis. UA can reverse liver fibrosis by inhibiting the NOX4/ROS and RhoA/ROCK1 signalling pathways, which may interact with each other.

Targeted delivery of hyaluronic acid nanomicelles to hepatic stellate cells in hepatic fibrosis rats

Hepatic fibrosis is one kind of liver diseases with a high mortality rate and incidence. The activation and proliferation of hepatic stellate cells (HSCs) is the most fundamental reason of hepatic fibrosis. There are no specific and effective drug delivery carriers for the treatment of hepatic fibrosis at present. We found that when hepatic fibrosis occurs, the expression of CD44 receptors on the surface of HSCs is significantly increased. Based on this finding, we designed silibinin-loaded hyaluronic acid (SLB-HA) micelles to achieve the treatment of hepatic fibrosis. Meanwhile, we constructed liver fibrosis rat model using Sprague–Dawley rats. We demonstrated that HA micelles had specific uptake to HSCs in vitro while avoiding the distribution in normal liver cells and the phagocytosis of macrophages. Importantly, HA micelles showed a significant liver targeting effect in vivo, especially in fibrotic liver which highly expressed CD44 receptors. In addition, SLB-HA micelles could selectively kill activated HSCs, having an excellent anti-hepatic fibrosis effect in vivo and a significant sustained release effect, and also had a good biological safety and biocompatibility. Overall, HA micelles represented a novel nanomicelle system which showed great potentiality in anti-hepatic fibrosis drugs delivery.

Innovative Nanotechnological Formulations to Reach the Hepatic Stellate Cell

Purpose of Review

Treatment of liver fibrosis benefits from hepatic stellate cell (HSC)-specific delivery. Since the description of first carrier to HSC, many developments have taken place in this area. The purpose is to give an overview of the different carriers and homing moieties that are available for HSC targeting and illustrate the opportunities and hurdles they provide.

Recent Findings

There is a growing number of homing devices to deliver drugs to HSC, and options to deliver siRNA to HSC have emerged. Other developments include controlling corona formation, development of linker technology, and design of theranostic approaches. We are on the eve of reaching the clinic with innovative HSC-specific compounds.

Summary

An overview of different core molecules is presented together with an overview of targeting strategies toward different receptors on HSC, providing a versatile toolbox. Many therapeutics, ranging from small chemical entities and proteins to RNA- or DNA-modulating substances, have already been incorporated in these constructs in the recent years.

Bio-application of Inorganic Nanomaterials in Tissue Engineering

Inorganic nanomaterials or nanoparticles (INPs) have drawn high attention for their usage in the biomedical field. In addition to the facile synthetic and modifiable property of INPs, INPs have various unique properties that originate from the components of the INPs, such as metal ions that are essential for the human body. Apart from their roles as components of the human body, inorganic materials have unique properties, such as magnetic, antibacterial, and piezoelectric, so that INPs have been widely used as either carriers or inducers. However, most of the bio-applicable INPs, especially those consisting of metal, can cause cytotoxicity. Therefore, INPs require modification to alleviate the harmful effect toward the cells by controlling the release of metal ions from INPs. Even though many attempts have been made to modify INPs, many things, including the side effects of INPs, still remain as obstacles in the bio-application, which need to be elucidated. In this chapter, we introduce novel INPs in terms of their synthetic method and bio-application in tissue engineering.

Preparation of paclitaxel-folic acid functionalized gelatin grafted mesoporous hollow carbon nanospheres for enhancing antitumor effects toward liver cancer (SMMC-7721) cell lines

Folic acid functionalized gelatin-coated mesoporous hollow carbon nanospheres (FGMCN) were synthesized and applied to enhance the antitumor curative effect of paclitaxel (PTX) for human liver cancer cell lines (SMMC-7721). PTX was loaded in FGMCN by the adsorption method and the PTX-loaded samples (PTX-FGMCN) had a drug content of 29.8 ± 1.06%. The PTX-FGMCN with a sustained release effect was characterized by X-ray diffraction and differential scanning calorimeter in order to analyze the PTX state in FGMCN. In vitro cell experiments showed that FMHSN improves the uptake of PTX and promotes apoptosis due to the nano-targeting effect of FMHSN. An in vivo tumor bearing experiment in mice indicated that the PTX-FGMCN significantly inhibited the growth of tumors. All of these results suggested that the PTX-FGMCN may be an effective anti-hepatoma drug in the future.

Hyaluronan-based delivery of therapeutic oligonucleotides for treatment of human diseases

INTRODUCTION

Oligonucleotide therapeutics such as antisense oligonucleotides and siRNA requires chemical modifications and nano-sized carriers to circumvent stability problems in vivo, to reach target tissues, and to overcome tissue and cellular barriers. Hyaluronic acid (HA), already utilized in drug delivery and tissue engineering, possess properties that are useful to solve these problems and achieve full potential of oligonucleotide therapeutics.

AREAS COVERED

Complexes of oligonucleotide therapeutics with HA are discussed in terms of interactions providing the complexes formation and genes targeted by the therapeutics to cure diseases such as cancer, atherosclerosis, liver cirrhosis, and inflammation. The achieved therapeutic effects are rationalized as consequences of biodistribution, cell internalization and endosomal escape provided by HA.

EXPERT OPINION

Design of electrostatic, coordination, and hydrophobic interactions as well as covalent conjugation between oligonucleotide drugs, HA macromolecules and intermediate ligands are crucial for carrier-cargo association and dissociation under different conditions to impart oligonucleotides stability in vivo, their accumulation in diseased organs, cellular uptake, and dissociation in cytoplasm intact. These are the delivery factors that provides eventual complex formation of oligonucleotide therapeutics with their mRNA, microRNA, or protein targets. Elucidation of the impact of structural parameters of oligonucleotide/HA complexes on their therapeutic effect in vivo is important for the future rational design of the delivery agents.

Golgi Apparatus-Targeted Chondroitin-Modified Nanomicelles Suppress Hepatic Stellate Cell Activation for the Management of Liver Fibrosis

Liver fibrosis is a serious liver disease associated with high morbidity and mortality. The activation of hepatic stellate cells (HSCs) and the overproduction of extracellular matrix proteins are key features during disease progression. In this work, chondroitin sulfate nanomicelles (CSmicelles) were developed as a delivery system targeting HSCs for the treatment of liver fibrosis. CS-deoxycholic acid conjugates (CS-DOCA) were synthesized via amide bond formation. Next, retinoic acid (RA) and doxorubicin (DOX) were encapsulated into CSmicells to afford a DOX+RA-CSmicelles codelivery system. CSmicelles were selectively taken up in activated HSCs and hepatoma (HepG2) cells other than in normal hepatocytes (LO2), the internalization of which was proven to be mediated by CD44 receptors. Interestingly, DOX+RA-CSmicelles preferentially accumulated in the Golgi apparatus, destroyed the Golgi structure, and ultimately downregulated collagen I production. Following tail-vein injection, DOX+RA-CSmicelles were delivered to the cirrhotic liver and showed synergistic antifibrosis effects in the CCl₄-induced fibrotic rat model. Further, immunofluorescence staining of dissected liver tissues revealed CD44-specific delivery of CS derivatives to activated HSCs. Together, our results demonstrate the great potential of CS based carrier systems for the targeted treatment of chronic liver diseases.

Targeted Delivery of Paclitaxel in Liver Cancer Using Hyaluronic Acid Functionalized Mesoporous Hollow Alumina Nanoparticles

Hyaluronic acid functionalized mesoporous hollow alumina nanoparticles (HMHA) were used as a tumor-targeted delivery carrier for liver cancer therapy. Paclitaxel (PAC) incorporated in the carrier by the adsorption method was analyzed by X-ray diffraction and differential scanning calorimetry. PAC was found to be in an amorphous state. The hyaluronic acid coated on the surface of mesoporous hollow alumina nanoparticles (MHA) regulated the drug release rate and the loaded samples obtained a sustained drug release. In vitro experiments demonstrated that paclitaxel-hyaluronic acid functionalized mesoporous hollow alumina nanoparticles (PAC-HMHA) had a high cellular uptake, which increased the drug level in tumor tissues and was beneficial to promote apoptosis. An in vivo tumor inhibition rate study demonstrated that PAC-HMHA (64.633 ± 4.389%) had a better antitumor effect than that of paclitaxel-mesoporous alumina nanoparticles (PAC-MHA, 56.019 ± 6.207%) and pure PAC (25.593 ± 4.115%). Therefore it can be concluded that PAC-HMHA are a prospective tumor-targeted delivery medium and can be useful for future cancer therapy.

Targeted Drug Delivery to Hepatic Stellate Cells for the Treatment of Liver Fibrosis

Liver fibrosis is caused by excessive accumulation of extracellular matrix during chronic liver injuries. Although clinical evidence suggests that liver fibrosis can be reversed, there is no standard therapy for liver fibrosis. Moreover, there is a lack of diagnostic tools to detect early-stage liver fibrosis. Activation of hepatic stellate cells (HSCs) is the key step during liver fibrogenesis, and its mechanism has been extensively studied by various cell culture and animal models. Targeted delivery of therapeutic agents to activated HSCs is therefore critical for the successful treatment of liver fibrosis. A number of protein markers have been found to be overexpressed in activated HSCs, and their ligands have been used to specifically deliver various antifibrotic agents. In this review, we summarize these HSC-specific protein markers and their ligands for targeted delivery of antifibrotic agents.

The advanced role of carbon quantum dots in nanomedical applications

Carbon quantum dots (CQDs) have emerged as a potential material in the diverse fields of biomedical applications due to their numerous advantageous properties including fluorescence, water solubility, biocompatibility, low toxicity, small size and ease of modification, inexpensive scale-up production, and versatile conjugation with other nanoparticles. Thus, CQDs became a preferable choice in various biomedical applications such as nanocarriers for drugs, therapeutic genes, photosensitizers, and antibacterial molecules. Further, their potentials have also been verified in multifunctional diagnostic platforms, cellular and bacterial bio-imaging, development of theranostics nanomedicine, etc. This review provides a concise insight into the progress and evolution in the field of CQD research with respect to methods/materials available in bio-imaging, theranostics, cancer/gene therapy, diagnostics, etc. Further, our discussion is extended to explore the role of CQDs in nanomedicine which is considered to be the future of biomedicine. This study will thus help biomedical researchers in tapping the potential of CQDs to overcome various existing technological challenges.

Biomarkers-based Biosensing and Bioimaging with Graphene for Cancer Diagnosis

At the onset of cancer, specific biomarkers get elevated or modified in body fluids or tissues. Early diagnosis of these biomarkers can greatly improve the survival rate or facilitate effective treatment with different modalities. Potential nanomaterial-based biosensing and bioimaging are the main techniques in nanodiagnostics because of their ultra-high selectivity and sensitivity. Emerging graphene, including two dimensional (2D) graphene films, three dimensional (3D) graphene architectures and graphene hybrids (GHs) nanostructures, are attracting increasing interests in the field of biosensing and bioimaging. Due to their remarkable optical, electronic, and thermal properties; chemical and mechanical stability; large surface area; and good biocompatibility, graphene-based nanomaterials are applicable alternatives as versatile platforms to detect biomarkers at the early stage of cancer. Moreover, currently, extensive applications of graphene-based biosensing and bioimaging has resulted in promising prospects in cancer diagnosis. We also hope this review will provide critical insights to inspire more exciting researches to address the current remaining problems in this field.

Surface plasmon resonance enhancement of photoluminescence intensity and bioimaging application of gold nanorod@CdSe/ZnS quantum dots

Biological applications of core/shell near-infrared quantum dots (QDs) have attracted broad interest due to their unique optical and chemical properties. Additionally, the use of multifunctional nanomaterials with near-infrared QDs and plasmonic functional nanoparticles are promising for applications in electronics, bioimaging, energy, and environmental-related studies. In this work, we experimentally demonstrate how to construct a multifunctional nanoparticle comprised of CdSe/ZnS QDs and gold nanorods (GNRs) where the GNRs were applied to enhance the photoluminescence (PL) of the CdSe/ZnS QDs. In particular, we have obtained the scattering PL spectrum of a single CdSe/ZnS QD and GNR@CdSe/ZnS nanoparticle and comparison results show that the CdSe/ZnS QDs have an apparent PL enhancement of four-times after binding with GNRs. In addition, in vitro experimental results show that the biostability of the GNR@CdSe/ZnS nanoparticles can be improved by using folic acid. A bioimaging study has also been performed where GNR@CdSe/ZnS nanoparticles were used as an optical process for MCF-7 breast cancer cells.

Targeted cellular delivery of robust enzyme nanoparticles for the treatment of drug-induced hepatotoxicity and liver injury

Direct delivery of proteins into cells has been considered an effective approach for treating the protein-related diseases. However, clinical use of proteins has still been limited due to their instability in the blood and poor membrane permeability. To achieve an efficient cellular delivery of the protein to target cells via a systemic administration, a multifunctional carrier system having desirable stability both in the blood stream and the cells, specific cell-targeting property and endosomal escape functions may be required. In this study, we prepared a catalytic nanoparticle containing an active enzyme by cross-tethering multiple superoxide dismutase (SOD) molecules with catechol-derivatized hyaluronic acid (HA). The permeable shell of hydrophilic HA chains effectively protects the enzyme from degradation in the blood after intravenous administration and provides an additional function for targeting hepatocytes expressing HA receptor (CD44). The structure and catalytic activity of the enzyme molecules in the nanoparticle were not significantly compromised in the nanoparticle. In addition, ultra-small calcium phosphate nanoparticles (USCaP, 2-5 nm) were crystalized and decorated on the surface of the nanoparticle for the efficient endosomal escape after cellular uptake. The SOD-containing nanoparticle fortified with USCaP was used for the treatment of acetaminophen (APAP)-induced fulminant hepatotoxicity and liver injury. The nanoparticle achieved the efficient hepatic cellular delivery of SOD via a systemic administration and resulted in efficient removal of reactive oxygen species (ROS) in the liver and remarkable improvement of APAP-induced hepatotoxicity and liver injury in animals. STATEMENT OF SIGNIFICANCE: Despite the enormous therapeutic potential, the intracellular delivery of proteins has been limited due to their poor membrane permeability and stability. In this study, we demonstrated an active enzyme-containing nanoparticle functionalized by hyaluronic acid and ultra-small size calcium phosphate nanoparticles (2-5 nm) for targeted cellular delivery of superoxide dismutase (SOD). The nanoparticle was designed to integrate all the essential functions, including serum stability, target specificity, and endosomal escape capability, for a systemic delivery of a therapeutic protein to the cells of the liver tissue. The intravenous administration of the nanoparticle efficiently removes reactive oxygen species (ROS) in the liver and remarkably improves the drug-induced hepatotoxicity and the progress of fulminant liver injury in an acetaminophen-overdose animal model.

Hepatic stellate cell-targeted therapy for hepatic fibrosis

Hepatic fibrosis is the ultimate pathological feature of all forms of chronic hepatic damage. There is currently no clinical cure for advanced liver fibrosis. Activation and proliferation of hepatic stellate cells (HSCs) is a key step in the development of liver fibrosis, and therefore, HSCs are target cells for hepatic fibrosis treatment. Targeted delivery of drugs to activated HSCs would increase the drug concentration in the liver at the sites of active fibrogenesis and avoid undesirable systemic effects. Mannose 6-phosphate modified human serum albumin, vitamin A, and hyaluronic acid are three kinds of the most investigated carriers that deliver drugs to the activated HSCs specifically. Conjugation of these carriers with molecules with anti-fibrosis activity such as angiotensin receptor blockers, activin-like kinase 5 inhibitors, Rho-kinase inhibitors, small interfering RNAs, hepatocyte growth factor gene, or nitrogen monoxide can lead to specific distribution and effects in HSCs. This review will focus on these preclinical developments of HSCs-targeted drug conjugates for the treatment of liver fibrosis.

Gadolinium-Labeled Biodegradable Dendron-Hyaluronic Acid Hybrid and Its Subsequent Application as a Safe and Efficient Magnetic Resonance Imaging Contrast Agent

Novel magnetic resonance imaging (MRI) contrast agents with high sensitivity and good biocompatibility are required for the diagnosis of cancer. Herein, we prepared and characterized the gadolinium [Gd(III)]-labeled peptide dendron-hyaluronic acid (HA) conjugate-based hybrid (dendronized-HA-DOTA-Gd) by combining the advantages of HA and the peptide dendron. The dendronized-HA-DOTA-Gd hybrid with 3.8% Gd(III) as weight percentage showed a negative zeta potential (-35 mV). The in vitro degradation results indicated that the dendronized-HA-DOTA-Gd hybrid degraded into products with low molecular weights in the presence of hyaluronidase. The dendronized-HA-DOTA-Gd hybrid showed a 3-fold increase in longitudinal relaxivity and much higher in vivo signal enhancement in 4T1 breast tumors of mice compared with clinical Magnevist (Gd-DTPA). The dendronized-HA-DOTA-Gd hybrid had a higher accumulation in tumors than Gd-DTPA; it was 2-3-fold after administration. Meanwhile, the polymeric hybrid resulted in low Gd(III) residue in the body compared with that of Gd-DTPA. The systematic biosafety evaluations, including blood compatibility and toxicity assessments, suggested that the dendronized-HA-DOTA-Gd hybrid exhibited good biocompatibility. Thus, the gadolinium-labeled and dendronized HA hybrid shows promise as a safe and efficient macromolecular MRI contrast agent based on high sensitivity, low residue content in the body, and good biosafety.

Gold nanocages with dual modality for image-guided therapeutics

Numerous studies have demonstrated that microRNAs are very important in cancer development and progression. However, the complex relationship between the size of microRNA delivery systems, cellular uptake, biodistribution and therapeutic efficiency remains unclear. Herein, we have successfully constructed a series of differently-sized microRNA delivery systems, miR-26a-loaded, hyaluronic acid-modified, polyetherimide-conjugated PEGylated gold nanocage ternary nanocomplexes (PPHAuNCs-TNCs), which can be monitored optically by fluorescence and photoacoustic tomography imaging. We evaluated the effect of the particle size on the cellular uptake and biodistribution in the BEL-7402 cell line in vitro and in the subcutaneous and orthotopic hepatocellular carcinoma (HCC) mouse models. Our findings showed that the cellular uptake and biodistribution were optimal for cancer therapy with the PPHAuNCs-30-TNCs (30 nm AuNCs in edge length) in comparison with their 50 nm and 70 nm counterparts. PPHAuNCs-30-TNCs could accumulate in the liver for a longer time in an orthotopic mouse model of HCC than that in normal mice and could considerably restrain tumor growth in an orthotopic HCC mouse model under near-infrared radiation. This study may provide insightful information for developing novel non-viral microRNA vectors, and PPHAuNCs-30-TNCs have great potential for application in tumor diagnosis and cancer therapy in the future.

Hyaluronan-Inorganic Nanohybrid Materials for Biomedical Applications

Nanomaterials, including gold, silver, and magnetic nanoparticles, carbon, and mesoporous materials, possess unique physiochemical and biological properties, thus offering promising applications in biomedicine, such as in drug delivery, biosensing, molecular imaging, and therapy. Recent advances in nanotechnology have improved the features and properties of nanomaterials. However, these nanomaterials are potentially cytotoxic and demonstrate a lack of cell-specific function. Thus, they have been functionalized with various polymers, especially polysaccharides, to reduce toxicity and improve biocompatibility and stability under physiological conditions. In particular, nanomaterials have been widely functionalized with hyaluronan (HA) to enhance their distribution in specific cells and tissues. This review highlights the most recent advances on HA-functionalized nanomaterials for biotechnological and biomedical applications, as nanocarriers in drug delivery, contrast agents in molecular imaging, and diagnostic agents in cancer therapy. A critical evaluation of barriers affecting the use of HA-functionalized nanomaterials is also discussed, and insights into the outlook of the field are explored.

Progress in rigid polysaccharide-based nanocomposites with therapeutic functions

Nanocomposites engineered by incorporating versatile nanoparticles into different bioactive β-glucan matrices display effective therapeutic functions.

Recent Advances in Stimuli-Responsive Release Function Drug Delivery Systems for Tumor Treatment

Benefiting from the development of nanotechnology, drug delivery systems (DDSs) with stimuli-responsive controlled release function show great potential in clinical anti-tumor applications. By using a DDS, the harsh side effects of traditional anti-cancer drug treatments and damage to normal tissues and organs can be avoided to the greatest extent. An ideal DDS must firstly meet bio-safety standards and secondarily the efficiency-related demands of a large drug payload and controlled release function. This review highlights recent research progress on DDSs with stimuli-responsive characteristics. The first section briefly reviews the nanoscale scaffolds of DDSs, including mesoporous nanoparticles, polymers, metal-organic frameworks (MOFs), quantum dots (QDs) and carbon nanotubes (CNTs). The second section presents the main types of stimuli-responsive mechanisms and classifies these into two categories: intrinsic (pH, redox state, biomolecules) and extrinsic (temperature, light irradiation, magnetic field and ultrasound) ones. Clinical applications of DDS, future challenges and perspectives are also mentioned.

Targeted systemic mesenchymal stem cell delivery using hyaluronate - wheat germ agglutinin conjugate

A variety of receptors for hyaluronate (HA), a natural linear polysaccharide, were found in the body, which have been exploited as target sites for HA-based drug delivery systems. In this work, mesenchymal stem cells (MSCs) were surface-modified with HA - wheat germ agglutinin (WGA) conjugate for targeted systemic delivery of MSCs to the liver. WGA was conjugated to HA by coupling reaction between aldehyde-modified HA and amine group of WGA. The conjugation of WGA to HA was corroborated by gel permeation chromatography (GPC) and the successful surface modification of MSCs with HA-WGA conjugate was confirmed by confocal microscopy. The synthesized HA-WGA conjugate could be incorporated onto the cellular membrane by agglutinating the cell-associated carbohydrates. Fluorescent imaging for in vivo biodistribution visualized the targeted delivery of the HA-WGA/MSC complex to the liver after intravenous injection. This new strategy for targeted delivery of MSCs using HA-WGA conjugate might be successfully exploited for various regenerative medicines including cell therapy.

Constructing aptamer anchored nanovesicles for enhanced tumor penetration and cellular uptake of water soluble chemotherapeutics

Polymersomes represent a promising pharmaceutical vehicle for the delivery of hydrophilic therapeutic agents. However, modification of polymersomes with molecules that confer targeting functions remains challenging because of the strict requirements regarding the weight fractions of the hydrophilic and hydrophobic block polymers. In this study, based on the compatibility between cholesterol and polymeric carriers, polymersomes self-assembled by amphiphilic graft polyphosphazenes were endowed with a targeting function by incorporating the cholesterol-linked aptamer through a simple dialysis method. The aqueous interior of the polymersomes was employed to encapsulate water-soluble doxorubicin hydrochloride. In vivo experiments in tumor-bearing mice showed that the aptamer-anchored vesicle targeted accumulation at the tumor site, favorable penetration through tumor tissue, and incremental endocytosis into tumor cells. Correspondingly, the aptamer-anchored vesicle decreased systemic toxicity and effectively suppressed the growth of subcutaneous MCF-7 xenografts. These findings suggested that vesicles modified with targeted groups via hydrophobic supermolecular interactions could provide a platform for selective delivery of hydrophilic drug.

STATEMENT OF SIGNIFICANCE

Polymersomes have represented a promising type of pharmaceutical vehicles due to their predominant physical properties. However, it is still a challenge to endow polymersomes with active target function because of strict requirements of the weight fractions of hydrophilic polymer block to hydrophobic one. In this research, by taking advantage of the supermolecular interactions between amphiphilic graft polyphosphazene and cholesterol which was linked to aptamer AS1411, we prepared a targeted functional polymersome (PEP-DOX·HCl-Ap) through a simple method with high loading of water soluble anti-cancer drug doxorubicin hydrochloride. The in vivo experiments in MCF-7 tumor-bearing mice demonstrated several advantages of PEP-DOX·HCl-Ap vesicle such as prolonged circulation time in blood, targeted accumulation at tumor site, permeation through the tumor tissue and incremental endocytosis by tumor cells, which consequently resulted in the significantly improved anti-cancer efficacy. Moreover, this novel polymersome designed in this study has built a research platform to achieve targeted delivery of hydrophilic chemotherapeutics for cancer therapy.