Self-assembled Drug Delivery Systems Research Articles

Constructing a hydrogel based on self-assembly properties of glycyrrhizic acid: A drug delivery system with digestive tract responsive

Glycyrrhizic acid (GA), an amphiphilic compound, is known for its natural sweetness and excellent self-assembly properties. Based on its self-assembled formulation forming ability, GA has been used as drug carriers and absorption enhancers, thereby altering the in vivo absorption kinetic processes of loaded drugs. This study mainly focuses on the influence of the GA self-assembled drug delivery system on the solubility, stability, and in vitro release of various active ingredients in traditional Chinese medicine, especially simulating the physiological rhythms and environment of in vivo absorption. Our findings indicate that GA has a significant solubilizing effect on poorly water-soluble components. The inclusion of GA improves the stability of the majority of the measured components to different extents in the digestive tract. Furthermore, in vitro release studies have demonstrated that the GA hydrogel system effectively slows drug release and is also enterosoluble, indicating responsiveness to the digestive tract, which contributes to stable concentrations of the drug in the blood. To sum up, the GA self-assembled drug delivery system can enhance solubility and stability to varying degrees by altering the in vivo absorption kinetics of representative active ingredients, exhibiting drug sustained release and self-assembly system enteric-like characteristics in different physiological environments. This indicates that the drug delivery system formed by GA through self-assembly can interact with the digestive tract environment, thus enhancing the in vivo bioavailability of drugs by influencing their biopharmaceutical properties.

Polymer-Based Self-Assembled Drug Delivery Systems for Glaucoma Treatment: Design Strategies and Recent Advances.

Glaucoma has become the world's leading cause of irreversible blindness, and one of its main characteristics is high intraocular pressure. Currently, the non-surgical drug treatment scheme to reduce intraocular pressure is a priority method for glaucoma treatment. However, the complex and special structure of the eye poses significant challenges to the treatment effect and safety adherence of this drug treatment approach. To address these challenges, the application of polymer-based self-assembled drug delivery systems in glaucoma treatment has emerged. This review focuses on the utilization of polymer-based self-assembled structures or materials as important functional and intelligent carriers for drug delivery in glaucoma treatment. Various drug delivery systems, such as eye drops, hydrogels, and contact lenses, are discussed. Additionally, the review primarily summarizes the design strategies and methods used to enhance the treatment effect and safety compliance of these polymer-based drug delivery systems. Finally, the discussion delves into the new challenges and prospects of employing polymer-based self-assembled drug delivery systems for the treatment of glaucoma.

A proof-of-concept study of coupled supercritical CO2-assisted processes to produce solid self-assembled drug delivery systems (S-SADDS)

The development of innovative drug delivery systems is currently under intense consideration to overcome bioavailability issues of poorly water-soluble drugs. Among the many existing delivery systems, self-assembled drug delivery systems (SADDS) are of great interest. Solid Lipid Nanoparticles (SLN), which are part of SADDS, have been widely studied in the pharmaceutical field since they are biodegradables and biocompatibles. However, stability of SLN suspension over time is limited and quick drug released were frequently observed. The development of solid SADDS (S- SADDS), to produce an on-demand delivery system, through a one-step production process has been designed to overcome these issues. The coupling of both Supercritical Carbon Dioxide (scCO2) assisted RESS and SAS processes (RESS/SAS) have been proposed as a proof-of-concept. This study was carried out in three steps: (i) the development and adjustment of operating conditions to produce SLN suspension using solvent injection process, (ii) the optimization of the formulation to produce SLN with a mean particle size diameter close to 100 nm and stable at least 24 h, (iii) the transposition of the SLN formulation composition into the RESS/SAS coupled process for the production of S-SADDS. SLN composed of stearic acid, PVP K30, phosphatidylcholine and nifedipine, with an average size under 100 nm and a zeta potential about −35 mV were obtained from the preliminary study. These results allowed the transposition of the optimal formulation into RESS/SAS crystallization process. The developed RESS/SAS scCO2-assisted processes demonstrate the simultaneous crystallization of a self-assembled formulation in a one step process. A control of operating conditions was also demonstrated through the generation of S- SADDS containing desired amount of nifedipine. The proof-of-concept process studied, seems to be very promising tool for the generation of complex solids, intermediate products or for the development of innovative drug delivery systems.

Glucose-derived carbon dots for targeted delivery of doxorubicin in cancer therapy

In the present research work, a carbon-dot (CD)-based self-assembled drug delivery system for the delivery of doxorubicin in cancer cells was developed.

Escherichia coli as a New Platform for the Fast Production of Vault-like Nanoparticles: An Optimized Protocol

Vaults are protein nanoparticles that are found in almost all eukaryotic cells but are absent in prokaryotic ones. Due to their properties (nanometric size, biodegradability, biocompatibility, and lack of immunogenicity), vaults show enormous potential as a bio-inspired, self-assembled drug-delivery system (DDS). Vault architecture is directed by self-assembly of the "major vault protein" (MVP), the main component of this nanoparticle. Recombinant expression (in different eukaryotic systems) of the MVP resulted in the formation of nanoparticles that were indistinguishable from native vaults. Nowadays, recombinant vaults for different applications are routinely produced in insect cells and purified by successive ultracentrifugations, which are both tedious and time-consuming strategies. To offer cost-efficient and faster protocols for nanoparticle production, we propose the production of vault-like nanoparticles in Escherichia coli cells, which are still one of the most widely used prokaryotic cell factories for recombinant protein production. The strategy proposed allowed for the spontaneous encapsulation of the engineered cargo protein within the self-assembled vault-like nanoparticles by simply mixing the clarified lysates of the producing cells. Combined with well-established affinity chromatography purification methods, our approach contains faster, cost-efficient procedures for biofabrication in a well-known microbial cell factory and the purification of "ready-to-use" loaded protein nanoparticles, thereby opening the way to faster and easier engineering and production of vault-based DDSs.

The discovery of berberine erythrocyte-hemoglobin self-assembly delivery system: a neglected carrier underlying its pharmacokinetics

Berberine (BBR) has extremely low concentration and high tissue distribution. However, current pharmacokinetic studies predominantly focus on its concentration in plasma, which could hardly make a comprehensive understanding of its pharmacokinetic process. This study made a pioneering endeavor to explore the erythrocyte-hemoglobin (Hb) self-assembly system of BBR by exploring the interaction of BBR with erythrocyte and the combination of BBR with Hb. Results showed that BBR had a low bioavailability (C0 = 2.833 μg/mL via intravenous administration of 2.5 mg/kg BBR and Cmax = 0.260 μg/mL via oral administration of 400 mg/kg BBR). Besides, BBR achieved higher concentrations in erythrocytes than plasma, and the erythrocytes count and Hb content were significantly decreased after intravenous administration. Hemolysis rate indicated the BBR-erythrocyte system (with 2% erythrocytes) was relatively stable without hemolysis at the concentration of 1.00 mg/mL. And the maximum percentage of drug loading was 100% when the BBR-erythrocyte concentration was 0.185 μg/mL. Furthermore, incubation of BBR and erythrocytes resulted in internalization of the erythrocyte membrane and the formation of intracellular vacuoles. The thermodynamic parameters indicated that the binding process of bovine hemoglobin (BHB) and BBR was spontaneous. UV-vis absorption spectra, synchronous fluorescence, circular dichroism and Raman spectra collectively indicated that BBR showed strong binding affinity toward BHB and affected the molecular environment of residues like tryptophan and tyrosine in BHB, resulting in the conformational changes of its secondary and tertiary structure. Molecular docking indicated BBR interacted with Arg-141 residue of BHB via hydrogen bond with the bond length of 2.55 Å. The ΔG value of the BHB-BBR system was −31.79 kJ/mol. Molecular dynamics simulation indicated the root mean square derivation of BBR-BHB was <0.025 nm, suggestive of stable conformation. Cumulatively, there was an erythrocyte-Hb self-assembled drug delivery system after oral or intravenous administration of BBR, which conceivably gained novel insight into the discrepancy between the extremely low plasma concentration and relatively high tissue concentration of BBR.

Self-Assembled Amphotericin B Pharmacosome-Like Vesicles Derived from Lipid-Based Microtubes: A Model Carrier to Further Explore

Background: Self-assembled drug delivery systems are of much interest since they can be produced by simple low cost and solvent-free procedures. Pharmacosomes are supramolecularstructured nanocarriers with benefits for drug stability and targeting delivery. Amphotericin B (AmB) still remains an important agent for the treatment of invasive mold infections, e.g invasive aspergillosis, although the challenge for new formulations is still prevailing due to high rates of toxicity. Objective: We have previously reported the incorporation of AmB into 12-hydroxystearic acid lipidbased microtubes (MTs) for topical use, herein we report the ability of AmB-MTs to self-assemble into vesicles upon dilution. Methods: AmB-MTs with different drug concentrations (1, 3, 5 mg/ml) were prepared, and size determination was carried out for different dilutions. Morphology was evaluated by microscopy. In vitro cytotoxicity was evaluated in Vero cells and in vitro activity against Aspergillus fumigatus and Aspergillus flavus was assessed. Results: AmB-MTs closed upon dilution to form vesicles ranging from 200 nm to 1μm. AmB MIC (Minimum inhibitory concentration) for both Aspergillus species was 0.0625 and 0.125 μg/ml for dispersion and reconstituted lyophilized, respectively. Conclusion: AmB pharmacosome-like vesicles are smaller structures than MTs may thus be favourable for other delivery routes. We assume that this kind of pharmacosomes-like carrier is a promising model for the obtention of new vesicular carriers based on lipid MTs.

Supramolecular self-assembled drug delivery system (SADDs) of vancomycin and tocopherol succinate as an antibacterial agent: in vitro, in silico and in vivo evaluations

In this study self-assembled drug delivery system (SADDs) composed of a hydrophobic d-α-tocopherol succinate (TS) and a hydrophilic vancomycin (VCM) were formulated, and its potential for enhancing the antibacterial activity of VCM against Staphylococcus aureus (SA) and Methicillin-resistant Staphylococcus aureus (MRSA) were explored. The SADDs were synthesized via supramolecular complexation, then characterized for in silico, in vitro and in vivo studies. In silico studies confirmed the self-assembly of VCM/TS into NPs. The size, surface charge and drug loading of the SADDs was ˂100 nm, −27 mV and 68%, respectively. The SADDs were non-hemolytic and biosafe. A sustained release of VCM from SADDs was noted, with 52.2% release after 48 hr. The in vitro antibacterial test showed a twofold decrease in Minimum inhibitory concentration (MIC) against SA and MRSA, and a significantly higher reduction in MRSA biofilms compared to bare VCM. Further, in silico studies confirmed strong and stable binding of TS to MRSA efflux pumps. The in vivo study using mice skin infection models showed a 9.5-fold reduction in bacterial load after treatment with SADDs, in comparison with bare VCM. These findings affirmed that VCM/TS NPs as a promising novel nano-delivery for treating bacterial infections.

A bio-orthogonal functionalization strategy for site-specific coupling of antibodies on vesicle surfaces after self-assembly

Attaching targeting ligands on the surface of self-assembled drug delivery systems is one of the key requests for a controlled transport of the drug to a desired location.

The Benefits of Macromolecular/Supramolecular Approaches in Hydrogen Sulfide Delivery: A Review of Polymeric and Self-Assembled Hydrogen Sulfide Donors.

Significance: Cell homeostasis and redox balance are regulated in part by hydrogen sulfide (H2S), a gaseous signaling molecule known as a gasotransmitter. Given its biological roles, H2S has promising therapeutic potential, but controlled delivery of this reactive and hazardous gas is challenging due to its promiscuity, rapid diffusivity, and toxicity at high doses. Macromolecular and supramolecular drug delivery systems are vital for the effective delivery of many active pharmaceutical ingredients, and H2S stands to benefit greatly from the tunable physical, chemical, and pharmacokinetic properties of polymeric and/or self-assembled drug delivery systems. Recent Advances: Several types of H2S-releasing macro- and supramolecular materials have been developed in the past 5 years, and the field is expanding quickly. Slow-releasing polymers, polymer assemblies, polymer nano- and microparticles, and self-assembled hydrogels have enabled triggered, sustained, and/or localized H2S delivery, and many of these materials are more potent in biological assays than analogous small-molecule H2S donors. Critical Issues: H2S plays a role in a number of (patho)physiological processes, including redox balance, ion channel regulation, modulation of inducible nitric oxide synthase, angiogenesis, blood pressure regulation, and more. Chemical tools designed to (i) deliver H2S to study these processes, and (ii) exploit H2S signaling pathways for treatment of diseases require control over the timing, rate, duration, and location of release. Future Directions: Development of new material approaches for H2S delivery that enable long-term, triggered, localized, and/or targeted delivery of the gas will enable greater understanding of this vital signaling molecule and eventually expedite its clinical application.

Microfluidics for Cancer Nanomedicine: From Fabrication to Evaluation.

Self-assembled drug delivery systems (sDDSs), made from nanocarriers and drugs, are one of the major types of nanomedicines, many of which are in clinical use, under preclinical investigation, or in clinical trials. One of the hurdles of this type of nanomedicine in real applications is the inherent complexity of their fabrication processes, which generally lack precise control over the sDDS structures and the batch-to-batch reproducibility. Furthermore, the classic 2D in vitro cell model, monolayer cell culture, has been used to evaluate sDDSs. However, 2D cell culture cannot adequately replicate in vivo tissue-level structures and their highly complex dynamic 3D environments, nor can it simulate their functions. Thus, evaluations using 2D cell culture often cannot correctly correlate with sDDS behaviors and effects in humans. Microfluidic technology offers novel solutions to overcome these problems and facilitates studying the structure-performance relationships for sDDS developments. In this Review, recent advances in microfluidics for 1) fabrication of sDDSs with well-defined physicochemical properties, such as size, shape, rigidity, and drug-loading efficiency, and 2) fabrication of 3D-cell cultures as "tissue/organ-on-a-chip" platforms for evaluations of sDDS biological performance are in focus.

Self-assemblies of 5′-cholesteryl-ethyl-phosphoryl zidovudine

Anti-HIV prodrugs are recently focused on due to their ability of self-assembly, macrophage targeting, and enhanced antiviral effects. Here, an amphiphilic prodrug of zidovudine, an anti-HIV nucleoside analogue, 5′-cholesteryl-ethyl-phosphoryl zidovudine (CEPZ) was synthesized. CEPZ showed some unique physicochemical properties. The solubility of CEPZ in the noncompetitive solvents chloroform and tetrahydrofuran (THF) was very high based on the hydrogen bonds between zidovudine groups, though CEPZ was sparing soluble in alcohols and almost insoluble in water. The typical amphiphilic property of CEPZ was demonstrated according to the Langmuir monolayers at the air/water interface. The LogP of CEPZ was high to 13.78, indicating the high hydrophobicity of amphiphilic CEPZ similar to phospholipids. Homogenous and stable self-assemblies were formed with the mean size of 128.7nm and the zeta potential of −35.4mV after injecting the CEPZ-in-THF solution into water. Hydrophobic interaction between the cholesteryl moieties of CEPZ could drive molecular self-assembly and lead to the formation of spherical vesicles. CEPZ self-assemblies showed strong stability even under high temperature and gravity probably due to the high surface charge. CEPZ was very slowly degraded in neutral solutions (e.g., pH 7.4), but fast in acid solutions (e.g., pH 5.0) and some tissue homogenates. CEPZ was quickly eliminated from the circulation and distributed into the mononuclear phagocyte system (MPS) including the liver, spleen and lung after bolus intravenous administration of CEPZ self-assemblies to mice. The MPS targeting effect of CEPZ self-assemblies makes them become a promising self-assembled drug delivery system to eradicate the HIV hidden in the macrophages.

Self-assembled drug delivery system based on low-molecular-weight bis-amide organogelator: synthesis, properties and in vivo evaluation

Context: Orgnaogels based on amino acid derivatives have been widely used in the area of drug delivery.Objective: An organogel system based on l-lysine derivatives was designed and prepared to induce a thermal sensitive implant with higher transition temperature, better mechanical strength, and shorter gelation time.Materials and methods: The organogel was prepared by injectable soybean oil and methyl (S)-2,5-ditetradecanamidopentanoate (MDP), which was synthesized for the first time. Candesartan cilexetil (CC) was chosen as model drug. Different formulations were designed and optimized by response surface method. Thermal, rheology properties, and gelation kinetics of the optimized formulation had been characterized. The release behaviors in vitro, as well as in vivo were evaluated in comparison with the oily solution of drugs. Finally, the local inflammation response of in situ organogel was assessed by histological analysis.Results and discussion: Results showed that the synthesized gelator, MDP, had a good gelation ability and the organogels obtained via the self-assembly of gelators in vegetable oils exhibited great thermal and rheology properties, which guaranteed their state in body. In vivo pharmacokinetic demonstrated that the organogel formulation could extend the drug release and maintain a therapeutically effective plasma concentration at least 10 d. In addition, this implant showed acceptable moderate inflammation.Conclusion: The in situ forming l-lysine-derivative-based organogel could be a promising matrix for sustained drug delivery of the drugs with low solubility.

Long-circulating and liver-targeted nanoassemblies of cyclic phosphoryl N-dodecanoyl gemcitabine for the treatment of hepatocellular carcinoma.

Hepatocellular carcinoma (HCC) is a serious cancer with high mortality worldwide. Gemcitabine (GEM) is easily degraded in the circulation and has no tumor-targeted effect. In our previous research, an amphiphilic GEM derivative, cyclic phosphoryl N-dodecanoyl gemcitabine (CPDG) was prepared based on the techniques of HepDirect prodrug and self-assembled drug delivery systems (SADDS), which self-assembled into the stable nanoassemblies in water. In this study, the long-circulating nanoassemblies of CPDG/CHS-PEG1500 (9:1, mol/mol) were prepared for HCC treatment. In vitro and in vivo studies of the long-circulating CPDG nanoassemblies were explored. The degradation rates of CPDG depended on the media. CPDG showed much faster degradation in the acidic environment (pH 2.0) than the weak acidic and neutral media (pH 5.0, pH 7.4). However, the degradation half-life (t1/2) of CPDG was about 43h in the mouse plasma, longer than the t1/2 at pH 2.0. Therefore, the long-circulating CPDG nanoassemblies could keep stable before reaching the targets in vivo. In the biodistribution study, the long-circulating CPDG nanoassemblies were bolus intravenously (i.v.) injected into the hepatocellular tumor-bearing mice. The distribution of CPDG in the tumors was much higher than that in the blood, indicating the tumor targeting of the long-circulating nanoassemblies. In the pharmacodynamic study, the long-circulating CPDG nanoassemblies were i.v. injected into the tumor-bearing mice with doses of (37.5, 75 μmol/kg) compared with GEM (150 μmol/kg). The mice were injected once every 3 days for totally 3 times. The long-circulating nanoassemblies nearly always showed the higher anti-cancer effects than GEM. The tumor inhibitory rates of GEM, the long circulating CPDG nanoassemblies (37.5, 75 μmol/kg) were 49.54, 42.97, 65.10%, respectively. Therefore, the long-circulating CPDG nanoassemblies had the much higher anti-cancer effect than GEM. The long-circulating CPDG nanoassemblies are promising nanomedicines to treat HCC. The combination design of tumor-targeted nanoassemblies based on HepDirect prodrug technique and SADDS theory is an effective method to modify the pharmacologically active nucleosides to treat some liver diseases.

Self-assembled drug delivery systems: the art of prodrug, molecular self-assembly and nanotechnology

Self-assembled drug delivery systems: the art of prodrug, molecular self-assembly and nanotechnology

Biotinylated carboxymethyl chitosan/CaCO3 hybrid nanoparticles for targeted drug delivery to overcome tumor drug resistance

A tumor targeted nano-sized self-assembled drug delivery system could efficiently co-deliver an anti-cancer drug and a drug resistance inhibitor to tumor cells and achieve an improved therapeutic efficiency through inhibition of P-gp function.

Molecular self-assembly of amphiphilic cyclic phosphoryl gemcitabine with different N-fatty acyl tails and enhanced anticancer effects of the self-assembled nanostructures

Molecular self-assembly of nucleosides is important, and the self-assembled nanostructures may be used for drug delivery and targeting. Gemcitabine (GEM) is an important anticancer nucleoside analog though deactivation and multi-drug resistance frequently happen. Four N-fatty acyl derivatives of cyclic phosphoryl GEM were prepared based on the theory of self-assembled drug delivery systems and the HepDirect prodrug technique wherein the prodrug could be degraded by the cytochrome P450 isozymes in hepatocytes to release active drugs. They are cyclic phosphoryl N-octyl gemcitabine (CPOG), cyclic phosphoryl N-dodecanoyl gemcitabine (CPDG), cyclic phosphoryl N-hexadecanoyl gemcitabine (CPHG), and cyclic phosphoryl N-octadecanoyl gemcitabine (CPODG). Their amphiphilicity and self-assembling property were explored. The self-assembled nanostructures of them were prepared and simulated. The in vitro anticancer activities of the nanostructures were investigated. The derivatives formed the Langmuir monolayers at the air/water interface, though their surface pressure–molecular area isotherms were different with dependency of the length of lipid chains. The derivatives self-assembled into the vesicular or rice-like nanostructures based on the hydrophobic interaction between lipid chains when injected into water, in accordance with the results of computer simulation. The nanostructures showed higher anticancer effects on HepG2 cells than GEM. The nanostructures are promising anticancer nanomedicines.

PH-Driven Colloidal Transformations Based on the Vasoactive Drug Nicergoline

The structure of colloidal self-assembled drug delivery systems can be influenced by intermolecular interactions between drug and amphiphilic molecules, and is important to understand in the context of designing improved delivery systems. Controlling these structures can enable controlled or targeted release systems for poorly water-soluble drugs. Here we present the interaction of the hydrophobic vasoactive drug nicergoline with the internal structure of nanostructured emulsion particles based on the monoglyceride-water system. Addition of this drug leads to modification of the internal bicontinuous cubic structure to generate highly pH-responsive systems. The colloidal structures were characterized with small-angle X-ray scattering and visualized using cryogenic transmission electron microscopy. Reversible transformations to inverse micelles at high pH, vesicles at low pH, and the modification of the spacing of the bicontinuous cubic structure at intermediate pH were observed, and enabled the in situ determination of an apparent pKa for the drug in this system--a difficult task using solution-based approaches. The characterization of this phase behavior is also highly interesting for the design of pH-responsive controlled release systems for poorly water-soluble drug molecules.

Self-assembled drug delivery systems. Part 8: In vitro/in vivo studies of the nanoassemblies of cholesteryl-phosphonyl gemcitabine

A lipid derivative of gemcitabine (Gem), cholesteryl-phosphonyl gemcitabine (CPNG) was synthesized in this study. The amphiphilicity of CPNG was confirmed using a Langmuir monolayer method. Nanoassemblies were formed when the mixture of CPNG and a long-circulating material, CHS-PEG1500 (9:1, mol/mol) were injected into water. The nanoassemblies could be spherical vesicles according to the transmission electron microscopic images. Their mean size was 71.1nm and the zeta potential was −17.6mV. CPNG maintained stable in the weakly acidic and neutral environments although mouse plasma quickly degraded CPNG. The cytotoxicity of the nanoassemblies was 3–6 folds of Gem's cytotoxicity on five human cancer cell lines including 95C, 95D, A549, SW620, PANC-1 probably because of the phosphonyl substitution and amphiphilicity of CPNG. CPNG mainly distributed into the mononuclear macrophage system (including liver and spleen) after bolus intravenous administration of the nanoassemblies into mice though the expected significant long-circulating effect was not shown. The nanoassemblies with the high dose of CPNG showed the statistically higher in vivo anticancer effect than Gem. This study indicates that the N-substituted lipid derivative of Gem and the true long-circulating function are necessary for preparing a successful nanoassembly of Gem.

Self-assembled drug delivery systems. Part 7: Hepatocyte-targeted nanoassemblies of an adefovir lipid derivative with cytochrome P450-triggered drug release

A novel strategy was used in the design of self-assembled drug delivery systems (SADDSs) in this study. The nanoassemblies of an amphiphilic adefovir lipid derivative were prepared and demonstrated to have the functions of hepatocyte targeting, enzyme-triggered drug release and high anti-hepatitis effect. An amphiphilic adefovir lipid derivative, N-lauroyl-1-(3-chlorophenyl)-1,3-propanyl phosphonyl adefovir (LCPA) was prepared and formed the nanoassemblies by injecting the mixture of LCPA and another amphiphilic polymer, d-galactide polyoxyethylene (20) cetyl ether (GPCE) (ca. 20:1, mol/mol) into water. The nanoassemblies were very stable and showed negative charge. LCPA was sensitive to the cytochrome P450 isozymes that were expressed predominantly in the hepatocytes to produce adefovir. GPCE contained a long hydrophilic chain and a galactose ligand targeting the asialoglycoprotein receptors overexpressed on the surface of hepatocytes. The nanoassemblies showed the long-circulating and liver targeting effects according to the results of pharmacokinetics, tissue distribution and fluorescence imagination after bolus intravenous administration of the nanoassemblies to the mice. The highly efficient hepatitis B treatment was achieved by 10 day continuous administration of the nanoassemblies to the HBV-infected mice. Many functions were combined in the nanoassemblies, including prodrug, molecular self-assembly, nanotechnology, long-circulating, hepatocyte targeting and hepatocyte over expressing enzyme-triggered drug release.