This study aims to prepare vitexin albumin nanoparticles(VT-BSA-NPs) to alleviate the low bioavailability of vitexin(VT) in vivo due to its poor water solubility. VT micro powders were prepared by the antisolvent crystallization method, and the morphology, size, and physicochemical properties of VT micro powders were studied. The results showed that the VT micro powder had a particle size of(187.13±7.15) nm, an approximate spherical morphology, and a uniform size distribution. Compared with VT, the chemical structure of VT micro powders has not changed. VT-BSA-NPs were prepared from VT micro powders by desolvation-crosslinking curing method. The preparation process was screened by single factor test and orthogonal test, and the quality evaluation of the optimal prescription particle size, PDI, Zeta potential, EE, and morphology was performed. The results showed that the average particle size of VT-BSA-NPs was(124.33±0.47) nm; the PDI was 0.184±0.012; the Zeta potential was(-48.83±2.20) mV, and the encapsulation rate was 83.43%±0.39%, all of which met the formulation-related requirements. The morphological results showed that the VT-BSA-NPs were approximately spherical in appearance, regular in shape, and without adhesion on the surface. In vitro release results showed a significantly reduced release rate of VT-BSA-NPs compared with VT, indicating a good sustained release effect. LC-MS/MS was used to establish an analytical method for in vivo analysis of VT and study the plasma pharmacokinetics of VT-BSA-NPs in rats. The results showed that the specificity of the analytical method was good, and the extraction recovery was more than 90%. Compared with VT and VT micro powders, VT-BSA-NPs could significantly increase AUC, MRT, and t_(1/2), which was beneficial to improve the bioavailability of VT.
Rats ; Animals ; Serum Albumin, Bovine/chemistry* ; Chromatography, Liquid ; Tandem Mass Spectrometry ; Nanoparticles/chemistry* ; Particle Size ; Drug Carriers/chemistry*

The application of intraocular drug delivery is usually limited due to special anatomical and physiological barriers, and the elimination mechanisms in the eye. Organic nano-drug delivery carriers exhibit excellent adhesion, permeability, targeted modification and controlled release abilities to overcome the obstacles and improve the efficiency of drug delivery and bioavailability. Solid lipid nanoparticles can entrap the active components in the lipid structure to improve the stability of drugs and reduce the production cost. Liposomes can transport hydrophobic or hydrophilic molecules, including small molecules, proteins and nucleic acids. Compared with linear macromolecules, dendrimers have a regular structure and well-defined molecular mass and size, which can precisely control the molecular shape and functional groups. Degradable polymer materials endow nano-delivery systems a variety of size, potential, morphology and other characteristics, which enable controlled release of drugs and are easy to modify with a variety of ligands and functional molecules. Organic biomimetic nanocarriers are highly optimized through evolution of natural particles, showing better biocompatibility and lower toxicity. In this article, we summarize the advantages of organic nanocarriers in overcoming multiple barriers and improving the bioavailability of drugs, and highlight the latest research progresses on the application of organic nanocarriers for treatment of ocular diseases.
Drug Carriers ; Delayed-Action Preparations ; Drug Delivery Systems ; Nanoparticles/chemistry*

Nucleoside drugs play an essential role in treating major diseases such as tumor and viral infections, and have been widely applied in clinics. However, the effectiveness and application of nucleoside drugs are significantly limited by their intrinsic properties such as low bioavailability, lack of targeting ability, and inability to enter the cells. Nanocarriers can improve the physiological properties of nucleoside drugs by improving drug delivery efficiency and availability, maintaining drug efficacy and system stability, adjusting the binding ability of the carrier and drug molecules, as well as modifying specific molecules to achieve active targeting. Starting from the design strategy of nucleoside drug nanodelivery systems, the design and therapeutic effect of these nanomedicines are described in this review, and the future development directions of nucleoside/nucleotide-loaded nanomedicines are also discussed.
Nanomedicine ; Nucleosides/chemistry* ; Nucleotides ; Nanoparticles/chemistry* ; Drug Delivery Systems ; Drug Carriers

Currently, the first-line drugs for invasive fungal infections (IFI), such as amphotericin B, fluconazole and itraconazole, have drawbacks including poor water solubility, low bioavailability, and severe side effects. Using drug delivery systems is a promising strategy to improve the efficacy and safety of traditional antifungal therapy. Synthetic and biomimetic carriers have greatly facilitated the development of targeted delivery systems for antifungal drugs. Synthetic carrier drug delivery systems, such as liposomes, nanoparticles, polymer micelles, and microspheres, can improve the physicochemical properties of antifungal drugs, prolong their circulation time, enhance targeting capabilities, and reduce toxic side effects. Cell membrane biomimetic drug delivery systems, such as macrophage or red blood cell membrane-coated drug delivery systems, retain the membrane structure of somatic cells and confer various biological functions and specific targeting abilities to the loaded antifungal drugs, exhibiting better biocompatibility and lower toxicity. This article reviews the development of antifungal drug delivery systems and their application in the treatment of IFI, and also discusses the prospects of novel biomimetic carriers in antifungal drug delivery.
Antifungal Agents/therapeutic use* ; Drug Delivery Systems ; Amphotericin B/therapeutic use* ; Liposomes/chemistry* ; Nanoparticles ; Drug Carriers

Vesicles derived from Chinese medicinal herbs (VCMH) are nano-vesicular entities released by the cells of Chinese medicinal herbs. VCMHs have various biological effects and targeting characteristics, and their component chemicals and functional activities are closely related to the parent plant. VCMH differs from animal-derived vesicles in three ways: stability, specificity, and safety. There are a number of extraction and isolation techniques for VCMH, each with their own benefits and drawbacks, and there is no unified standard. When two or more approaches are used, high quantities of intact vesicles can be obtained more quickly and efficiently. The obtained VCMHs were systematically examined and evaluated. Firstly, they are generally saucer-shaped, cup-shaped or sphere, with particle size of 10-300 nm. Secondly, they contain lipids, proteins, nucleic acids and other active substances, and these components are an important part for intercellular information transfer. Finally, they mostly have good biocompatibility and low toxicity, with anti-inflammatory, antioxidant, anti-tumor and anti-fibrotic effects. As a new drug carrier, VCMHs have outstanding active targeting capabilities, and the capsule form can effectively preserve the drugs, considerably enhancing drug delivery efficiency and stability in vitro and in vivo. The modification of its vesicular structure by suitable physical or chemical means can further create more stable and precise drug carriers. This article reviews the extraction and purification techniques, activity evaluation and application of VCMH to provide information for further research and application of new active substances and targeted drug carriers.
Animals ; Drugs, Chinese Herbal/chemistry* ; Plants, Medicinal ; Antioxidants ; Anti-Inflammatory Agents ; Drug Carriers

Objective:To prepare PLGA nanoparticles loaded with Der f 1/IGF-1（Der f 1/IGF-1 NPs） and investigate their role in promoting the formation of Treg cells. Methods:NPs coated with Der f 1/IGF-1 were prepared by double emulsion method and their physicochemical properties and cumulative release rate in vitro were analyzed. After pretreatment, BMDC was divided into Saline group, Blank NPs group, Der f 1/IGF-1 group and Der f 1/IGF-1 NPs group. Determination of the expression of IL-10 and TGF-β in BMDC by ELISA. The number of Treg cells was detected by flow cytometry. Results:The results showed that Der f 1/IGF-1 NPs were spherical structures, with good dispersion, particle size less than 200 nm, negative charge and stable slow-release effect of Zeta potential. After BMDC pretreatment, the expression levels of TGF-β and IL-10 in BMDC cells in the Der f 1/IGF-1 NPs group were significantly increased compared with the Blank NPs group, and the difference was statistically significant（P<0.001）. After co-culture with CD4+ T cells, the proportion of Treg cells produced in the Der f 1/IGF-1 NPs group was significantly increased, and the difference was statistically significant（P<0.001）. Conclusion:Der f 1/IGF-1 NPs can induce Treg cell generation in vitro. This study provides a new and more effective method for the reconstruction of immune tolerance dysfunction.
Humans ; T-Lymphocytes, Regulatory/metabolism* ; Interleukin-10/metabolism* ; Insulin-Like Growth Factor I ; Transforming Growth Factor beta ; Nanoparticles/chemistry* ; Particle Size ; Drug Carriers/chemistry*

Polymer micelles formed by self-assembly of amphiphilic polymers are widely used in drug delivery, gene delivery and biosensors, due to their special hydrophobic core/hydrophilic shell structure and nanoscale. However, the structural stability of polymer micelles can be affected strongly by environmental factors, such as temperature, pH, shear force in the blood and interaction with non-target cells, leading to degradations and drug leakage as drug carriers. Therefore, researches on the structural integrity and in vivo distribution of micelle-based carriers are very important for evaluating their therapeutic effect and clinical feasibility. At present, fluorescence resonance energy transfer (FRET) technology has been widely used in real-time monitoring of aggregation, dissociation and distribution of polymer micelles ( in vitro and in vivo). In this review, the polymer micelles, characteristics of FRET technology, structure and properties of the FRET-polymer micelles are briefly introduced. Then, methods and mechanism for combinations of several commonly used fluorescent probes into polymer micelles structures, and progresses on the stability and distribution studies of FRET-polymer micelles ( in vitro and in vivo) as drug carriers are reviewed, and current challenges of FRET technology and future directions are discussed.
Micelles ; Drug Carriers/chemistry* ; Polymers/chemistry* ; Fluorescence Resonance Energy Transfer ; Polyethylene Glycols/chemistry*

Hesperetin, an abundant bioactive component of citrus fruits, is poorly water-soluble, resulting in low oral bioavailability. We developed new formulations to improve the water solubility, antioxidant activity, and oral absorption of hesperetin. Two nano-based formulations were developed, namely hesperetin-TPGS (D-α-tocopheryl polyethylene glycol 1000 succinate) micelles and hesperetin-phosphatidylcholine (PC) complexes. These two formulations were prepared by a simple technique called solvent dispersion, using US Food and Drug Administration (FDA)-approved excipients for drugs. Differential scanning calorimetry (DSC) and dynamic light scattering (DLS) were used to characterize the formulations' physical properties. Cytotoxicity analysis, cellular antioxidant activity assay, and a pharmacokinetic study were performed to evaluate the biological properties of these two formulations. The final weight ratios of both hesperetin to TPGS and hesperetin to PC were 1:12 based on their water solubility, which increased to 21.5- and 20.7-fold, respectively. The hesperetin-TPGS micelles had a small particle size of 26.19 nm, whereas the hesperetin-PC complexes exhibited a larger particle size of 219.15 nm. In addition, the cellular antioxidant activity assay indicated that both hesperetin-TPGS micelles and hesperetin-PC complexes increased the antioxidant activity of hesperetin to 4.2- and 3.9-fold, respectively. Importantly, the in vivo oral absorption study on rats indicated that the micelles and complexes significantly increased the peak plasma concentration (C_max) from 2.64 μg/mL to 20.67 and 33.09 μg/mL and also increased the area under the concentration-time curve of hesperetin after oral administration to 16.2- and 18.0-fold, respectively. The micelles and complexes increased the solubility and remarkably improved the in vitro antioxidant activity and in vivo oral absorption of hesperetin, indicating these formulations' potential applications in drugs and healthcare products.
Administration, Oral ; Animals ; Antioxidants/chemistry* ; Biological Availability ; Calorimetry, Differential Scanning ; Dogs ; Dose-Response Relationship, Drug ; Drug Carriers ; Female ; Hep G2 Cells ; Hesperidin/chemistry* ; Humans ; Light ; Madin Darby Canine Kidney Cells ; Micelles ; Phosphatidylcholines/chemistry* ; Polyethylene Glycols/chemistry* ; Rats ; Rats, Sprague-Dawley ; Scattering, Radiation ; Solubility ; Solvents ; Vitamin E/chemistry* ; Water/chemistry* ; alpha-Tocopherol/chemistry*

BackgroundPaclitaxel (PTX) could inhibit the growth of fibroblasts, which occurs in proliferative cholangitis and leads to biliary stricture. However, its use has been limited due to poor bioavailability and local administration for short time. This study designed and synthesized a new PTX-conjugated chitosan film (N-succinyl-hydroxyethyl chitosan containing PTX [PTX-SHEC]) and evaluated its safety and efficiency using in vivo and in vitro experiments.

Methods:The SHEC conjugated with PTX was confirmed by nuclear magnetic resonance (NMR) and Fourier-transform infrared spectroscopy (FT-IR) measurements. Drug releases in vitro and in vivo were determined using high-performance liquid chromatography. Cell viability in vitro was measured using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide. Rabbit biliary stricture model was constructed. All rabbits randomly divided into five groups (n = 8 in each group): the sham-operated rabbits were used as control (Group A), Groups B received laparotomies and suture, Group C received laparotomies and covered SHEC suture without the PTX coating, Group D received laparotomies and covered PTX-SHEC suture, and Group E received laparotomies and 1000 μmol/L PTX administration. Liver function tests and residual dosage of PTX from each group were measured by enzyme-linked immunosorbent assay. Histological data and α-smooth muscle actin (SMA) immunohistochemical staining of common bile duct were examined.

Results:NMR and FT-IR indicated that PTX was successfully introduced, based on the appearance of signals at 7.41-7.99 ppm, 1.50 ppm, and 1.03 ppm, due to the presence of aromatic protons, methylene protons, and methyl protons of PTX, respectively. No bile leak was observed. The PTX-conjugated film could slowly release PTX for 4 weeks (8.89 ± 0.03 μg at day 30). The in vitro cell viability test revealed significantly different levels of toxicity between films with and without PTX (111.7 ± 4.0% vs. 68.1 ± 6.0%, P < 0.001), whereas no statistically significant difference was observed among the three sets of PTX-contained films (67.7 ± 5.4%, 67.2 ± 3.4%, and 59.1 ± 6.0%, P > 0.05). Histological examinations revealed that after 28 days of implantment, Groups D and E (but not Group C) had less granulation tissue and glandular hyperplasia in the site of biliary duct injury than Group B. The pattern was more obvious in Group D than Group E. Less α-SMA-positive cells were found in tissue from Groups D and E. Comparing with Group E, the liver function was improved significantly in Group D, including total bilirubin (2.69 ± 1.03 μmol/L vs. 0.81 ± 0.54 μmol/L, P = 0.014), alanine aminotransferase (87.13 ± 17.51 U/L vs. 42.12 ± 15.76 U/L, P = 0.012), and alkaline phosphatase (60.61 ± 12.31 U/L vs. 40.59 ± 8.78 U/L, P < 0.001).

ConclusionsPTX-SHEC film effectively inhibites the myofibroblast proliferation and extracellular matrix over-deposition during the healing process of biliary reconstruction. This original film might offer a new way for reducing the occurrence of the benign biliary stricture.

Animals ; Cell Line, Tumor ; Cell Proliferation ; drug effects ; Chitosan ; chemistry ; Cholangitis ; drug therapy ; Drug Carriers ; chemistry ; Humans ; Magnetic Resonance Spectroscopy ; Membranes, Artificial ; Paclitaxel ; chemistry ; pharmacology ; therapeutic use ; Rabbits ; Spectroscopy, Fourier Transform Infrared

The therapeutic application of deoxypodophyllotoxin (DPT) is limited due to its poor water solubility and stability. In the present study, the micelles assembled by the amphiphilic block copolymers (mPEG-PDLLA) were constructed to improve the solubility and safety of DPT for their in vitro and in vivo application. The central composite design was utilized to develop the optimal formulation composed of 1221.41 mg mPEG-PDLLA, the weight ratio of 1 : 4 (mPEG-PDLLA : DPT), 30 mL hydration volume and the hydration temperature at 40 °C. The results showed that the micelles exhibited uniformly spherical shape with the diameter of 20 nm. The drug-loading and entrapment efficiency of deoxypodophyllotoxin-polymeric micelles (DPT-PM) were about (20 ± 2.84)% and (98 ± 0.79)%, respectively, indicating that the mathematical models predicted well for the results. Compared to the free DPT, the cytotoxicity showed that blank micelles possessed great safety for Hela cells. In addition, the DPT loaded micelle formulation achieved stronger cytotoxicity at the concentration of 1 × 10 mol·L, which showed significant difference from free DPT (P < 0.05). In conclusion, the micelles were highly promising nano-carriers for the anti-tumor therapy with DPT.
Antineoplastic Agents ; chemistry ; toxicity ; Cell Survival ; drug effects ; Drug Carriers ; chemistry ; Drug Delivery Systems ; methods ; Drug Design ; HeLa Cells ; Humans ; Micelles ; Particle Size ; Podophyllotoxin ; analogs & derivatives ; chemistry ; toxicity ; Polyesters ; chemistry ; Polyethylene Glycols ; chemistry ; Solubility ; Surface Properties