It is crucial to develop non-viral gene vectors that can efficiently and safely transfect plasmid DNA into cells. Low transfection efficiency and high cytotoxicity of cationic polymers hinder their application as gene carriers. Modification of cationic polymers has emerged as an attractive strategy for efficient and safe nucleic acids delivery. In this study, a simple and rapid method is developed to synthesize a series of multifunctional polymers by utilizing biodegradable polyaspartic acid as the backbone and modifying it with three modules. This one-component polymer possesses capabilities for nucleic acid condensation, cellular uptake, and endosomal escape. Polymers containing imidazole, triazole, or pyridine group exhibited promising transfection activity. Substituted with dodecylamine or 2-hexyldecan-1-amine enhance cellular uptake and subsequent transfection. Furthermore, the influence of ionizable amine side chains on gene delivery is investigated. Two optimal polymers, combined with the avian encephalomyelitis virus (AEV) plasmid vaccine, induced robust specific antibody responses and cellular immune responses in mice and chickens. Through module-combination design and screening of polyaspartamide polymers, this study presents a paradigm for the development of gene delivery vectors.
Objective:To develop an etonogestrel (ENG)/ethinyl estradiol (EE) compound vaginal ring with good sustained-release properties, studying its in vitro release assay methodology, and establishing an accelerated release method with good correlation with real-time release methods. Methods:Ethylene-vinyl acetate copolymer (EVA) was used as the matrix to prepare ENG/EE compound vaginal ring by hot melt extrusion method, and an in vitro real-time release assay method and an accelerated release assay method based on shake flask method were established. The in vitro release behavior and release mechanism of ENG/EE compound vaginal ring were investigated, and the correlation between real-time release and accelerated release over time was analyzed. Results:The obtained vaginal ring had a round appearance and a smooth surface, and the drug was slowly released under the optimal real-time release conditions in vitro (release medium: 200 mL of pure water, shaking at 60 r/min in a constant temperature water bath shaker at 37 ℃), and the cumulative release of ENG and EE on the 21st day were 54.39% and 46.80%, respectively. The correlation coefficients of drug release and its mechanism under the optimized in vitro accelerated conditions (release medium: 200 mL of 0.6% sodium dodecyl sulfate aqueous solution, shaking at 60 r/min at 55 ℃) with the results under real-time release conditions were all greater than 0.99. Conclusion:The ENG/EE compound vaginal ring obtained in this study has a significant in vitro sustained-release effect, and the established accelerated release conditions have a good correlation with real-time release conditions, which can provide a useful reference for the quality evaluation research of such vaginal ring products and the formulation of guidelines for in vitro release research methods.
Background: Subcutaneous injection of biopharmaceutical agents or microparticles is challenging due to issues with low injection efficiency and high residual amounts. Objective: This study aimed to determine the important factors affecting the injectability of microparticle delivery systems, establish a suitable injection system with lower injection force and higher discharge rate, and eventually develop a reliable injectability evaluation system for injectable microparticle delivery systems in vitro andin vivo. Methods: The effects of various parameters, including particle size, injection speed, concentration of microspheres suspension, vehicle viscosity, needle length and gauge were evaluated by measuring the injection force and discharge rate. The characteristics of microparticles and rheological measurement of the suspension systems were studied. A design of experiment approach was utilized to evaluate the interaction between the microsphere suspension, vehicle viscosity and needle gauges. Both in vitro sieve tests andin vivo tests in rats were conducted to evaluate injectability. Results: The in vitro test results showed that the vehicle viscosity and injection speed have varying effects on discharge rate and injection force, respectively. Particle size and needle gauge have substantial influence on injectability, larger particle size and smaller needle gauges resulting in poor injectability, while the needle gauge was found to have the greatest influence on injectability. Levonorgestrel (LNG) microsphere and glass bead were relatively uniform spherical, the glass bead had extremely smooth surface; while mesoporous silica had irregular shape. The settling rate of glass bead was the fastest, which was about 18 times faster than the LNG microsphere. The CMC-Na had a poor interaction with the LNG microspheres, glass bead and mesoporous silica and showed basically Newtonian behavior in the shear rate range of 0.1 s- 1-100 s-1. When shear rate increased to more than 100 s-1, no obvious shear thinning behavior was observed. CMC-Na formed a nodule structure with whether LNG microspheres or the glass beads, which were much lower than that with the mesoporous silica in static state, among which the glass beads were the weakest. The viscosity of the suspension increased with the rising of the volume fraction of particles. Fundamentals of hydrodynamics in capillaries were referenced, such as Navier-Stokes Law equation, Krieger-Dougherty (K-D) equation, Hagen-Poiseuille equation. The best results achieved was using a suspension concentration of 120-240 mg /mL and a viscosity of 60 cP at 20 degrees C with 23-gauge needles. The optimized conditions were verified in vivo tests. It was proven that the LNG microsphere suspen-sion had a good injectability when injected into subcutaneous tissue of rats. Conclusion: The injection system of injectable microparticle delivery system with lower injection force and higher discharge rate was established and the evaluation method was suitable for the injectability evaluation both in vivo and in vitro. Improved injectability would promote the clinical translation of microparticle delivery systems.
The adjuvant is essential for vaccines because it can enhance or directly induce a strong immune response associated with vaccine antigens. Ginsenoside Rh2 (Rh2) had immunomodulatory effects but was limited by poor solubility and hemolysis. In this study, Rh2 liposomes (Rh2-L) were prepared by ethanol injection methods. The Rh2-L effectively dispersed in a double emulsion adjuvant system to form a Water-in-Oil-in-Water (W/O/W) emulsion and had no hemolysis. The physicochemical properties of the adjuvants were tested, and the immune activity and auxiliary effects indicated by the Foot-and-Mouth disease (FMDV) antigen were evaluated. Compared with the mice vaccinated with the FMD vaccine prepared with the double emulsion adjuvant alone, those with the FMD vaccine prepared with the double emulsion adjuvant containing Rh2-L had significantly higher neutralizing antibody titer and splenocyte proliferation rates and showed higher cellular and humoral immune responses. The results demonstrated that Rh2-L could further enhance the immune effect of the double emulsion adjuvant against Foot-and-Mouth Disease.
Cholesterol (CHOL) is essential for developing lipid nanoparticles (LNPs) for gene delivery because it enhances membrane fusion and improves the delivery efficiency of gene cargos. An attractive pDNA carrier, corosolic acid (CA)-modified lipid nanoparticles (CLNPs), was developed by replacing CHOL in LNPs to deliver pDNA at various ratios of nitrogen groups to phosphate groups (N/P). The resultant CLNPs with a higher CHOL/CA ratio exhibited similar mean particle size, zeta potential, and encapsulation efficiency to those of LNPs. In comparison with LNPs, CLNPs (CHOL:CA ratio = 2:1) achieved increased cellular uptake and enhanced transfection efficacy while maintaining low cytotoxicity. In vivo results from chicken experiments demonstrated that CLNPs encapsulating DNA vaccines against avian influenza at a N/P ratio of 3 could elicit similar-level humoral and cellular immune responses compared with those of LNPs at a higher N/P ratio, thereby suggesting the induction of desirable immune effects using less ionizable lipids. Our study provides a reference for further research on the application of CA in LNPs for gene delivery, and the development of novel delivery systems for DNA vaccines against avian influenza.
Microparticles (MPs) and amorphous solid dispersions (SDs) are effective methods to improve the dissolution of insoluble drugs. However, stability is a concern for these two high-energy systems, resulting from high surface area and amorphous polymorph, respectively. As an amphiphilic polymer, Soluplus (SOL) is usually used as a carrier in SDs. In this study, erlotinib microparticles (ERL MPs) and erlotinib solid dispersions (ERL SDs) were prepared with SOL by bottom-up technology and solvent evaporation. The solid-state properties of ERL MPs and ERL SDs were characterized by Differential Scanning Calorimetry (DSC), Powder X-Ray Diffraction (PXRD) and Scanning Electron Microscopy (SEM). The ERL MPs existed in a metastable crystal form A while the ERL SDs existed in an amorphous state. Fourier transform infrared spectroscopy (FT-IR) showed that there was a hydrogen bond interaction between the N-H group of ERL and the carbonyl group of SOL in ERL MPs and SDs. The dissolution profiles of ERL SDs and ERL MPs were improved significantly. ERL MPs showed better stability than ERL SDs in accelerated stability test. The discrepant stabilizing effects of polymer SOL in two systems may provide effective ideas for solubilization of insoluble drugs and the stability of drugs after recrystallization.
目的 制备并表征达那唑(DAZ)-酪蛋白酸钠(SC)复合纳米粒,探讨"自下而上(bottom-up)"工艺中纳米粒形成的机制.方法 以SC作为调控纳米粒的稳定剂,通过反溶剂沉淀法制备DAZ-SC复合纳米粒,对其粒径、Zeta电位、微观形态、稳定性、包封率、载药量、体外溶出度等进行表征,进一步利用荧光光谱、红外光谱和在线粒子监测等方法分析DAZ与SC的相互作用机制.结果 DAZ-SC复合纳米粒的粒径为(223.7±12.5)nm,多分散性指数为0.274±0.012,Zeta电位为-(17.81±1.63)mV(n=3);纳米混悬液的稳定性良好,DAZ的固态性质明显改善,溶出度显著提高.SC在DAZ的作用下发生静态淬灭,二级结构有所改变;在SC的作用下,DAZ的结晶过程得到控制;DAZ与SC之间的相互作用主要为氢键和范德华力.结论 本研究成功制备了DAZ-SC复合纳米粒;在"bottom-up"工艺中,因SC与DAZ之间氢键和范德华力引起的相互作用抑制了药物晶体的生长与团聚.
研究微流控聚焦装置液滴生成特性是液滴微流控芯片结构优化设计的基础.利用水平集方法结合有限元技术建立了微流控聚焦装置内液滴生成过程的数值计算模型,并分析了分散相与连续相流速比、微流道几何结构对液滴生成机制和液滴生成特性的影响规律.在一定的流速比、微流道入口宽度比范围内,均生成了性态良好的液滴.当分散相与连续相入口宽度比大于1时,液滴尺寸随连续相入口宽度、连续相流速的增大而减小,液滴生成频率随连续相入口宽度、连续相流速的增大而增大;当分散相与连续相入口宽度比小于1时,液滴尺寸随分散相入口宽度增大而增大,随连续相流速的增大而减小,液滴生成频率随分散相入口宽度、连续相流速的增大而增大.数值计算结果表明:微流控聚焦装置液滴生成受几何结构、流速及两相流体物性参数的耦合作用,模拟计算的结果可为微流控聚焦装置结构优化设计提供指导.
Cannabidiol (CBD), a primary bioactive phytocannabinoid extracted from hemp, is reported to possess potent anti-tumorigenic activity in multiple cancers. However, the effects of CBD on bladder cancer (BC) and the underlying molecular mechanisms are rarely reported. Here, several experiments proved that CBD promoted BC cells (T24, 5637, and UM-UC-3) death. For example, T24 cells were treated with 12 µM CBD for 48 h, flow cytometry analysis demonstrated that early and late apoptotic cells were accounted for by 49.91%, indicating CBD enhanced cell apoptosis ability. To deeper explore molecular mechanisms, the CBD-treated T24 cell transcriptome libraries were established. KEGG analysis implied that the significantly changed genes were enriched in the PI3K/Akt pathway. qRT-PCR and Western blot assays verified that CBD regulated BC cells growth and migration and induced apoptosis by inactivating the PI3K/Akt pathway. Meanwhile, the developed chitosan to wrap CBD-loaded PLGA nanoparticles can significantly enhance the adhesion of the material to the mouse bladder wall, and the binding efficiency of mucin to chitosan-PLGA nanoparticles reached 97.04% ± 1.90%. In summary, this work demonstrates that CBD may become a novel reliable anticancer drug and the developed intravesical adhesion system is expected to turn into a potential means of BC chemotherapy drug delivery.
Biodegradable poly(lactic-co-glycolic acid) nanoparticles (PLGA NPs) have been widely used as delivery vehicles for chemotherapy drugs. However, premature drug release in PLGA NPs can damage healthy tissue and cause serious adverse effects during systemic administration. Here, we report a tannic acid-Fe(III) (FeIII-TA) complex-modified PLGA nanoparticle platform (DOX-TPLGA NPs) for the tumor-targeted delivery of doxorubicin (DOX). A PEGylated-PLGA inner core and FeIII-TA complex outer shell were simultaneously introduced to reduce premature drug release in blood circulation and increase pH-triggered drug release in tumor tissue. Compared to the unmodified NPs, the initial burst rate of DOX-TPLGA NPs was significantly reduced by nearly 2-fold at pH 7.4. Moreover, the cumulative drug release rate at pH 5.0 was 40% greater than that at pH 7.4 due to the pH-response of the FeIII-TA complex. Cellular studies revealed that the TPLGA NPs had enhanced drug uptake and superior cytotoxicity of breast cancer cells in comparison to free DOX. Additionally, the DOX-TPLGA NPs efficiently accumulated in the tumor site of 4T1-bearing nude mice due to the enhanced permeability and retention (EPR) effect and reached a tumor inhibition rate of 85.53 ± 8.77% (1.31-fold versus DOX-PLGA NPs and 3.12-fold versus free DOX). Consequently, the novel TPLGA NPs represent a promising delivery platform to enhance the safety and efficacy of chemotherapy drugs.
将思想政治教育内容融入专业课程是深化高等教育改革的重要改革目标.从药品生产质量管理课程的思政教学目标、思政教学内容和教学方法等方面论述具体的改革思路与方法.
Multi-cell coupled droplet generator systems have been used for high-throughput production of microdroplets. However, the coupling effects of intercellular geometry and flow parameters can produce complex hydrodynamic phenomena that affect droplet generation processes and properties. In this study, a computational model of droplet generation in a multi-cell parallel geometry was developed based on the phase field method, and the droplet formation process and hydrodynamic properties in a multi-cell coupled droplet generator were investigated. The coupling effects of flow parameters (e.g., capillary number, continuous and dispersed phase flow rates and flow ratios) on the droplet generation process were systematically analyzed to investigate droplet characteristics and mechanisms in the multi-cell coupled droplet generator system. The causes of synchronous and asynchronous droplet generation patterns in multi-cell coupled systems are also analyzed over a range of capillary numbers. It is found that the droplet generation frequency increases with increasing continuous-phase flow velocity while the size decreases; the droplet size is smaller and the frequency is larger in multi-cell coupled systems than in stand-alone systems at the same flow velocity ratio; the difference between synchronous and asynchronous droplet generation patterns is closely related to the geometric coupling of continuous-phase flow channels and the uneven flow field distribution. This work will provide useful insights into droplet generation in multi-cell coupled systems and provide useful guidance for the structural design of multi-cell coupled systems.
Renal cell carcinoma (RCC) is a common malignant tumor of the urinary system with poor prognosis. Therapeutic drugs for RCC can easily develop resistance or have unignorable toxicity or limited efficiency. Here, the thermosensitive mitochondrial metabolism-interfering anticancer drug lonidamine (LND) was combined with the photothermal material polydopamine (PDA) to treat RCC. To delivery drugs accurately to RCC site, LND and PDA were loaded in stellate mesoporous silica nanoparticles (MSNs) with a large surface area and cloaked with RCC membranes (MLP@M). The results showed that MLP@M exhibited excellent tumor targeting ability. The synergistic effects of LND and PDA in MLP@M were greatly enhanced when triggered by an 808 nm laser. Moreover, the antiproliferative and tumor suppressing abilities were enhanced with good biocompatibility after MLP@M + laser treatment. Additionally, 80% of RCC tumor-bearing mice treated with MLP@M + laser did not relapse. Our study provides a potential therapeutic approach for RCC treatment.
As a classic drug with several hydrate forms, Calcium Dobesilate is widely used in the treatment of diabetic retinopathy and chronic venous insufficiency, and Monohydrate is the medicinal form. The key impurity, hydroquinone, is an important synthetic raw material of Calcium Dobesilate, but has a potential genotoxicity, so the content of hydroquinone in the final product should be lower. In this paper, based on characterization results of different hydrates, the Dihydrate is found as the beneficial form for purification, thus a novel crystallization process for purification has been carried out. The Dihydrate is obtained by a recrystallization and then transformed into the Monohydrate. From the results of solid-state characterization and process analysis of phase transformation, the transformation relationship between the two hydrates is determined, and it is found out that the transformation from Dihydrate to Monohydrate could only happen via solution-mediated transformation in Ethanol or Isopropanol. The impurity content of the Monohydrate product prepared by the new crystallization process is far below the current standard in the Pharmacopoeia.
PURPOSE:Nimodipine (NIMO) is used clinically to treat ischemic damage resulting from subarachnoid hemorrhage. However, clinical application of NIMO is limited by poor aqueous solubility and low safety. To overcome these limitations, a novel two-vial NIMO-loaded nanoemulsion (NIMO-TNE) was designed in this study.METHODS:NIMO-TNE was prepared by mixing a nimodipine-polyethylene glycol 400 (NIMO-PEG400) solution and a commercially available 20% injectable blank nanoemulsion (BNE). Drug distribution in NIMO-TNE, physical stability, and dilution stability were evaluated in vitro, and pharmacokinetics and pharmacodynamics were evaluated in vivo. Safety was assessed using the hemolysis test and the intravenous irritation test, and acute toxicity of NIMO-TNE was compared with that of commercial Nimotop injection.RESULTS:Drug loading (DL) in NIMO-TNE was enhanced 5-fold compared with that in Nimotop injection. The mean particle size of NIMO-TNE was 241.53 ± 1.48 nm. NIMO-TNE and NIMO-TNE diluted in 5% glucose injection and 0.9% sodium chloride was stable for a sufficient duration to allow for clinical use. In addition, NIMO-TNE exhibited a similar pharmacokinetic profile and similar brain ischemia reduction in a rat middle cerebral artery occlusion (MCAO) model compared to Nimotop injection. Furthermore, NIMO-TNE did not induce hemolysis at 37°C, and NIMO-TNE induced less intravenous irritation than Nimotop injection. Moreover, NIMO-TNE could be injected at a 23-fold higher dose than the LD50 of Nimotop injection with no obvious toxicity or side effects.CONCLUSION:NIMO-TNE is a promising formulation suitable for intravenous injection, is easy to prepare, and exhibits excellent safety.
Molecular interactions between drug and polymeric carriers are believed to be the key for high drug loading and better physical stability of micro-particles. However, molecular interactions between drug and polymer are still difficult to investigate using only experimental tools. In this study, high-loaded glipizide (GLP)/hydroxypropyl methylcellulose acetate succinate (HPMCAS) (1/1 w/w) micro-particles were prepared using an in situ pH-dependent solubility method. Molecular interactions within the micro-particles were investigated by integrated experimental and modeling techniques. The dissolution rate of GLP/HPMCAS micro-particles was significantly better than those of solid dispersions and physical mixtures. Scanning electron microscopy images showed that the polymer inhibited GLP recrystallization. Experimental (FTIR spectroscopy, differential scanning calorimetry, powder X-ray diffraction and nuclear magnetic resonance spectroscopy) and molecular dynamics simulation revealed that hydrogen-bonding was the key to the properties of the micro-particles. Our research developed high drug-loading GLP/HPMCAS micro-particles and investigated the interactions between drug and polymer at the molecular level. This integrated approach could be practical methodology for future formulation design.
外泌体广泛存在于各种体液中,是一种由细胞主动分泌的膜囊泡,直径为40~100 nm.外泌体中包含的生物大分子积极参与肿瘤细胞间的信息传递,参与并调控肿瘤的发生、发展.研究表明,将外泌体作为肿瘤检测的生物标记物是一种更加灵敏、准确的肿瘤诊断方法,且外泌体的结构和粒径赋予其天然的载药优势,是一种前景广阔的靶向药物载体.本文从外泌体的结构和功能入手,详细综述国内外关于外泌体在肿瘤靶向诊疗及药物传递系统开发中的研究进展.
Amorphous solid dispersion (SD) is an effective solubilization technique for water-insoluble drugs. However, physical stability issue of solid dispersions still heavily hindered the development of this technique. Traditional stability experiments need to be tested at least three to six months, which is time-consuming and unpredictable. In this research, a novel prediction model for physical stability of solid dispersion formulations was developed by machine learning techniques. 646 stability data points were collected and described by over 20 molecular descriptors. All data was classified into the training set (60%), validation set (20%), and testing set (20%) by the improved maximum dissimilarity algorithm (MD-FIS). Eight machine learning approaches were compared and random forest (RF) model achieved the best prediction accuracy (82.5%). Moreover, the RF models revealed the contribution of each input parameter, which provided us the theoretical guidance for solid dispersion formulations. Furthermore, the prediction model was confirmed by physical stability experiments of 17β-estradiol (ED)-PVP solid dispersions and the molecular mechanism was investigated by molecular modeling technique. In conclusion, an intelligent model was developed for the prediction of physical stability of solid dispersions, which benefit the rational formulation design of this technique. The integrated experimental, theoretical, modeling and data-driven AI methodology is also able to be used for future formulation development of other dosage forms.
To tailor the solid state properties of rivaroxaban (RXB), microparticles were prepared using an anti-solvent precipitation technique. A mixture of hydroxypropyl methylcellulose (HPMC) and bovine serum albumin (BSA) was used for modification of the crystallization process. The solid state properties of RXB microparticles were characterized by techniques including scanning electronic microscopy, differential scanning calorimetry and powder X-ray diffraction analysis. The microparticles were found to be small, ranging from 1 to 10 pm diameter with a good size distribution, and existed in a stable crystalline form. The nature of the drug-polymer/protein supramolecular interactions was explored by Fourier transform-infrared spectroscopy and fluorescence spectroscopy. Molecular docking was also conducted to validate the mechanism of the supramolecular interactions. Formation of the RXB-BSA complexes was mainly driven by van der Waals and hydrophobic interactions, which contributed to the particle size reduction. Hydrogen bonding between HPMC and RXB was responsible for polymorph control during crystallization. The results suggest that drug-polymer/protein supramolecular interactions play a vital role in modification of the solid state properties of poorly water soluble drugs. (C) 2018 Elsevier B.V. All rights reserved.