Advances in Research on Cellulose-based Drug Carriers

Traditional drug delivery methods are prone to large fluctuations in drug concentration and require multiple frequent doses.As a green material with excellent properties,cellulose has been widely used as a drug carrier for the development and preparation of drug controlled-release system.Based on the mechanisms of slow drug release,such as dissolution-diffusion release,degradation release,and nanochannel-controlled release,the preparation methods of cellulose-based drug carriers are introduced in this paper.The applications of cellulose-based drug carriers in the fields of antitumor therapy,antibacterial therapy,chronic disease treatment,and viral disease treatment are summarized with the aim of providing a useful reference for research on cellulose-based drug carriers.

A hybrid genipin-crosslinked dual-sensitive hydrogel/nanostructured lipid carrier ocular drug delivery platform

The objective of this study was to develop a novel hybrid genipin-crosslinked dual-sensitive hydrogel/nanostructured lipid carrier(NLC) drug delivery platform. An ophthalmic antiinflammatory drug, baicalin(BN) was chosen as the model drug. BN –NLC was prepared using melt-emulsification combined with ultra-sonication technique. Additionally, a dual pH-and thermo-sensitive hydrogel composed of carboxymethyl chitosan(CMCS) and poloxamer 407(F127) was fabricated by a cross-linking reaction with a nontoxic crosslinker genipin(GP). GP-CMCS/F127 hydrogel was characterized by FTIR, NMR, XRD and SEM. The swelling studies showed GP-CMCS/F127 hydrogel was both pH-and thermo-sensitive. The results of in vitro release suggested BN –NLC gel can prolong the release of baicalin comparing with BN eye drops and BN –NLC. Ex vivo cornea permeation study was evaluated using Franz diffusion cells. The apparent permeability coefficient(Papp) of BN –NLC gel was much higher(4.46-fold) than that of BN eye drops. Through the determination of corneal hydration levels, BN –NLC gel was confirmed that had no significant irritation to cornea. Ex vivo precorneal retention experiments were carried out by a flow-through approach. The results indicated that the NLC-based hydrogel can prolong precorneal residence time. In conclusion, the hybrid NLCbased hydrogel has a promising potential for application in ocular drug delivery.

Dendritic macromolecules as nano-scale drug carriers:Phase solubility,in vitro drug release,hemolysis and cytotoxicity study

Potential of nanoscale triazine based dendritic macromolecules G1,G2 and G3 as solubility enhancers of drug was investigated.Effect of pH,concentration and generation of synthesized dendritic macromolecules on solubility of ketoprofen was studied.G3 dendrimer was further exploited as carrier for sustained release.Ketoprofen was encapsulated by inclusion complex method and also characterized by Flourier Transform Infrared spectroscopy.Sustained release study of ketoprofen from ketoprofen loaded dendrimer was carried out and compared with free ketoprofen.Hemolytic potential and Cytotoxicity assay using A-549 lung cancer cell lines revealed that synthesized triazine based dendritic macromolecules having more potential that commercially available PAMAM dendrimer.

Molecularly imprinted nanoparticles and their releasing properties, bio-distribution as drug carriers

Molecular imprinted nanoparticles(MINPs) can memorize the shape and functional group positions complementary to template, which account for the large drug loading capacity and slow drug release behavior as drug carriers. We synthesized MINPs via precipitation polymerization with vinblastine(VBL) as a model drug, and investigated the drug loading,releasing property in vitro and bio-distribution in vivo. The obtained MINPs, from 300 to 450 nm,had smooth surface and favorable dispersibility. The entrapment efficacy and drug loading capacity of VBL loaded MINPs(MINPs-VBL) were 83.25% and 8.72% respectively. In PBS(pH 7.4),MINPs-VBL showed sustained release behavior. The cumulative release percentage reached about 70% during 216 h and no burst release was observed. The releasing behavior of MINPsVBL in vitro conformed to the first-order kinetics model. MINPs-VBL and commercially available vinblastine sulfate injection(VBL injection) were injected via tail vein of SD rats respectively to investigate the bio-distribution. MINPs-VBL group showed higher concentration of VBL in tissues and serum than VBL injection group after 60 min, and the drug level in liver was the highest. MINPs-VBL exhibited liver targeting trend to some extent, which was based on the evaluation of drug targeting index(DTI) and drug selecting index(DSI).

Size,shape,charge and“stealthy”surface:Carrier properties affect the drug circulation time in vivo

The present review sets out to discuss recent developments of the effects and mechanisms of carrier properties on their circulation time.For most drugs,sufficient in vivo circulation time is the basis of high bioavailability.Drug carrier plays an irreplaceable role in helping drug avoid being quickly recognized and cleared by mononuclear phagocyte system,to give drug enough time to arrive at targeted organ and tissue to play its therapeutic effect.The physical and chemical properties of drug carriers,such as size,shape,surface charge and surface modification,would affect their in vivo circulation time,metabolic behavior and biodistribution.The final circulation time of carriers is determined by the balance between macrophage recognitions,blood vessel penetration and urine excretion.Therefore,when designing the drug delivery system,we should pay much attention to the properties of drug carriers to get enough in vivo circulation time to arrive at target site eventually.This article mainly reviews the effect of carrier size,size,surface charge and surface properties on its circulation time in vivo,and discusses the mechanism of these properties affecting circulation time.This review has reference significance for the research of long-circulation drug delivery system.

High-density lipoprotein as a potential carrier for delivery of a lipophilic antitumoral drug into hepatoma cells

AIM: To investigate the possibility of recombinant highdensity lipoprotein (rHDL) being a carrier for delivering antitumoral drug to hepatoma cells.METHODS: Recombinant complex of HDL and aclacinomycin(rHDL-ACM) was prepared by cosonication of apoproteins from HDL (Apo HDL) and ACM as well as phosphatidylcholine.Characteristics of the rHDL-ACM were elucidated by electrophoretic mobility, including the size of particles,morphology and entrapment efficiency. Binding activity of rHDL-ACM to human hepatoma cells was determined by competition assay in the presence of excess native HDL. The cytotoxicity of rHDL-ACM was assessed by MTT method.RESULTS: The density range of rHDL-ACM was 1.063-1.210g/mL, and the same as that of native HDL. The purity of all rHDL-ACM preparations was more than 92%.Encapsulated efficiencies of rHDL-ACM were more than90%. rHDL-ACM particles were typical sphere model of lipoproteins and heterogeneous in particle size. The average diameter was 31.26±5.62 nm by measure of 110rHDL-ACM particles in the range of diameter of lipoproteins.rHDL-ACM could bind on SMMC-7721 cells, and such binding could be competed against in the presence of excess native HDL. rHDL-ACM had same binding capacity as native HDL. The cellular uptake of rHDL-ACM by SMMC-7721 hepatoma cells was significantly higher than that of free ACM at the concentration range of 0.5-10 μg/mL(P＜0.01). Cytotoxicity of rHDL-ACM to SMMC-7721 cells was significantly higher than that of free ACM at concentration range of less than 5 μg/mL (P＜0.01) and IC50 of rHDL-ACM was lower than IC50 of free ACM(1.68 nmol/L vs3 nmol/L). Compared to L02 hepatocytes,a normal liver cell line, the cellular uptake of rHDL-ACM by SMMC-7721 cells was significantly higher (P＜0.01) and in a dose-dependent manner at the concentration range of 0.5-10 μg/mL. Cytotoxicity of the rHDL-ACM to SMMC-7721 cells was significantly higher than that to L02 cells at concentration range of 1-7.5 μg/mL (P＜0.01). IC50 for SMMC-7721 cells (1.68 nmol/L) was lower than that for L02 cells (5.68 nmol/L), showing a preferential cytotoxicity of rHDL-ACM for SMMC-7721 cells.CONCLUSION: rHDL-ACM complex keeps the basic physical and biological binding properties of native HDL and shows a preferential cytotoxicity for SMMC-7721hepatoma to normal L02 hepatocytes. HDL is a potential carrier for delivering lipophilic antitumoral drug to hepatoma cells.

A New Type of Nanogel Carrier based on Mixed Pluronic Loaded with Low-Dose Antitumor Drugs

To design a new type of antitumor nanodrug carrier with good biocompatibility, a drug delivery system with a 2.19% drug-loading rate, measured by high-performance liquid chromatography(HPLC), was prepared by membrane hydration using a mixed polymer: Pluronic■ F-127, which binds folic acid(FA), Pluronic■ F-68 and triptolide(TPL)(FA-F-127/F-68-TPL). As a control, another drug delivery system based on a single polymer(FA-F-127-TPL) with a 1.90% drug-loading rate was prepared by substituting F-68 with F-127. The average particle sizes of FA-F-127/F-68-TPL and FA-F-127-TPL measured by a particle size analyzer were 30.7 nm and 31.6 nm, respectively. Their morphology was observed by atomic force microscopy(AFM). The results showed that FA-F-127-TPL self-assembled into nanomicelles, whereas FA-F-127/F-68-TPL self-assembled into nanogels. An MTT assay showed that a very low concentration of FA-F-127/F-68-TPL or FA-F-127-TPL could significantly inhibit the proliferation of multidrug-resistant(MDR) breast cancer cells(MCF-7/ADR cells) and induce cell death. The effects were significantly different from those of free TPL(P < 0.01). Using the fluorescent probe Nile red(Nr) as the drug model, FA-F-127/F-68-Nr nanogels and FAF-127-Nr nanomicelles were prepared and then incubated with human hepatocarcinoma(HepG2) and MCF-7/ADR cells, and the fluorescence intensity in the cells was measured by a multifunctional microplate reader. The results indicated that both FA-F-127/F-68-Nr and FA-F-127-Nr had sustained release in the cells, but HepG2 and MCF-7/ADR cells exhibited significantly higher endocytosis of FA-F-127/F-68-Nr than that of FA-F-127-Nr(P < 0.01). A nude mice transplanted tumor model was prepared to monitor FA-F-127/F-68-Nr in the tumor tissue and organs by whole-body fluorescent imaging. The results showed that FA-F-127/F-68-Nr targeted tumor tissues. The prepared nanogels had small particle size, were easy to swallow, exhibited slow release property,targeted tumor cells, and could improve the antitumor effects of TPL;hence, they are ideal carriers for low-dose antineoplastic drugs.

Preparation and Characterization of Superparamagnetic Fe_3O_4/CNTs Nanocomposites Dual-drug Carrier

Fe3O4/carbon nanotubes（Fe3O4/CNTs） nanocomposites were prepared by polylol hightemperature decomposition of the precursor ferric chloride and CNTs in liquid triethylene glycol.After surface modification with hexanediamine,folate was covalently linked to the amine group of magnetic Fe3O4/CNTs nanocomposites.The products were characterized by Fourier-transform infrared spectroscopy,transmission electron microscopy,and vibrating sample magnetometry.Then Fe3O4/CNTs were used as a dual-drug carrier to co-delivery of the hydrophilic drug epirubicin hydrochloride and hydrophobic drug paclitaxel.The results indicated that the Fe3O4/CNTs had a favorable release property for epirubicin and paclitaxel,and thus had potential application in tumor-targeted combination chemotherapy.

Perspectives on bone-targeted nano-drug carriers for bone tumor treatment

Bone tumour is one of most common primary cancer which exhibits cancerous osteoblastic differentiation and malignant osteoid in patients.At present,chemotherapy(pre-and post-operative)is used as a standard treatment protocol for bone tumour.However,drugs used in the treatment of bone tumour induce high toxicity to normal tissues including anaemia,neutropenia,thrombocytopenia,and heart damage which further reduce the survival rate of patients.Therefore,there is an urgent need to develop a new therapeutic approach for the treatment such that it induce maximum cell killing effect in tumor cells while sparing the healthy bone cells.In this article,some new perspectives were provided on the development of bone-targeted nano-drug carriers for bone cancer treatment.We hope such discussions wouldencourage more detailed and careful studies to support product development of bone-targeted drug carriers for bone cancer treatment.

Preparation and Drug-release Behavior of β-TCP Ceramics Drug Carrier in vitro

β-TCP ceramics drug carrier was first prepared and characterized. SEM showed that β-TCP carrier was in porous amorphous structure with diameters around 10 μm. The physical properties including apparent porosity, volume-weight, tensile strength and the permeability were measured and the results indicated those properties fit the clinical usage of β-TCP drug carrier. Furthermore, drug release experiment in vitro showed that the carrier could prolong drug release in simulated body fluid which provides basis for the clinical use of β-TCP ceramics as drug carrier.

The application of open disk-like structures as model membrane and drug carriers

The objective of this review is to outline the application of bicelles(or called bilayer micelles)and bilayer nanodisks in pharmaceutics,pharmaceutical analysis and biochemistry.The application of open disk-like structures as model membrane and drug carrier has been described.The exploration of many reports in different fields suggested that these open disk-like structures have great potential in studying interactions between drug-membrane and structure/function studies of membrane-bound proteins.Furthermore,they could be applied as promising carriers for in vivo delivery of drugs,protein and peptide.

Research progress on pharmacological action and effective drug carrier of berberine

Berberine(BBR)is an isoquinoline alkaloid that can be extracted from the traditional Chinese medicine Huang Lian.It has anti-inflammatory,anti-cancer,protection of nerves,hypoglycemic,blood lipid,anti-oxidation,antibacterial and other effects.It can be used clinically to treat chronic colitis,bacterial vaginitis,rheumatoid arthritis,breast cancer,liver cancer,Alzheimer's disease,diabetes,obesity and other common diseases.This paper reviews the pharmacological effects of berberine and the research progress of effective drug carriers in order to provide new ideas for the clinical application of berberine.

Preparation and Characterization of Copolymer Micelles Formed by Poly(ethylene glycol)-Polylactide Block Copolymers as Novel Drug Carriers

Diblock copolymer poly(ethylene glycol) methyl ether–polylactide (MePEG–PLA) micelles were prepared by dialysis against water. Indomethacin (IMC) as a model drug was entrapped into the micelles by dialysis method. The critical micelle concentration (CMC) of the prepared micelles in distilled water investigated by fluorescence spectroscopy was 0.0051 mg/mL which is lower than that of common low molecular weight surfactants. The diameters of MePEGPLA micelles and IMC loaded MePEGPLA micelles in a number-averaged scale measured by dynamic light scattering were 52.4 and 53.7 nm respectively. The observation with transmission electron microscope and scanning electron microscope showed that the appearance of MePEGPLA micelles was in a spherical shape. The content of IMC incorporated in the core portion of the micelles was 18% (ω). The effects of the synthesis method of the copolymer on the polydispersity of the micelles and the yield of the micelles formation were discussed.

Preparation and characterization of biodegradable nanoparticles from methoxy poly(ethylene glycol)-poly(D,L-lactide)block copolymers as novel drug carriers

Methoxy poly(ethylene glycol)-poly(D,L-lactide) block copolymers (PEG-PLA) were prepared through ring-opening polymerization.The oil in water suspension method was used to prepare block copolymer micelles. The critical micelle concentration (CMC) by fluorescence spectroscopy was 0.0056 mg·ml -1 . The physical state of the inner core region of micelles was characterized with 1HNMR. The size of indomethacin (IMC) loaded micelles measured by dynamic light scattering (DLS) showed narrow monodisperse size distribution and the average diameters were less than 50 nm. In addition, the nanoparticles with relatively high drug loading content (DLC) were obtained.

Preparation of Star-Shaped Polylactic Acid Drug Carrier Nanoparticles

Drug carrier biocompatible and biodegradable nanoparticles of about 15 nm were prepared by solvent evaporation technique from star-shaped poly(D,L-lactide) synthesized using dipentaerythritol as core and Tin (II) ethylhexanoate as catalyst.

金纳米球-氧化石墨烯纳米药物载体的制备及抗癌性能

采用化学还原法制备了氧化石墨烯-金纳米球(GO-AuNP),利用透射电子显微镜(TEM)、紫外-分光光度计(UV-Vis)和激光粒度仪等对GO-AuNP进行了表征,并利用红外热成像仪对其光热性能进行了研究。将GO-AuNP负载抗癌药物盐酸阿霉素(DOX)制备成纳米药物复合物(GO-AuNP@DOX),并通过荧光分光光度计对DOX的负载和释放进行了检测;结果显示,GO-AuNP@DOX中DOX的释放在弱酸性环境下更优,并且在808 nm激光照射条件下pH=5.3时释放量可以达到30.51%。采用共聚焦显微镜分析了癌细胞对GO-AuNP@DOX的摄取能力;采用CCK-8细胞毒性实验分析了GO-AuNP@DOX的体外杀伤肿瘤细胞能力,细胞毒性实验证明GO-AuNP载体具备良好的生物相容性,体内抗肿瘤实验结果表明,荷瘤小鼠在化疗光热协同作用可以很好地抑制肿瘤生长。结果表明,GO-AuNP纳米药物载体具有光热转换能力优异、生物相容性优良的优点,其pH/近红外光谱(NIR)双重药物控释性能使药物载体在化疗-光热协同治疗肿瘤方面具有潜在的应用价值。

中医药联合医用水凝胶治疗疾病的策略及意义

背景:医用水凝胶是具有三维结构网络的新型功能高分子材料,具有出色的生物相容性,目前已在组织工程领域、药物载体领域有广泛研究,但基于组织工程探究医用水凝胶与中医药结合治疗疾病的研究还处于初期探索阶段。因此,通过对医用水凝胶机制作用的剖析,整合医用水凝胶与中医药在研究中联合应用的文章,进而更好地为科研工作者提供思路,对中医药与医用水凝胶联合应用具有重要意义。目的:基于组织工程研究探讨中医药联合医用水凝胶治疗疾病的策略及意义。方法:利用PubMed和中国知网数据库,检索有关中医药联合医用水凝胶在组织工程中应用的文献,检索时间为2010年1月至2022年11月,英文检索词为“hydrogel,traditional Chinese medicine,drug carrier,tissue engineering”,中文检索词为“医用水凝胶、中医药、药物载体、组织工程”。根据纳入与排除标准对所有文章进行初筛后,最终纳入61篇文章进行综述。结果与结论:①中医药联合医用水凝胶的应用虽然在关节内、组织器官内、软组织伤口和组织工程等方面有所涉及,但除了中医药结合水凝胶敷料在临床应用治疗软组织损伤外,其他方面尚处于基础实验阶段。②中医药联合医用水凝胶的发展有着巨大潜力和发展前景,但对于性能要求较高的凝胶在制造方面存在一定难度,理化性质精确掌握难度较大。③目前综合来看可注射水凝胶凭借着简便易用的特点,其在与中医药联合使用可延伸范围较广,可用于关节、器官和组织工程相关疾病的治疗;智能水凝胶有较高的灵敏度和可逆转化性也可满足特殊环境下的使用;将两者结合的中医药使用过程中还需要明确中药成分的作用机制。④中医药联合医用水凝胶治疗疾病的策略应着手于中医药对器官、组织、细胞的治疗作用联合适当种类的医用水凝胶进行匹配,可弥补传统中医给药方式和频繁给药的不足,在组织工程方面可以用水凝胶负载中药干预后的干细胞,或者同时负载中药和干细胞用于相关疾病的治疗。⑤在中医药联合医用水凝胶应用的未来研究中,还需要考虑:应当确保医用水凝胶生物性能可以量化,以不同材料不同制造工艺把握水凝胶特性,制造出所需要的符合应用条件的医用水凝胶;在中医药方面需要对已知中药单体、中药复方提取物的治疗效果和应用机制全面了解剖析,在更明了的机制下实现中医药与医用水凝胶更多更完美的结合;借助医学科技创新能力的不断提高,医用水凝胶可以创新性地结合中医药其他传统治疗方法比如针灸、推拿和拔罐等方式进行多角度运用。

静电纺丝构建中药控释系统的研究及应用

背景:静电纺丝多孔纳米纤维是一种具有优良性能和可设计性的材料,将传统中药与其联合构建新型中药控释系统是实现中药的控制释放和提高生物利用度的有效途径,具有广阔应用前景。目的:综述静电纺丝中药控释系统的构建方法及其在医学领域相关研究进展。方法:以“静电纺丝,中药,药物载体,释药系统,组织工程,敷料”为中文检索词,以“electrospinning,traditional Chinese medicine,drug carrier,drug delivery system,tissue engineering,dressing”为英文检索词,检索中国知网、PubMed和Web of Science数据库的关于静电纺丝中药控释系统的研究应用文献,检索时间范围为2013-2023年,最终纳入62篇文献进行综述分析。结果与结论:①构建电纺多孔纤维中药控释系统的关键要素为基质材料、中药成分和载药方式。②电纺多孔纤维中药控释系统的构建可依据应用场景和治疗目的进行,首先选定中药成分种类,然后依据药物特性选择与其适配的聚合物基体及溶液,最后依据释药需求设计纤维结构并采用适宜的载药方式。③目前在电纺纤维中药控释系统中所应用的药剂以易制备纺丝溶液的植物中药提取物为主,缺少动物中药和矿物中药的系统研究。④共混载药是研究应用最多的载药方式,且通过对溶液理化性质的优化和负载物质多样性的选择不断扩展其释药特性和适应场景;同轴、多轴及顺序纺丝等载药方式可以制备具有多层成分性质不同的复合纤维,具有广阔发展前景。⑤电纺纤维中药控释系统早期应用集中于医用敷料方面,利用中药活性成分的抗菌止血功能,近年来发现中药某些成分能促进细胞黏附增殖分化,开启了组织工程领域的探索研究。⑥目前对电纺多孔纤维中药控释系统的研究主要集中在对负载材料、工艺、理化性能、生物性能的表征和优化上,而对机制的研究较少,其在临床中的应用尚未普及,在体内的不良反应尚不明了,对其降解行为与释药行为的相互影响也缺乏研究。⑦未来研究中需要考虑:通过改善中药与纺丝溶剂的理化性能和加大中药活性成分的提纯以扩大非植物中药的应用范围,对中药成分的治疗效果和作用机制进行全面研究,并阐明控释系统的降解行为与释药行为的相互影响规律,在更准确的机制下实现中药与电纺纳米纤维更完美的联合和应用。

刺激响应型纳米载药系统用于抗多药耐药肿瘤的研究进展

目的 对新型刺激响应型纳米载药系统(nanodrug delivery systems, NDDS)在抗肿瘤多药耐药(multidrug resistance, MDR)中的应用进行综述。方法 通过查阅近年来国内外相关文献,对各种新型刺激响应型纳米载药系统在抗MDR型肿瘤方面的研究进展进行整理归纳。结果 目前已有多种内源性和外源性刺激响应型及多重响应型纳米载药系统构建成功并应用于抗MDR型肿瘤,取得了良好的疗效。结论 纳米载体具有生物相容性好,可修饰性强,载药量高等优点被广泛用于抗肿瘤药物递送领域。基于正常组织和肿瘤组织微环境的不同生理特性,合理设计开发新型刺激响应型纳米载药系统,可进一步提高药物递送的特异性和有效性,显著提升抗MDR型肿瘤的疗效。为后续的研究和开发提供有益参考。

人工智能与分子模拟在药物设计中的研究进展

随着现代药物研究的不断深入,传统计算机模拟已经不能满足未来药物设计实验的需求。分子模拟作为传统计算机模拟的经典技术之一,可以构造分析复杂的分子模型,研究分子运动的动态过程,但模拟结果受人为因素影响大,准确度较低。近年来,人工智能与分子模拟技术的融合成为药物设计研究的新方法。人工智能技术利用大数据筛选出对应的化合物进行分子模拟,并将模拟结果反馈给人工智能系统进行学习,不断优化人工神经网络。联用人工智能与分子模拟技术,提高了药物设计研究的效率,降低了人为因素对模拟结果的影响,增加了模拟结果的可信度。该文总结了当前国内外应用人工智能和分子模拟技术进行药物设计的研究成果,以期为未来药物研发从计算机辅助药物设计(CADD)向人工智能辅助药物研发(AIDD)的转变提供参考。