氧化石墨烯在骨组织工程中的应用

传统骨组织工程支架材料存在强度不足、生物活性低等缺点。近年来,碳纳米材料在骨再生方面展现出独特的优势。氧化石墨烯(graphene oxide, GO)是一种具有代表性的二维碳纳米材料,作为石墨烯的氧化形式,GO具有优异的力学性能、良好的生物相容性、大比表面积、易于改性等特点。GO不仅能够直接促进干细胞黏附、增殖和分化,还可以改善传统支架的机械性能、生物活性、抗菌能力、免疫调节能力等,基于GO的复合材料有望成为理想的骨再生支架。综述GO的物理化学性能、生物相容性、生物降解和清除等特性,总结GO作为涂层、控释材料和复合支架在骨组织工程中的最新应用,并对其未来研究方向进行展望。     

抗微生物作用的纳米材料研究新进展

通过对国内外抗微生物作用的纳米材料研究进行综述,总结几种最常应用的抗微生物作用的纳米材料的应用范围、作用原理及优缺点,为纳米材料的选用提供参考。目前抗微生物作用的纳米材料主要有金属元素型纳米材料、金属氧化物型纳米材料、非金属无机化合物型纳米材料、有机化合物型纳米材料和天然纳米材料等;纳米材料的抗微生物机制主要有催化反应与接触反应学说两种;有些纳米材料按现有制作方法和使用方法,具有一定的生物毒性。因此,今后应重视如何降低纳米材料的生物毒性以及进一步开发应用天然纳米材料的研究。     

纳米材料在组织修复及再生中的应用

从二十世纪八十年代开始,中国人开始有意识的接触纳米材料。目前,纳米材料已经在组织修复、肿瘤治疗等应用中取得突破性进展。本文主要综述了近年来纳米材料在骨骼、肿瘤、心脏等组织修复方面的具体应用。目前,组织工程领域广泛使用三维纳米支架材料模拟干细胞体内微环境的物理、化学特性,为组织修复、干细胞治疗效果提供保障。三维纳米材料可以调控造血干细胞、胚胎干细胞、间充质干细胞、神经干细胞等多种干细胞的体外增殖,在体外诱导干细胞向骨、软骨、神经或者肌肉等方向分化     

光及光热纳米材料在生物传感、药物靶向运输和生物成像中的应用

纳米材料是纳米科学技术的重要发展方向之一。纳米材料的结构赋予了其独特的光学性质,纳米尺寸方便其经EPR效应或表面修饰靶向肿瘤组织,并且部分纳米材料可吸收外部光源能量,将其转化为热能。因此,纳米材料在光学传感器、生物成像、药物靶向运输及肿瘤光热治疗中的应用十分广泛。综述主要分类介绍了光学纳米材料和光热纳米材料的优异特性,阐述了其在以上领域中的应用;最后,对纳米材料未来的发展作出了展望。     

检测纳米材料毒性的若干实验方法

纳米材料进入生命体和环境以后可能带来的生物安全问题需要定量的测定。现有的检测纳米材料生物安全性的方法大致可分为体内和体外实验两种,但是还没有证据表明既有的某个方法单独能作为一种检测所有纳米材料毒性的通用方法,也没有证据表明这些方法合在一起就能全面评估纳米材料的生物安全性。本文在总结既有的若干方法的同时,报道了一种基于rpsL基因的复制保真性来定量检测纳米材料毒性的方法。纳米材料对rpsL基因的体内体外复制过程保真性的影响均可方便地定量测定。     

浅析纳米材料新进展

纳米材料的出现极大地改变了人类的生活面貌,航空航天、医药等众多领域都应用了各种各样的纳米材料。纳米材料独特的性能使其自发现至今一直都是一个十分有活力的研究领域,吸引了众多科研工作者。本文简述了近年来纳米材料领域取得的进展,也对纳米材料的未来进行了展望。     

DNA-金属纳米材料在分子识别和药物递送中的应用

分子识别和药物递送对疾病的早期诊断和靶向治疗至关重要。DNA作为一种天然纳米分子，具有良好的生物相容性、分子识别性及序列可编程性等特点，因此在生物医学研究中受到广泛关注。然而，DNA纳米材料存在依赖于光响应系统且不能穿透细胞膜等缺点，导致单独使用无法满足实际应用的需求。近年来，涌现出大量DNA-金属纳米材料，这些复合材料具有光化学特性、组织穿透能力和药物装载能力等功能，克服了单一材料的缺陷，在生物传感、生物成像和药物靶向递送中表现出巨大的应用潜力。本文集中于3种近年热门的DNA-金属纳米材料（DNA-铜纳米材料、DNA-上转换纳米材料、DNA-金属有机框架纳米材料），依据DNA与各金属纳米材料的结合方式进行合理分类，介绍其在生物传感、生物成像和药物递送中的最新应用进展，并对未来发展方向进行了展望。     

医用金属及金属氧化物纳米材料的毒性研究

随着纳米科技的发展,纳米材料在各领域的应用日益增多。金属及金属氧化物纳米材料因其独特的物化性质,为多种疾病的诊治提供了崭新的解决途径。其中,贵金属金、银及应用最为广泛的铁所形成的纳米材料在医学领域应用甚广。纳米金及纳米银具有优异的抗菌效能,广泛用于伤口敷料、化妆品、食品等的制造中。除此之外,纳米金、纳米银及含铁的磁性纳米颗粒也用于疾病诊治方面,如肿瘤的诊断和治疗、生物传感器、生物成像等。但是,大部分金属纳米材料可对机体产生不良作用,因而了解金属纳米材料的毒性显得非常重要。为了在医学应用中更有效地利用金属纳米材料,必须探究其大小、表面化学、特殊性质及毒性。本文总结了这几种金属纳米材料的医学用途,概述了它们的体内外毒性,并分析了可能的毒性作用机制。     

工程纳米材料对污水生物处理影响的研究进展

工程纳米材料因其独特的物理化学性质被广泛应用于生产和生活中,但其潜在的风险正逐渐引起越来越多研究者的关注。目前国内外的研究主要探讨了工程纳米材料对模式微生物的毒性效应,但是对污水处理微生物的潜在影响尚缺乏系统和完整的报道。因此,本文综述了常见纳米材料对污水生物处理的影响,如碳、氮、磷的去除、甲烷化以及功能微生物种群结构演变等;同时还探讨了两种削减纳米银颗粒毒性的途径。综述内容为深入研究纳米材料对污水生物处理的潜在影响奠定了重要的理论基础。     

羧基化介孔二氧化硅纳米颗粒递送PD-L1抑制剂治疗膀胱癌的作用研究

摘要 目的：构建羧基化介孔二氧化硅纳米颗粒（COOH-MSN）递送PD-L1抑制剂治疗膀胱癌。方法：构建负载PD-L1抑制剂的COOH-MSNs,透射电镜检测纳米颗粒的特征,zeta电位分析仪检测纳米颗粒的电位变化;流式细胞术检测血液中T细胞和CD8⁺T细胞的比例;MTT实验检测细胞增殖;构建小鼠荷瘤模型,HE染色检测基本的病理学变化,免疫组化检测ki-67的表达。结果：透射电镜结果显示纳米颗粒呈圆形,直径约为100 nm;COOH-MSNs表面带负电荷,BSA呈强负电性,BSA包封后纳米材料整体负电荷增强;纳米材料可显著提高T细胞和CD8⁺T细胞的比例,并进一步抑制膀胱癌细胞的增殖;动物实验结果显示纳米材料可抑制移植瘤的生长,且移植瘤内淋巴细胞的数量显著升高;免疫组化结果显示相对于PD-L1抑制剂组,纳米材料组ki-67增殖指数显著减低;HE染色结果显示PD-L1抑制剂组肾组织内可观察到血管充血、扩张和较多炎细胞浸润,而纳米材料组肾组织损伤程度显著降低。结论：我们构建了一种负载有PD-L1抑制剂的COOH-MSNs,可有效激活抗肿瘤免疫反应,并降低对正常器官的损伤。     

Progress on carbon dots and hydroxyapatite based biocompatible luminescent nanomaterials for cancer theranostics

Despite the significant advancement in cancer diagnosis and therapy, a huge burden remains. Consequently, much research has been diverted on the development of multifunctional nanomaterials for improvement in conventional diagnosis and therapy. Luminescent nanomaterials offer a versatile platform for the development of such materials as their intrinsic photoluminescence (PL) property offers convergence of diagnosis as well as therapy at the same time. However, the clinical translation of nanomaterials faces various challenges, including biocompatibility and cost-effective scale up production. Thus, luminescent materials with facile synthesis approach along with intrinsic biocompatibility and anticancerous activity hold significant importance. As a result, carbon dots (CDs) and nanohydroxyapatite (nHA) have attracted much attention for the development of optical imaging probes. CDs are the newest members of the carbonaceous nanomaterials family that possess intrinsic luminescent and therapeutic properties, making them a promising candidate for cancer theranostic. Additionally, nHA is an excellent bioactive material due to its compositional similarity to the human bone matrix. The nHA crystal can efficiently host rare-earth elements to attain luminescent property, which can further be implemented for cancer theranostic applications. Herein, the development of CDs and nHA based nanomaterials as multifunctional agents for cancer has been briefly discussed. The emphasis has been given to different synthesis strategies leading to different morphologies and tunable PL spectra, followed by their diverse applications as biocompatible theranostic agents. Finally, the review has been summarized with the current challenges and future perspectives.     

Homologous recombination in Arabidopsis seeds along the track of energetic carbon ions

Nanomaterials are already used today and offer even greater use and benefits in the future. The progress of nanotechnology must be accompanied by investigations of their potential harmful effects. For airborne nanomaterials, lung toxicity is a major concern and obviously the particle size is discussed as a critical property directing adverse effects. While standard toxicological test methods are generally capable of detecting the toxic effects, the choice of relevant methods for nanomaterials is still discussed. We have investigated two genotoxic endpoints - alkaline Comet assay in lung tissue and micronucleation in polychromatic erythrocytes of the bone marrow - in a combined study 72 h after a single instillation of 18 μg gold nanoparticles (NP) into the trachea of male adult Wistar rats. The administration of three test materials differing only in their primary particle size (2, 20 and 200 nm) did not lead to relevant DNA damage in the mentioned tests. The measurement of clinical pathology parameters in bronchoalveolar lavage fluid (BALF) and blood indicated neither relevant local reactions in the animals' lungs nor adverse systemic effects. Minor histopathology findings occurred in the lung of the animals exposed to 20 nm and 200 nm sized nanomaterials. In conclusion, under the conditions of this study the different sized gold NP tested were non-genotoxic and showed no systemic and local adverse effects at the given dose.     

Nanomaterials as a potential environmental pollutant: Overview of existing risk assessment methodologies

The development and use of engineered nanomaterials is increasing rapidly and there are already a large number of consumer products containing nanomaterials. The possible release of nanomaterials from these products is still uncertain, as is their final fate and effects in the environment. Regulators need to deal with this lack of data when carrying out risk assessment and modify the existing risk assessment approaches to adapt them to the unique features of nanomaterials. Here we give an overview of various risk assessment approaches for nanomaterials developed worldwide, in which we describe their strengths and limitations, and have evaluated two of them, the Nano Risk Framework and the Precautionary Matrix for specific cases. Many properties of engineered nanomaterials are unknown and this causes deficiencies in the approaches studied. It is therefore essential to increase the present scarce data on nanomaterials released in the environment and close the gaps in the current methodologies to perform adequate risk assessment for nanomaterials.     

Nano-bio interactions: the implication of size-dependent biological effects of nanomaterials

Due to their many advantageous properties, nanomaterials(NMs) have been utilized in diverse consumer goods, industrial products, and for therapeutic purposes. This situation leads to a constant risk of exposure and uptake by the human body, which are highly dependent on nanomaterial size. Consequently, an improved understanding of the interactions between different sizes of nanomaterials and biological systems is needed to design safer and more clinically relevant nano systems. We discuss the sizedependent effects of nanomaterials in living organisms. Upon entry into biological systems, nanomaterials can translocate biological barriers, distribute to various tissues and elicit different toxic effects on organs, based on their size and location. The association of nanomaterial size with physiological structures within organs determines the site of accumulation of nanoparticles.In general, nanomaterials smaller than 20 nm tend to accumulate in the kidney while nanomaterials between 20 and 100 nm preferentially deposit in the liver. After accumulating in organs, nanomaterials can induce inflammation, damage structural integrity and ultimately result in organ dysfunction, which helps better understand the size-dependent dynamic processes and toxicity of nanomaterials in organisms. The enhanced permeability and retention effect of nanomaterials and the utility of this phenomenon in tumor therapy are also highlighted.     

人工纳米材料与生物膜相互作用机制及影响因素研究进展

人工纳米材料在水体中的环境行为与生物环境安全问题成为环境科学领域研究的热点,人工纳米材料与生物膜相互作用机制和影响因素是其中迫切需要研究解决的关键科学问题。本文主要探讨了人工纳米材料释放进入到水体中后对生物膜细菌活性、微生物群落结构、净污活性等的毒性效应,分析了人工纳米材料对生物膜的毒性作用机制及其影响因素,同时探讨了生物膜对人工纳米材料的吸附作用及机理,为深入研究人工纳米材料与生物膜的相互作用机制提供了重要的理论基础。     

纳米材料诱导自噬引发保护作用的研究进展

溶酶体-自噬系统在细胞对纳米材料的适应性反应中起到关键作用。自噬在保护细胞免受损伤和保持细胞稳定方面发挥重大作用,但纳米材料引起自噬的本质尚不清楚。纳米材料被细胞认为是外来入侵者,其积累将激活机体的清除机制,引发自噬。介绍了纳米材料诱导自噬发生的自我保护机制,综合分析了纳米材料对溶酶体-自噬系统的影响及其生物学效应。     

Ecotoxicological Effects of Nanomaterials on Earthworms: A Review

The concern regarding the ecotoxicological effects of nanomaterials in the terrestrial environment is increasing. Against this background, several studies have investigated the effects of different nanomaterials on various earthworm species. Since the earthworm is a representative invertebrate present in soil and occupies an important trophic level, many studies have focused on earthworms. Understanding how and why nanoparticles are toxic to organisms is important to nanotoxicologists and ecotoxicologists. We have collated information from studies on the toxicity of metal- and carbon-based nanomaterials to earthworms in the soil matrix, and trends in the adverse effects of nanomaterials on earthworms were analyzed. Most studies showed that the survival and growth of adult earthworms are negligibly affected by nanomaterials in the soil. However, many studies reported that nanomaterials may result in a reduction in the reproductive activity. This study presents an intensive overall view of the ecotoxicological impact of nanomaterials on earthworms at the organism, cellular, and molecular levels.     

金属纳米材料的生物化学制备及在生物医学领域的应用

近40年来,金属纳米材料发展迅猛,因其不同于宏观晶体的特殊性质,逐渐在各行业中起到了不可或缺的作用。当下人类面临资源、环境等日益严重的生态问题,因此金属纳米材料与生物学结合的绿色生态模式是大势所趋。本文重点综述了利用各种植物提取物、微生物以及蛋白质等生物材料作为还原剂,制备金属以及金属氧化物纳米材料的生物化学绿色合成方法。这些方法操作简单,制备的材料形貌尺寸不会产生太大变化。除此之外,生物材料的特定结构与金属纳米材料结合,通常会表现出协同或者新的理化和生理性能,以至于这些金属纳米材料在光热治疗及生物成像、抑菌及康复治愈和生物传感器及检测等生物医学领域产生了重大影响。金属纳米材料的生物化学制备会给未来纳米材料和生物学领域带来更多的交叉,会有更多跨学科工作者对其现存挑战来进行努力工作,并且在未来的医疗领域定会有金属纳米材料不可或缺的身影。