纳米技术在生物医学上的应用

分别论述了纳米技术在生物学和医药学上的应用，以及纳米生物技术与医学结合在诊断技术和治疗技术方面的应用，并列举了一些生物医学上应用的先进的纳米生物技术和纳米生物材料。     

羟基磷灰石纳米粒子表面修饰的研究进展

羟基磷灰石是人体骨骼和牙齿的主要无机成分,具有良好的生物相容性和生物活性,且能诱导骨组织的生长,促进组织缺损的修复,是性能优异的骨修复材料。近年来,纳米羟基磷灰石由于其独特的性能,在生物医学领域展现出新的应用功能。但是,为了发挥纳米羟基磷灰石独特的功能特性,常常需要对其进行表面修饰,以满足生物医学应用的条件和要求。从生物医学角度,针对羟基磷灰石纳米粒子在生物显影、DNA转染、药物递送、与高分子复合、促进成骨和抑菌等方面的应用,对羟基磷灰石纳米粒子的表面修饰研究进行论述,探讨相关表面修饰思路和技术及修饰应用效果。通过表面修饰,不仅可以提高羟基磷灰石纳米粒子的分散性和悬浮稳定性,提升药物装载能力和促进成骨能力,还可以赋予其生物显影能力、主动靶向功能和抑菌能力。总之,表面修饰是一种促进羟基磷灰石纳米粒子生物医学应用的有效手段。     

Degradability and Clearance of Inorganic Nanoparticles for Biomedical Applications

Inorganic nanoparticles with tunable and diverse properties hold tremendous potential in the field of nanomedicine, while having non‐negligible toxicity concerns in healthy tissues/organs that have resulted in their restricted clinical translation to date. In the past decade, the emergence of biodegradable or clearable inorganic nanoparticles has made it possible to completely solve this long‐standing conundrum. A comprehensive understanding of the design of these inorganic nanoparticles with their metabolic performance in the body is of crucial importance to advance clinical trials and expand their biological applications in disease diagnosis. Here, a diverse variety of biodegradable or clearable inorganic nanoparticles regarding considerations of the size, morphology, surface chemistry, and doping strategy are highlighted. Their pharmacokinetics, pathways of metabolism in the body, and time required for excretion are discussed. Some inorganic materials intrinsically responsive to various conditions in the tumor microenvironment are also introduced. Finally, an overview of the encountered challenges is provided along with an outlook for applying these inorganic nanoparticles toward future clinical translations.     

Ultrasmall Ag+-rich nanoclusters as highly efficient nanoreservoirs for bacterial killing

Metallic silver （Ag） and its ability to combat infection have been known since ancient history. In the wake of nanotechnology advancement, silver＇s efficacy to fight broad spectrum bacterial infections is further improved in the form of Ag nanoparticles （NPs）. Recent studies have ascribed the broad spectrum antimicrobial properties of Ag NPs to dissociation of Ag＊ ions from the NPs, which may not be entirely applicable when the size of Ag NPs decreases to the sub-2 nm range [denoted Ag nanoclusters （NCs）]. In this paper we report that ultrasmall glutathione （GSH）-protected Ag^＋-rich NCs （Ag^＋-R NCs for short, with a predominance of Ag＋ species in the NCs） have much higher antimicrobial activities towards both gram-negative and gram-positive bacteria than the reference NC, GSH-Ag^＋-R NCs. They have the same size and surface ligand, but with different oxidation states of the core silver. This interesting finding suggests that the undissociated Ag^＋-R NCs armed with abundant Ag^＋ ions on the surface are highly active in bacterial killing, which was not observed in the system of their larger counterpart, Ag NPs.     

Influence of Natural Crosslinkers on Chitosan Hydrogels for Potential Biomedical Applications

Chitosan (CH) is a very well-known biopolymer that has been widely used for the development of biomaterials with a wide range of applications in the biomedical field, such as the preparation of hydrogels, owing to its outstanding anti-inflammatory, antibacterial and antifungal properties, biocompatibility and biodegradability, although they present limited mechanical properties. Chemical crosslinking is one of the most recurrent strategies for the reinforcement of these structures and, above all, crosslinking with natural-origin compounds that do not compromise their biocompatibility is considered a hot topic in this research field. D-fructose (F), obtained from the hydrolyzation and further isomerization of starch, an abundant raw material and genipin (G), which is extracted from the fruits of Gardenia jasminoides Ellis are used as natural crosslinkers. Chitosan-based hydrogels crosslinked with each crosslinking agent are prepared and characterized through Fourier transform infrared (FTIR) spectroscopy, crosslinking and swelling degree determination, rheological, microstructural, and biological studies. The results demonstrate that crosslinking with G is more beneficial for chitosan-based hydrogels since these samples showed more compact structures and better rheological performance. Additionally, excellent biological in vitro behavior due to the crosslinking with G, unlike that of F.     

两维荧光光谱技术及最佳光谱分辨率设计

研究和发展了一种两维荧光光谱测量及成像技术,讨论获得两维空间离散点的最佳光谱分辨率的方法.该技术以棱镜色散原理为基础,利用微透镜阵列实现对样品的离散化照明,充分发挥光学系统固有的并行处理能力,实现了在一个面阵探测器上同时记录两维空间的荧光光谱图像.与逐点扫描方法相比,该技术的扫描效率随激发点数线性提高,具有快速测量、高空间和高光谱分辨的特点,可用于生物医学领域.     

光声显微成像技术的研究进展

光声成像作为一种兼具高光学对比度和大超声探测深度的新兴成像方法,突破了传统光学成像技术分辨率与成像深度相互制约的壁垒,获得了空前快速的发展,其中,光声显微成像技术继承了光声成像技术的优点,采用声学或光学聚焦的成像模式,可以实现高对比度、高分辨率的生物组织结构、分子与功能成像,在神经学、眼科、血管生物学和皮肤学等研究领域具有潜在应用价值。为此,首先介绍了光声成像技术的原理和分类,然后围绕光声显微成像(Photoacoustic microscopy, PAM)技术这一主题,重点综述了新型PAM技术的发展情况、PAM焦深（Depth of focus, DoF）延拓技术以及PAM的生物医学应用。最后,总结了PAM技术发展存在的挑战,并对未来发展方向进行了展望。     

自寻优Fuzzy控制在肢体外循环系统中的应用

设计了一种带预测参数的在线自寻优Fuzzy控制器,用于解决生物医学循环系统中存在的慢时变非线性等问题,对系统中温度、pH值、压力等参数进行控制,取得了很好的效果.     

Carbon Dot-Based Hydrogels: Preparations,Properties, and Applications (Small 17/2023)

Hydrogels have extremely high moisture content, which makes it very soft and excellently biocompatible. They have become an important soft material and have a wide range of applications in various fields such as biomedicine, bionic smart material, and electrochemistry. Carbon dot (CD)-based hydrogels are based on carbon dots (CDs) and auxiliary substances, forming a gel material with comprehensive properties of individual components. CDs embedding in hydrogels could not only solve their aggregation-caused quenching (ACQ) effect, but also manipulate the properties of hydrogels and even bring some novel properties, achieving a win–win situation. In this review, the preparation methods, formation mechanism, and properties of CD-based hydrogels, and their applications in biomedicine, sensing, adsorption, energy storage, and catalysis -are summarized. Finally, a brief discussion on future research directions of CD-based hydrogels will be given.