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181.
由于具备组织穿透深度深和时空分辨率高等优势, 近年来近红外二区(Near-infrared-Ⅱ, NIR-Ⅱ, 1000~1700 nm)荧光成像技术得到了快速发展, 其在肿瘤临床诊断和治疗的潜力更是引发了广泛关注. 本文首先阐释了NIR-Ⅱ窗口荧光成像的原理及其优势, 随后根据结构分类归纳总结了现有荧光团的特征, 重点介绍了荧光探针在性能优化上的进展以及在肿瘤早期检测、 术中导航和光疗中的应用, 最后讨论了现有NIR-Ⅱ 荧光探针的局限以及临床转化面临的挑战, 并对未来的发展方向进行了展望. 相似文献
182.
Drug carrier materials need to possess good biological safety. Presently, most biosafety evaluation studies use rodent animal models, including rats and rabbits. However, the cost of raising these animals is relatively high and the experimental period is long. Caenorhabditis elegans(C. elegans) presents an ideal toxicological evaluation model due to its simple structure, easy cultivation, short life cycle, and evolutionary conservation. In this paper, we used C. elegans to test the biological safety of our pH-responsive carrier system(FFPFF self-assembling into a nanosphere structure, FFPFF Nps), which was designed for anti-tumor drug delivery. Our results showed that exposure to high doses of FFPFF Nps did not have a significant impact on the survival rate, growth, development, movement, and reproduction of C. elegans. The preliminary evaluation of the overall biological model of C. elegans shows that FFPFF Nps has good biological safety and warrants further study. 相似文献
183.
Jonas Volmer S. Hamidreza Arabi Christian Henning Marcus A. Glomb Dariush Hinderberger 《Macromolecular bioscience》2023,23(3):2200487
The changes of technological properties of albumin-based hydrogels induced by increasing degrees of post-translational modification of the protein are reported. Maillard-type modification of amino acids arginine and lysine of albumin is achieved through glyoxal as an α-dicarbonyl compound. The degrees of modification are fine-tuned using different molar ratios of glyoxal. Hydrogels are thermally induced by heating highly concentrated precursor solutions above the protein's denaturation temperature. While the post-translational modifications are determined and quantified with mass spectrometry, continuous-wave (CW) electron paramagnetic resonance (EPR) spectroscopy shed light on the protein fatty acid binding capacity and changes thereof in solution and in the gel state. The viscoelastic behavior is characterized as a measure of the physical strength of the hydrogels. On the nanoscopic level, the modified albumins in low concentration solution reveal lower binding capacities with increasing degrees of modification. On the contrary, in the gel state, the binding capacity remains constant at all degrees of modifications. This indicates that the loss of fatty acid binding capacity for individual albumin molecules is partially compensated by new binding sites in the gel state, potentially formed by modified amino acids. Such, albumin glycation offers a fine-tuning method of technological and nanoscopic properties of these gels. 相似文献
184.
Electrospinning is a well-known technique since 1544 to fabricate nanofibers using different materials like polymers, metals oxides, proteins, and many more. In recent years, electrospinning has become the most popular technique for manufacturing nanofibers due to its ease of use and economic viability. Nanofibers have remarkable properties like high surface-to-volume ratio, variable pore size distribution (10–100 nm), high porosity, low density, and are suitable for surface functionalization. Therefore, electrospun nanofibers have been utilized for numerous applications in the pharmaceutical and biomedical field like tissue engineering, scaffolds, grafts, drug delivery, and so on. In this review article, we will be focusing on the versatility, current scenario, and future endeavors of electrospun nanofibers for various biomedical applications. This review discusses the properties of nanofibers, the background of the electrospinning technique, and its emergence in chronological order. It also covers the various types of electrospinning methods and their mechanism, further elaborating the factors affecting the properties of nanofibers, and applications in tissue engineering, drug delivery, nanofibers as biosensor, skin cancer treatment, and magnetic nanofibers. 相似文献
185.
The main aim of this study is to formulate the combination of the bioactive composite containing chitosan/β -tricalcium phosphate (CH/β-TCP) as potential drug delivery platforms for the sustained release of antibiotics. Herein the mode of amoxicillin (AMX) maintained in the β-TCP/chitosan composite was characterized using XRD, FT-IR to confirm the phase purity and functional groups. SEM was used to examine the size and shape of particles. The SEM images of the biocomposites after drug release confirmed that they are biodegradable. In vitro drug release experiments in PBS (pH 7.4) revealed a sustained release profile in a neutral medium. Drug release profiles were evaluated according to five different kinetic models including Zero Order, First Order, Higuchi, Hixon Crowel, and Korsmeyer-Peppas. The release profile was best expressed by the Korsmeyer Peppas model because the results showed high linearity. Overall, the positive effect of chitosan coating on the drug elution profile of β-TCP as carriers for the controlled delivery of antibiotics was regarded as biocompatible for the controlled drug delivery system. 相似文献
186.
Ultrasound has been recognized as an exciting tool to enhance the therapeutic efficacy in tumor chemotherapy owing to the triggered drug release, facilitated intracellular drug delivery, and improved spatial precision. Aiming for a precise localized drug delivery, novel dendritic polyurethane-based prodrug (DOX-DPU-PEG) was fabricated with a drug content of 18.9% here by conjugating DOX onto the end groups of the functionalized dendritic polyurethane via acid-labile imine bonds. It could easily form unimolecular micelles around 38 nm. Compared with the non-covalently drug-loaded unimolecular micelles (DOX@Ph-DPU-PEG), they showed excellent pH/ultrasound dual-triggered drug release performance, with drug leakage of only 4% at pH 7.4, but cumulative release of 14% and 88% at pH 5.0 without and with ultrasound, respectively. The ultrasound responsiveness was attributed to the unique strawberry-shaped topological structure of the DOX-DPU-PEG, in which DOX was embedded in the skin layer of the hydrophobic DPU cores. With ultrasound, the DOX-DPU-PEG unimolecular micelles possessed enhanced tumor growth inhibition than free DOX but showed no obvious cytotoxicity on the tumor cells without ultrasound. Such feature makes them promising potential for precise localized drug delivery. 相似文献
187.
Megan L. Qualls Dr. Jinchao Lou Dillon P. McBee Prof. Joshua A. Baccile Prof. Michael D. Best 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(45):e202201164
Liposomes are effective therapeutic delivery nanocarriers due to their ability to encapsulate and enhance the pharmacokinetic properties of a wide range of therapeutics. Two primary areas in which improvement is needed for liposomal drug delivery is to enhance the ability to infiltrate cells and to facilitate derivatization of the liposome surface. Herein, we report a liposome platform incorporating a cyclic disulfide lipid (CDL) for the dual purpose of enhancing cell entry and functionalizing the liposome membrane through thiol-disulfide exchange. In order to accomplish this, CDL-1 and CDL-2 , composed of lipoic acid (LA) or asparagusic acid (AA) appended to a lipid scaffold, were designed and synthesized. A fluorescence-based microplate immobilization assay was implemented to show that these compounds enable convenient membrane decoration through reaction with thiol-functionalized small molecules. Additionally, fluorescence microscopy experiments indicated dramatic enhancements in cellular delivery when CDLs were incorporated within liposomes. These results demonstrate that multifunctional CDLs serve as an exciting liposome system for surface decoration and enhanced cellular delivery. 相似文献
188.
Dr. Lina Xie Dr. Le Shi Dr. Kai Xiong Dr. Ruilin Guan Prof. Dr. Yu Chen Prof. Dr. Jiangang Long Prof. Liangnian Ji Prof. Dr. Hui Chao 《欧洲无机化学杂志》2023,26(15):e202300001
Two novel unsymmetrical Ir(III) complexes [Ir(ppy)2(N N)Cl2] (N N=2-(pyrazin-2-yl)naphtha[1,2-e][1,2,4]triazine, Ir1 ; 2-(pyrazin-2-yl)-4b,4b’-dihydroaceanthryleno[1,2-e][1,2,4]triazine, Ir2 ) were developed as chemotherapy agents. Ir1 was mainly located in mitochondria. In contrast, Ir2 accumulated in mitochondria but subsequently migrated to the nucleus. Ir1 and Ir2 showed cytotoxicity toward cancerous cells, especially the cisplatin-resistant ones, indicating their ability to overcome cisplatin resistance. Although both Ir1 and Ir2 disrupted mitochondrial metabolism, they showed different cell death mechanisms. Ir1 induced mitochondria-mediated apoptosis in cisplatin-resistant A549R cells. Ir2 was demonstrated to cause PARP-1 activated necroptosis in A549R cells. This study provides an experimental basis for the rational design of metal-based chemotherapeutic drugs. 相似文献
189.
Jeladhara Sobhanan Abdulaziz Anas Vasudevanpillai Biju 《Chemical record (New York, N.Y.)》2023,23(3):e202380301
Bioconjugated nanomaterials replace molecular probes in bioanalysis and bioimaging in vitro and in vivo. Nanoparticles of silica, metals, semiconductors, polymers, and supramolecular systems, conjugated with contrast agents and drugs for image-guided (MRI, fluorescence, PET, Raman, SPECT, photodynamic, photothermal, and photoacoustic) therapy infiltrate into preclinical and clinical settings. Small bioactive molecules like peptides, proteins, or DNA conjugated to the surfaces of drugs or probes help us to interface them with cells and tissues. Nevertheless, the toxicity and pharmacokinetics of nanodrugs, nanoprobes, and their components become the clinical barriers, underscoring the significance of developing biocompatible next-generation drugs and contrast agents. This account provides state-of-the-art advancements in the preparation and biological applications of bioconjugated nanomaterials and their molecular, cell, and in vivo applications. It focuses on the preparation, bioimaging, and bioanalytical applications of monomodal and multimodal nanoprobes composed of quantum dots, quantum clusters, iron oxide nanoparticles, and a few rare earth metal ion complexes. 相似文献
190.