Improve Blood Clotting Feature of Silicon Microneedle by Silver Coating

Microneedles have broad applications in biomedical and neural measurements, drug-delivery systems, and microbiological sample analysis. Blood compatibility is required when microneedle is used in blood related field. We proposed a method to improve the blood clotting feature of silicon microneedle by silver coating. We fabricated the silicon microneedle with and without silver coating by wet etching and metal sputtering and implemented the clotting test. The clotting test results indicated that silver coating plays more important role to improve the blood compatibility of silicon microneedle than surface structure.

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A novel multi-functionalized multicellular nanodelivery system for non-small cell lung cancer photochemotherapy

Journal of Nanobiotechnology ◽

10.1186/s12951-021-00977-3 ◽

2021 ◽

Vol 19 (1) ◽

Author(s):

Yongtai Zhang ◽

Qing Xia ◽

Tong Wu ◽

Zehui He ◽

Yanyan Li ◽

...

Keyword(s):

Drug Delivery ◽

Drug Delivery Systems ◽

Inner Core ◽

Blood Compatibility ◽

Drug Loading ◽

A549 Cells ◽

Honeycomb Structure ◽

Delivery Systems ◽

Antitumor Effects ◽

Apoptotic Pathway

Abstract Background A red blood cell membrane (RBCm)-derived drug delivery system allows prolonged circulation of an antitumor treatment and overcomes the issue of accelerated blood clearance induced by PEGylation. However, RBCm-derived drug delivery systems are limited by low drug-loading capacities and the lack of tumor-targeting ability. Thus, new designs of RBCm-based delivery systems are needed. Results Herein, we designed hyaluronic acid (HA)–hybridized RBCm (HA&RBCm)-coated lipid multichambered nanoparticles (HA&RBCm-LCNPs) to remedy the limitations of traditional RBCm drug delivery systems. The inner core co-assembled with phospholipid-regulated glycerol dioleate/water system in HA&RBCm-LCNPs met the required level of blood compatibility for intravenous administration. These newly designed nanocarriers had a honeycomb structure with abundant spaces that efficiently encapsulated paclitaxel and IR780 for photochemotherapy. The HA&RBCm coating allowed the nanocarriers to overcome the reticuloendothelial system barrier and enhanced the nanocarriers specificity to A549 cells with high levels of CD44. These properties enhanced the combinatorial antitumor effects of paclitaxel and IR780 associated with microtubule destruction and the mitochondrial apoptotic pathway. Conclusions The multifunctional HA&RBCm-LCNPs we designed expanded the functionality of RBCm and resulted in a vehicle for safe and efficient antitumor treatment. Graphical abstract

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Techniques For The Preparation of Tissue Samples Containing Injectable Polymer Microcapsules

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100120242 ◽

1985 ◽

Vol 43 ◽

pp. 710-711

Author(s):

G.E. Visscher ◽

R. L. Robison ◽

G. J. Argentieri

Keyword(s):

Drug Delivery ◽

Drug Delivery Systems ◽

Gastrocnemius Muscle ◽

Degradation Process ◽

Delivery Systems ◽

Tissue Reaction ◽

Electron Microscopic ◽

Tissue Samples ◽

Injectable Polymer ◽

Microscopic Techniques

The use of various bioerodable polymers as drug delivery systems has gained considerable interest in recent years. Among some of the shapes used as delivery systems are films, rods and microcapsules. The work presented here will deal with the techniques we have utilized for the analysis of the tissue reaction to and actual biodegradation of injectable microcapsules. This work has utilized light microscopic (LM), transmission (TEM) and scanning (SEM) electron microscopic techniques. The design of our studies has utilized methodology that would; 1. best characterize the actual degradation process without artifacts introduced by fixation procedures and 2. allow for reproducible results.In our studies, the gastrocnemius muscle of the rat was chosen as the injection site. Prior to the injection of microcapsules the skin above the sites was shaved and tattooed for later recognition and recovery. 1.0 cc syringes were loaded with the desired quantity of microcapsules and the vehicle (0.5% hydroxypropylmethycellulose) drawn up. The syringes were agitated to suspend the microcapsules in the injection vehicle.

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