The promise of chitosan microspheres in drug delivery systems

The development of controlled drug delivery systems for bone regeneration, especially microspheres, has become a research hotspot in recent years. Chitosan and its derivative O-carboxymethyl chitosan have been considered to be an effective way for controlled drug delivery due to their nontoxicity and biodegradability. Currently, most of the studies have researched on synthesizing and characterizing chitosan and O-carboxymethyl chitosan. However, few studies have focused on the differences between chitosan microspheres and O-carboxymethyl chitosan microspheres directly. In this study, chitosan and O-carboxymethyl chitosan microspheres were developed by water-in-oil emulsification cross-linking method using vanillin as the cross-linking agent, and then their physicochemical properties were evaluated by Fourier transform infrared spectroscopy, scanning electron microscopy, and in vitro release testing. The results showed that O-carboxymethyl chitosan was successfully modified by adding carboxymethyl group at the chitosan C6 position.The particle size of chitosan microspheres (50–90 µm) was significantly larger than that of O-carboxymethyl chitosan microspheres (10–50 µm), and the drug release profile of O-carboxymethyl chitosan microspheres showed larger initial burst release within the first day and sustained release at the fourth day, while chitosan microspheres showed sustained release at the seventh day. In addition, Cell Counting Kit-8 assay showed that MC3T3-E1 proliferated well and highly expressed the alkaline phosphatase marker protein on both chitosan and O-carboxymethyl chitosan microspheres. Overall, both chitosan and O-carboxymethyl chitosan microspheres showed good biocompatibility, and chitosan microspheres were superior to O-carboxymethyl chitosan microspheres. Moreover, the different drug release rates suggest that chitosan and O-carboxymethyl chitosan microspheres have the potential to be used for the repair of different bone defects.

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CHITOSAN MICROSPHERES FOR THE DELIVERY OF CHEMOTHERAPEUTIC AGENTS: PACLITAXEL AS A MODEL

Asian Journal of Pharmaceutical and Clinical Research ◽

10.22159/ajpcr.2017.v10i8.18765 ◽

2017 ◽

Vol 10 (8) ◽

pp. 15 ◽

Cited By ~ 3

Author(s):

Basma Yahya Al-najjar ◽

Saad Abdulrahman Hussain

Keyword(s):

Drug Delivery ◽

Targeted Delivery ◽

Drug Delivery Systems ◽

Delivery Systems ◽

Chemotherapeutic Agents ◽

Pharmacological Activities ◽

Chitosan Microspheres ◽

Biological Features ◽

Drug Molecules ◽

Targeted Delivery Systems

Chitosan has unique physicochemical and biological features that suggest it as a good candidate for the development of safe and effective drug delivery systems. Linking drug molecules with chitosan through a functional spacer enables formulation of prodrugs that have appropriate pharmacological activities at specific desired sites. The development of formulations of targeted delivery systems for the chemotherapeutic agents, especially those with unfavorable pharmacokinetic features, like paclitaxel (PTX), can potentially alleviate the systemic cytotoxicity as well as directing therapy to the specific lesions. The main aim of this literature review is to critically evaluate the use of chitosan microspheres as a drug delivery system to enhance PTX distribution and efficacy in specific targeted sites.

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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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