A review of stimuli-responsive nanocarriers for drug and gene delivery. J. Control. Rel. 126: 187-204

Department of Pharmaceutical Sciences, School of Pharmacy, Northeastern University, 110 Mugar Life Sciences Building, Boston, MA 02115, United States.
Journal of Controlled Release (Impact Factor: 7.26). 04/2008; 126(3):187-204. DOI: 10.1016/j.jconrel.2007.12.017
Source: PubMed

ABSTRACT Nanotechnology has shown tremendous promise in target-specific delivery of drugs and genes in the body. Although passive and active targeted-drug delivery has addressed a number of important issues, additional properties that can be included in nanocarrier systems to enhance the bioavailability of drugs at the disease site, and especially upon cellular internalization, are very important. A nanocarrier system incorporated with stimuli-responsive property (e.g., pH, temperature, or redox potential), for instance, would be amenable to address some of the systemic and intracellular delivery barriers. In this review, we discuss the role of stimuli-responsive nanocarrier systems for drug and gene delivery. The advancement in material science has led to design of a variety of materials, which are used for development of nanocarrier systems that can respond to biological stimuli. Temperature, pH, and hypoxia are examples of "triggers" at the diseased site that could be exploited with stimuli-responsive nanocarriers. With greater understanding of the difference between normal and pathological tissues and cells and parallel developments in material design, there is a highly promising role of stimuli-responsive nanocarriers for drug and gene delivery in the future.

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Available from: Mansoor Amiji, Aug 22, 2015
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    • "Typically such a control is obtained by changing the environmental conditions (e.g. ultrasound, UV–vis light, temperature, or pH of the bulk medium) [1] [2] [3] [4] [5]. Among these, temperature controlled drug release has received special interest due to its noninvasive character [6]. "
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    • "Nanometer scaled particles prepared with natural or synthetic polymers, lipids, or inorganic solids have been widely investigated as therapeutic carriers for anti-cancer drugs [1]. These particles, once injected into the bloodstream, can passively accumulate in tumors due to the leaky tumor vasculature and reduced lymphatic drainage, a phenomenon called enhanced permeability and retention (EPR) effect [2]. "
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    • "Stimuli-responsive drug delivery systems have recently been widely explored in attempt to address the problems in chemotherapy , such as the multidrug resistance, severe side effects, and metastasis [1] [2] [3] [4] [5] [6] [7] [8] [9]. Currently, more and more investigations focus on the noninvasive external stimuli responsive drug delivery and therapy because they allow remote, repetitive, and reliable tuning of drug release based on demand. "
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