Controlled drug delivery vehicles

ELP-based triblock copolypeptides have also been used to produce stimulus-responsive micelles, and Chaikof and coworkers envisioned the possible application of these micelles as controlled drug delivery vehicles. These amphiphilic triblock copolymers were constructed from two identical hydrophobic ELP endblocks and a hydrophilic ELP midblock. Below the transition temperature, loose and monodispersed micelles were formed that reversibly contracted upon heating, leading to more compact micelles with a reduced size [90]. 

Rajan, M., Raj, V., Al-Arfaj, A. A., Murugan, A. M. (2013). H3raluronidase enzyme core-5-fluorouracil-loaded chitosan-PEG-gelatin polymer nanocomposites as targeted and controlled drug delivery vehicles, Int r. Pharm.. 453(2), 514-522. 

Silica [244] Controlled drug delivery vehicle for bone tissue... 

Figure 1.7 Micelles of thermo-responsive polymers used as controlled drug delivery vehicle.

DW Urry, CM Harris, CX Luan, CH Luan, C Gowda, TM Parker, SQ Peng, J Xu. Transductional protein-based polymers as new controlled-release vehicles. In K Park, ed. Controlled Drug Delivery Challenges and Strategies. Washington, DC ACS, 1997, pp 405-437. 

Shinkai and coworkers prepared numerous novel amphiphilic crowns (Shinkai, 1990) and incorporated them into membranes, formed membranes from them, or used them in liquid crystalline assemblies to control properties (He et al., 1990). Interest in this area continues. Four chiral amphiphilic crown ethers were recently reported that recognize enantiomeric amino acids when examined as Langmuir films (Badis et al., 2004). Finally, it is interesting to note that liposomes formed from amphiphiles (e.g., crown ethers) having neutral headgroups (i. e., niosomes) have been studied as drug delivery vehicles (Uchegbu and Vyas, 1998). 

Regardless of the drug release mechanism, utilizing polymers as a drug delivery vehicle enables controlled and sustained release of the drug. Moreover, for a DES, this has the added benefit of localized delivery to a specific target, that is, the stented artery area. 

Previous Investigations in the field of controlled drug delivery have centered on the design and In vitro testing of the device. Animal experimentation has been largely limited to reports on the temporal pharmacodynamic performance of the drugs released from the implanted. Inserted, or surface-applied polymer vehicles. Few studies have attempted to provide details of the kinetic... 

A membrane-controlled drug delivery device was developed to release tetracycline at zero-order rates. The tetracycline delivery vehicle Is a trllamlnate disk consisting of core and coating membranes fabricated from a series of 2-hydroxyethyl-methacrylate and methylmethacrylate copolymers. Appropriate adjustment of the monomer composition ratio Imparts a hydrophobic nature to the copolymer outer coating membrane (relative to the... 

Meilander, N.J. et al., Lipid-based microtubular drug delivery vehicles, Journal of Controlled Release, 2002, 71, 141-152. 

If they absorb at a predictable rate, they can be used as vehicles for controlled drug delivery (e.g., anesthetics for relieving local pain). 

Khangtragool et al. studied about chitosan as an ocular drug delivery vehicle for vancomycin. Their study demonstrated quite clearly that a 0.3% w/v chitosan solution in 1% aqueous L-lactic acid offers several advantages as a vehicle for the ophthalmic delivery of vancomycin. These advantages include controlled drug delivery for the eye, biocompatibility, storage stability, and cost... 

Polyacrylic acid (PAA] is a biodegradable water-soluble polymer with a wide range of medicinal applications and is considered pharmaceutically safe. They are used for oral and mucosal contact applications in the form of controlled release tablets, oral suspensions, and bioadhesives. The unique property of PAA is that it exists as a liquid at pH 5 and as a gel at pH 7. Permeation of cations into the gelled polymer converts the gel back to a liquid. It is an ideal polymer used for ocular delivery of ribozymes to the corneal epithelium as a drug delivery vehicle. 

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