Which polymer is used in drug delivery?
Which polymer is used in drug delivery?
Among the synthetic and biodegradable polymers, aliphatic polyesters such as poly (glycolic acid), poly (lactic acid), poly (caprolactone) and polydioxanone, are most commonly used and applied to drug delivery systems.
Why are polymers used in drug delivery systems?
Polymers have played an integral role in the advancement of drug delivery technology by providing controlled release of therapeutic agents in constant doses over long periods, cyclic dosage, and tunable release of both hydrophilic and hydrophobic drugs.
What type of smart thermosensitive polymers are used in drug delivery?
The most commonly used LCST thermosensitive polymers include poly(N-isopropyl acrylamide), poly(N,N-diethylacrylamide), poly(N-vinylalkylamide), poly(N-vinylcaprolactam), phosphazene derivatives, pluronics, tetronics, polysaccharide derivatives, chitosan and PLGA–PEG–PLGA triblock copolymers11, 13.
What is polymer in pharmaceutical?
Pharmaceutical polymers include vinyl polymers, cellulose ethers, polyesters, silicones, polysaccharides and other biopolymers.
How do polymers release drugs?
For polymeric materials the mechanisms of drug release are normally directly linked to drug diffusion, dissolution, and degradation of the carrier matrix. However, other factors, such as interactions of the material and the drug, can also influence the release kinetics.
What are the properties and characteristics of smart polymers?
Smart polymers tend to have an all-or-nothing response, and are completely predictable, with the change being uniform throughout the material. They might alter their conformation, adhesiveness or water retention properties, and can return to their initial state when the stimulus ends.
Which of these polymer is used for controlled drug release in the body?
Most of the materials used in swelling-controlled release systems are based on hydrogels, which are polymers that will swell without dissolving when placed in water or other biological fluids. These hydrogels can absorb a great deal of fluid and, at equilibrium, typically comprise 60–90% fluid and only 10–30% polymer.
What are 4 types of polymers?
Terms. Synthetic polymers are human-made polymers. From the utility point of view, they can be classified into four main categories: thermoplastics, thermosets, elastomers, and synthetic fibers.
What are the general properties of polymers?
Some of the useful properties of various engineering polymers are high strength or modulus to weight ratios (light weight but comparatively stiff and strong), toughness, resilience, resistance to corrosion, lack of conductivity (heat and electrical), color, transparency, processing, and low cost.
How are polymers used in the drug delivery system?
Moreover, change in the drug is to polymer ratio of drug delivery system can help the release of drug from polymer matrix ( James et al., 2014 ). Hydrophilic polymers used alone can give a burst release of a drug. Hence, if it is mixed with a hydrophobic polymer, it can change the release profile of a drug.
How does the ratio of polymers affect the release profile?
The ratios in which both the polymers are mixed will affect the release profile of a drug from polymeric delivery system.
How are drug delivery devices used in medicine?
These drug delivery devices may be in the form of implants for controlled drug delivery. Polymers used in colloidal drug carrier systems, consisting of small particles, show great advantage in drug delivery systems because of optimized drug loading and releasing property.
How are polymers used to slow down dissolution?
In these systems, polymers hold the drug molecule in a way that the drug molecule is not exposed to dissolution media and thus can slow down rapid dissolution of drug molecule. There are two main mechanisms by which polymer allows slow dissolution of drug molecule in dissolution media—one is polymer dissolution and the other is polymer degradation.