Polymers in Drug Delivery Systems

Polymers have played a major part in the development of drug delivery technology by proving controlled conditions of the release of medicine into one’s body and are becoming more and more significant in pharmaceutical operations. From using off-the-shelf resources, this topic of chemistry has grown far and wide powered by the advancements of chemical engineers. Improvements in drug delivery have now been envisaged dependant on the design of the polymers made and prepared to carry out specific tasks. (William B. Liechty, 2010)  

Polymers vary in their use from coatings for tablets and films to agents in liquids for controlling viscosity and flow. Polymers are mainly used in drug delivery systems to hide the unpleasant taste of medicine, to improve drug stability and to amend release properties. Today, about sixty million patients benefit from the new and improved drug delivery systems due to which receiving safer and more effective medicine is possible. (Shaik, Korsapati and Panati, 2012)

The advancement in drug delivery today starts with the usage of polymer carriers to the release of the drug in both pulsatile dose delivery products and through implanted reservoir systems. Although traditional drug delivery methods have played a huge part in the treatment of disease, the development of effective and explicit biological therapeutics has sky-rocked the motivation for intelligent drug delivery systems. It has also been pointed out that chemical engineering advancement in the development of drug delivery systems is extremely important with feedback control being a standard requirements of the systems. (William B. Liechty, 2010)

Developed systems must surmount many obstacles before they are clinically applied. An exceptionally intelligent drug delivery system must tackle the necessity for precise targeting, transport though cells and biocompatibility while incorporating components of responsive behaviour to physiological environments and feedback control. (William B. Liechty, 2010)

There has been remarkable growth due to the discovery and exploration of diffusion-controlled and solvent-activated formulations in drug delivery. Hydrogels and other polymer-based carriers have been created to transport medicine through hostile parts of the body. Polymers made with a controlled molecular structure can be created to be give a distinct response to different conditions due to having a good understanding of the mechanisms and the nature of the transitions. Polymers that have been combined with therapeutics can provide their own medicinal benefit or can be decomposable to make release kinetics better and to lessen the chance of carrier accumulation. Medicinal agents have been attached to polymers to alter transport or circulation as well as to permit inactive and active targeting. The latest drug delivery research using polymers has generated observant systems and carriers of polymers that give way to the delivery of therapeutics in the cytoplasm. (William B. Liechty, 2010)

A good example of the effectiveness of using polymers can be seen in the new generation of antibiotic medications. This has been shown by the large reduction of the amount of a certain medicine one has to take in one day. Before any of this, a certain medicine had to be taken about three or four times a day whereas now, the dosage is one per day. This is due to the control that polymers have been able to give the drugs: primarily by slower release of the drug making it more effective and therefore resulting in the patient having to take less doses.

Polymer degradation is the change in the properties of a polymer – tensile, strength, colour, shape etc. – based on or due to environmental factors such as light, heat and/or chemicals. Disintegrating reactions take place during the process, when the polymers have to endure heat, oxygen and mechanical stress, and during the life of the polymers when sunlight and oxygen are the most

important agencies. In more expert processing, degradation is possible through high energy radiation, atmospheric pollutants, ozone, biological action, mechanical stress, hydrolysis and numerous other influences. The research of these applications has made better use of the conventional instrumental analytical techniques and the spectrometric, chromatographic and thermal analysis methods have also been used. (Shaik, Korsapati and Panati, 2012)

Biodegradable polymers is quite an extensive topic of study. At present, the application of the of the numerous types of biodegradable polymers in surgery, pharmacology and therapy is deemed useful. In reality, restorable polymers are used in the healing process of wounds or in the growth of injured tissues and/or organs and to momentarily play their role. A restorable polymer sometimes also plays the role of a pharmaceutical storage providing a medicine to the blood at a constant rate for more or less a long period of time. (Shaik, Korsapati and Panati, 2012)

The study of polymer therapeutics has been very successful in the past few decades in discovering safe and effective ways of delivering medicine to treat a large amount of medical conditions. Polymers have a distinctive strength in their use towards drug delivery application which facilitates the advancement in creating new drug delivery systems which improve treatment and therapy. Even though drug delivery methods should be able to improve medicinal results, these techniques are sometimes needed to merely give way to therapy which is the case with gene therapy and the targeting of drugs. Drug delivery is also the smartest thing to do, as placing millions of medicine molecules in the blood or the stomach and permitting them to find their target with no control, is definitely a strategy of yesterday and not tomorrow. Polymers will make sure that the drugs will be distributed to only the places where it is needed in appropriate quantities and will result in less dosing efforts for the patient. Looking towards the future, research should go in the direction of finding out more about how polymers and polymer products are linked to biological systems. In recent years, many studies have investigated the novel chemical roots for drug delivery systems but often biocompatibility is overlooked until later in the development of the system resulting in the new devices being unable to cope and therefore, failing. Thought-out studies early in the development of the system will help to make sure that polymer-related breakthroughs result in safe and effective drug delivery systems. Polymers have been extremely helpful in assisting these efforts and will continue to facilitate them in the future. (Shaik, Korsapati and Panati, 2012) (William B. Liechty, 2010)

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