Alcohol medical applications

Polyvinyl alcohol (PVA), which is a water soluble polyhidroxy polymer, is one of the widely used synthetic polymers for a variety of medical applications [197] because of easy preparation, excellent chemical resistance, and physical properties. [198] But it has poor stability in water because of its highly hydrophilic character. Therefore, to overcome this problem PVA should be insolubilized by copolymerization [43], grafting [199], crosslinking [200], and blending [201], These processes may lead a decrease in the hydrophilic character of PVA. Because of this reason these processes should be carried out in the presence of hydrophilic polymers. Polyfyinyl pyrrolidone), PVP, is one of the hydrophilic, biocompatible polymer and it is used in many biomedical applications [202] and separation processes to increase the hydrophilic character of the blended polymeric materials [203,204], An important factor in the development of new materials based on polymeric blends is the miscibility between the polymers in the mixture, because the degree of miscibility is directly related to the final properties of polymeric blends [205],... 

Ultimately, the cultivation, sale, and possession of cannabis is illegal at present in most places. Individuals who use it for whatever purpose in most areas carry the risk of arrest and prosecution. From the perspective of addictiveness, it seems inconsistent that cannabis use is prohibited, while the use of alcohol and nicotine are permitted. Apart from arguments about the recreational use of cannabis, resistance to its medical application is even more inconsistent. For example, the opioids carry some risk for dependence, but with medical supervision they are useful medications and their abuse is minimal (Joranson et al. 2000). Whether use of cannabis is to be permitted and for which purposes (medical or recreational) remains to be collectively decided by society and the legislators it appoints. 

An approach published in 2001 based on research out of the Klibanov laboratory at MIT is to use ethanol [5]. Ethanol, isopropanol, and other alcohols have long been used successfully as penetration enhancers for medical applications. Ethanol is one of the first molecules to have been used as a transdermal enhancer, because its effects are so easily and well characterized and its systemic and local toxicities are understood. It is currently contained in commercial delivery systems for estradiol [17] and other bioactive molecules. Ethanol and isopropanol have been used in a variety of studies based on their effects on drug transport. More applications can be found in the patent literature [18]. 

Besides sterilization, chemical resistance is generally an important attribute that blends and alloys in medical applications must possess. Key chemical agents that must be evaluated include saline solution, isopropyl alcohol, ethyl alcohol, betadyne, chlorine bleach, and lipids. 

Ethanol, a sedative-hypnotic drug, is the most important alcohol of pharmacologic interest. It has few medical applications, but its abuse as a recreational drug is responsible for major medical and socioeconomic problems. Other alcohols of toxicologic importance are methanol and ethylene glycol. 

PEI has a better chemical resistance than most noncrystalline polymers. It is resistant to acetic and hydrochloric acids, weak nitric and sulfuric acids, and alcohol. The unfilled polymer complies with FDA regulations and can be used in food and medical applications. Table 2.21 lists the compatibility of PEI with selected corrodents. Reference [1] provides a more comprehensive listing. 

Migration measurement is eomplieated by the presenee of additional media into whieh the plastieiier migrates. These media have a eomplex and a variable eomposition beeause they are either food produets or various bo(fy fluids (saliva, blood, ete.). It is usually not vety praetical to study real materials but simulants must be developed to resemble a group of produets. Food produets differ in eomposition with special attention given to fats, solvents (e.g., alcohol), adds because these components of food may increase the absorption or extraction of plasticizers. In evaluation of plasticizers for medical applications, interaction of a plasticizer with body fluids and their components is important since it may affect biocompatibihty (see more on this aspect in Section 13.18) but the actual extracting ability of body fluid is also important because it affects the quantity of migrated substance (see more on this aspect in Section 13.26). 

Chemical compatibility/resistance is of particular importance to medical applications. Disinfectants represent one class of chemicals that includes Betadine , glutaraldehyde-based disinfectants, sodium hypochlorite solution (5 %), ethyl alcohol, isopropyl alcohol, hydrogen peroxide (3 %), and ammonium chloride-based disinfectant. Additionally, resistance to methyl ethyl ketone, saline solution, lipid-based compounds, and fatty acids is important. 

Citrates are plasticizer alcohol esters of citric acid. They are used in food-contact and medical applications due to their perceived low toxicity. 

Polymer types that can be formulated into FRRPP-based homogeneous nanospheres for medical applications include thermoreversible hydrogels, such as linear and cross-linked copolymers based in methacrylic acid, n-isopropyl acrylamide (NIPAM), vinyl alcohol from vinyl acetate. Nanospheres from more conventional polymers, such as polystyrene, can be used as model materials as well. It should be noted that nanoparticles are of the same size as viruses thus, they are all capable of generating or becoming viruses themselves. It is important to accompany studies of formation and application of nanoparticles for medical applications with studies based on less complicated model materials. 

Abstract A review is presented of the main types of bioresorbable or bioabsorbable materials used in medical applications such as drug delivery. Groups discussed include aliphatic polyesters, polyanhydrides, poly(ortho esters) (POE), polyphosphazenes, poly(amino acids) and pseudo poly(amino acids), polyalkylcyanoacrylates, poly(propylene fumarate) (PPF), poloxamers, poly(p-dioxanone) (PPDO) and polyvinyl alcohol (PVA). 

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