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Allergic Contact Dermatitis from Rubber and Plastic Gloves
Published in Robert N. Phalen, Howard I. Maibach, Protective Gloves for Occupational Use, 2023
Completely cured plastic materials are not generally considered sensitizers, and polyvinyl chloride (PVC), polyethylene or polyethylene (PE), polyvinyl acetate (PVAc), polyvinyl alcohol, and other materials used in plastic gloves rarely cause allergic contact dermatitis. The use of plastic materials for personal protective equipment has become common since the 1950s, but in most countries, plastic gloves are possibly less used than rubber gloves. One reason for this may still be that the users find plastic gloves less comfortable because they are not always as soft and pliable as rubber gloves and do not completely follow the contours of the hands. Accordingly, most reports on allergic contact eczema from plastic gloves are based on only one or a few cases.5 In a German study, 31 patients investigated from 1969 to 1984 were sensitized from the use of rubber or vinyl gloves; 10% of them were allergic to vinyl gloves.32 Similar results were obtained in a Finnish study: 5 (7%) of 68 patients were sensitized due to the use of PVC gloves.2 Since then, only three definite cases of vinyl glove allergy have been diagnosed at the Finnish Institute of Occupational Health (FIOH).33,34 In a Japanese questionnaire study, however, 31 (51%) of 61 women who had developed contact dermatitis from using household gloves linked their skin symptoms with the use of vinyl gloves and 26 (43%) with rubber gloves. Irritation was suggested as the cause of the vinyl glove dermatitis, not an allergy to the material itself.35
Binders in Pharmaceutical Granulation
Published in Dilip M. Parikh, Handbook of Pharmaceutical Granulation Technology, 2021
Polyvinyl Alcohol is a well-established polymer in the pharmaceutical industry mainly due to its unique properties, such as excellent adhesive strength, film formation, and chemical stability (moisture and oxygen barrier properties). Its most widely used applications are tablet coating and wet granulation, but PVA also plays an important role in solubility enhancement, transdermal patches, and emulsions. This polymer is produced through the hydrolysis of polyvinyl acetate and typical pharmaceutical grades are partially hydrolyzed materials. PVA is available in a variety of viscosity grades and grades from 10 to 100 millipascal second (mPa.s) lend themselves for tablet granulation processes. PVA’s are water-soluble polymers. It is reported that they form softer granulations, which yield tablets that do not harden with age [9]. They can also be used in melt granulation applications. In addition, polyvinyl alcohol-polyethylene glycol graft copolymer was also developed as a flexible, low viscosity, peroxide-free polymer for immediate release film-forming agent. Studies have found that this graft copolymer has the superior binding performance to HPMC while the performance was comparable to PVP [10].
Determination of Antiviral Activity
Published in Adorjan Aszalos, Modern Analysis of Antibiotics, 2020
In this experiment, we infect intravaginally adult (22–25 g) female Swiss mice with strain E194 of virus. The infection is achieved by first swabbing the vaginal area of the mice with dry sterile cotton swabs, then again swabbing the area with a virus-impregnated swab, holding the swab on the area approximately 15 sec to allow the infection to become established. For this initial experiment, 5, 1, and 0.5% concentrations of substance A are used in a “standard” topical vehicle; we have found that 1.4% type III polyvinyl alcohol (PVA) works quite well in penetrating the infected area, remaining on the infected area a reasonable period of time, and will usually readily release the test material to the infected cell. If efficacy is found using this vehicle, then extensive studies will be carried out comparing the material’s antiviral effectiveness in a variety of potentially appropriate vehicles.
Antiviral and antibacterial potential of electrosprayed PVA/PLGA nanoparticles loaded with chlorogenic acid for the management of coronavirus and Pseudomonas aeruginosa lung infection
Published in Artificial Cells, Nanomedicine, and Biotechnology, 2023
Asmaa Saleh, Dalia H. Abdelkader, Thanaa A. El-Masry, Duaa Eliwa, Badriyah Alotaibi, Walaa A. Negm, Engy Elekhnawy
Polyvinyl alcohol (PVA) is a non-toxic polymer approved for use in several devices, including contact lenses and artificial organs [16]. PVA is valuable for drug delivery formulations intended for alternate administration routes because of its advantages, biocompatibility and bioadhesiveness [18]. Furthermore, PVA's high water solubility offers additional advantages over conventional or complex drug preparation techniques, allowing safe preparation methods that do not harm pharmaceuticals during formulation [16]. Due to its biodegradability and biocompatibility, poly lactic-co-glycolic acid (PLG) has been widely utilized in multiple nanotechnology pharmaceutical applications. It has been approved by FDA [19,20]. Notably, few studies have investigated PVA/PLGA nano-formulations. For example, Panda et al. discussed the in vitro pharmaceutical characterization of PVA/PLGA nanofibres [21].
Nisin and nisin-loaded nanoparticles: a cytotoxicity investigation
Published in Drug Development and Industrial Pharmacy, 2022
Tanweer Haider, Vikas Pandey, Chittaranjan Behera, Pradeep Kumar, Prem N. Gupta, Vandana Soni
Nisin-loaded PLGA nanoparticles (NPN) were prepared by our previously optimized double emulsification solvent evaporation method [23]. Drug polymer ratio (1:2), PVA concentration (2.5% w/v), and in extraction media PVA (1.5% w/v) concentration were selected as optimized parameters for formulation. The drug powder (800 mg nisin powder) was weighed equivalent to 20 mg of nisin, dissolved in 1 ml of 0.02 N HCl, and filtered through a 0.45 µm filter (Millipore Millex-HN). The 40 mg PLGA was dissolved in 2 ml of DCM. The drug and polymer solution were mixed and added into 0.5 ml 2% v/v of span 80 and homogenized with a homogenizer (Pro scientific, Pro-200) at 16,000 rpm for 5 min. The W1/O emulsion was then added into the 5 ml of (2.5% w/v) PVA solution and homogenized at 16,000 rpm for 5 min. The resultant W1/O/W2 emulsion was obtained, which was then added dropwise via a needle (24 G) to (1.5% w/v) PVA extraction media (50 ml) with continuous stirring (Remi 1mLH stirrer, India). The polymeric dispersion was sonicated for 1 min by probe sonicator (Sonics Vibra Cell, model- CV18) at 130 watts and 20 kHz and stirred continuously with a magnetic stirrer at room temperature for 5 h. After that, nanoparticle suspension was centrifuged (Sigma 3-30 K centrifuge) at 18,000 rpm for 15 min at 4 °C to collect the nanoparticles. Subsequently, nanoparticles were washed thrice with purified water and lyophilized (VirTis, wizard 2.0 lyophilizer) and stored at 4 °C for further studies.
Recent advancements in cellulose-based biomaterials for management of infected wounds
Published in Expert Opinion on Drug Delivery, 2021
Munira Momin, Varsha Mishra, Sankalp Gharat, Abdelwahab Omri
Synthetic polymers are widely used as a material for wound dressing owing to their ease of manufacture and high availability. Advanced dressings are usually made of polymeric materials, which can provide a suitable wound environment and also serve as a carrier for drug delivery. Synthetic Polymers like poly(vinyl pyrrolidone), poly(lactide-co-glycolide), poly(hydroxyalkyl methacrylates), and poly(vinyl alcohol) are frequently employed in wound dressing [78]. In the case of synthetic polymers, poor biocompatibility and release of acidic degradation product (Dicarboxylic acid monomers) due to hydrolysis can be an issue. Moreover, natural polymers are similar to human ECM and are thus readily recognized and accepted by the body. They have many benefits, including natural abundance, apparent ease of isolation and scope for chemical alteration to suit technical needs [79]. These properties make natural polymers preferable over synthetic polymers.