Evaluation of a Photo‐Sterilizable Polyvinyl Chloride Embedded With Methylene Blue for the Inactivation of Candida albicans: A Study on Efficacy, Reusability, and Storage

Impact of cleaning and disinfection on the non-culturable and culturable bacterial loads of food-contact surfaces at a beef processing plant

The adsorption of albumin, gamma-globulin, and fibrinogen was measured on three ex vivo polymeric shunt surfaces [polyvinyl chloride (PVC), Silastic, and segmented polyether urethane (Biomer)] exposed to flowing heparinized, canine blood in vivo. Small amounts of radiolabeled proteins were infused into anesthetized mongrel dogs and the deposition of radioactivity on the walls of femoral arteriovenous shunts was followed with time for two hours following initial blood-polymer contact. Previously, transient in vivo platelet and fibrin deposition onto PVC, Silastic, and Biomer was measured by a similar technique in the absence of anticoagulant. A time-dependent phase of thrombus deposition followed by thromboembolism was observed on the PVC and Silastic shunt surfaces but not on the Biomer surface. In the studies reported here on PVC and Silastic, fibrinogen adsorption was found to predominate initially, though it subsequently desorbed somewhat and was replaced by albumin and gamma-globulin. On Biomer, the adsorption of all three proteins increased with time following initial blood contact and fibrinogen was less prominent initially. The PVC surface was found to become passivated with respect to further thrombogenesis after 60-min exposure to flowing blood, at which time a higher fraction of albumin was present on the surface compared to that at earlier blood contact times. These results indicate that rearrangement of adsorbed protein species occurs with time on polymer surfaces exposed to flowing blood in vivo. Early and predominant fibrinogen adsorption appears to be an important factor in the thrombogenic and embolic events observed on the PVC and Silastic shunt surfaces in vivo.

The TiO(2) film was coated on poly vinyl chloride (PVC) surface by dip-coating process from TiO(2)-PVC-THF suspension. The morphology and crystal structure of the as-synthesized samples were characterized by SEM and XRD. The photocatalytic properties were measured by the photodegradation reaction of RhB and the anti-adhesion and anti-bacteria for Escherichia coli. The results show that the resultant TiO(2) film is well-conglutinated on PVC surface and has the same crystal structure as the original TiO(2) powder. The TiO(2)/PVC shows excellent photocatalytic activity for the degradation of aqueous RhB and the activity increases with increasing reaction time and tends toward stable after accumulative illumination for 11.5 h. The TiO(2) film shows good bacterial anti-adhesion activity following photo-activation and sterilization property under UV irradiation. The E. coli can be killed completely after UV irradiation for 1.5 h.

Background and objectives: Medical devices such as catheters are used on a large scale to treat heart and cardiovascular diseases. Unfortunately, they present some important drawbacks (structure failure, calcifications, infections, thrombosis, etc.), with the main side effects occurring due to adhesion and proliferation of bacteria and living cells on the surface of the implanted devices. The aim of this work is to modify the surface of polyvinyl chloride (PVC), an affordable biocompatible material, in order to reduce these aforementioned side effects. Materials and Methods: The surface of PVC was modified by depositing a thin layer also of PVC that incorporates an active substance, dicoumarol (a well-known anticoagulant), by spin coating process. The modified surfaces were analyzed by Fourier-transform infrared (FT-IR) microscopy, Fourier-transform infrared (FT-IR) spectroscopy, Ultraviolet-visible spectroscopy (UV-VIS), and Scanning electron microscopy (SEM) in order to determine the surface morphology and behavior. The samples were tested for Gram-positive (S. aureus ATCC 25923) and Gram-negative (P. aeruginosa ATCC 27853) standard strains from American Type Culture Collection (ATCC). Results: The material obtained had a smooth surface with a uniform distribution of dicoumarol, which is released depending on the deposition parameters. The concentration of dicoumarol at the surface of the material and also the release rate is important for the applications for which the surface modification was designed. PVC modified using the proposed method showed a good ability to prevent salt deposition and decreased the protein adhesion, and the resistance to bacterial adherence was improved compared with standard PVC.

Summary form only given. There is an increasing interest on the development of antibacterial medical polymers in the biomedical industry. Most of antibacterial polymers are made by addition of antibacterial materials generally containing Ag+, but inside humans, these antibacterial polymers may pose health hazards and so alternative polymeric materials must be developed. In this work, plasma immersion ion implantation (PIII) is used to modify the surface of medical PVC (poly vinyl chloride) by DP-300 to improve its antibacterial performance. The surface is first activated by O2 plasma to produce more hydrophilic groups so that DP-300 can be coated well on the surface. Subsequently, Ar plasma-treatment is conducted under optimal conditions to render its surface antibacterial. The modified surface is characterized by XPS, SEM, ATR-FTIR, AFM and contact angle measurements. The antibacterial performance is tested utilizing the method of plate counting of Micrococcus luteus (gram positive) and Escherichia coli (gram negative). The antibacterial performance with time and antibacterial mechanism of PVC are also discussed. Experimental results show that the plasma-treated surface exhibits good antibacterial performance while the favorable bulk properties of PVC are retained

Flotation separation of hazardous polyvinyl chloride towards source control of microplastics based on selective hydrophilization of plasticizer-doping surfaces

Antifouling surfaces are specifically crucial to cardiovascular applications. In this study, a polyvinylchloride (PVC) surface was modified by coating a biocompatible and hydrophilic polymer by a mild coating technique. The PVC surface was first activated and then functionalized, followed by coating with the polymer. Results show that the coated hydrophilic polymer significantly reduced 3T3 fibroblast cell adhesion as well as bacteria adhesion. The 3T3 cell adhesion to the polymer-coated surface was reduced to 52–66% as compared to the original PVC surface. Bacterial adhesion to the polymer-coated surface was reduced to 61–80% for Pseudomonas aeruginosa, 65–81% for Staphylococcus aureus, and 73–85% for Escherichia coli, as compared to the original PVC surface. It appears that this novel polymer-coated PVC surface has an antifouling property.

This paper presents a one-step selective separation of polyvinyl chloride (PVC) from PVC/PET mixture based on hydrophilicity building on the PVC surface using H2O2/ultrasonication. After the combined treatment, the decrease of PVC contact angle (from 87.2° to 71.5°) is consistent with the increase in hydrophilic functional groups that is evidenced by Fourier transform infrared and X-ray photoelectron spectroscopy results on the PVC surface. The H2O2/ultrasonic treatment generates oxidizing agent and increases hydrophilicity on the PVC surface, which allows to selectively separate the treated PVC by its submerging on the reactor bottom. Meanwhile, the treated PET is easily floated off because it is not affected by the combined treatment and still maintains the hydrophobic surface. The combined treatment of H2O2 and ultrasonic irrigation obtains 100% purity and recovery of the PVC separation under the optimum conditions. The optimized separation conditions are H2O2 concentration 3%, ultrasonic irrigation time 30 min and temperature 30 °C, floating agent concentration 0.4 mg/L and intermittent mixing at 50 rpm. Reusing of H2O2 is also feasible to save cost and environmental benefits. The combination of ultrasonication and H2O2 is an effective and inexpensive method for PVC separation to improve plastic recycling quality.

Sustainable hydrophilization to separate hazardous chlorine PVC from plastic wastes using H2O2/ultrasonic irrigation

Flotation separation of poly (ethylene terephthalate and vinyl chloride) mixtures based on clean corona modification: Optimization using response surface methodology.

The impact of UV/ozone treatment on the wettability and adhesion of ethylene propylene diene methylene (EPDM) rubber, polyvinyl chloride (PVC), and acrylonitrile butadiene styrene (ABS) was investigated using contact angle measurements, OWRK surface free energy model, standardized adhesion tests, and spectroscopic and microscopic observations. It is found that UV/ozone treatment enhances the wettability of the examined polymers. Also, it considerably improved the adhesion strength of PVC and ABS samples, and shifted their failure modes from adhesive to cohesive. FTIR-ATR characterization showed insignificant changes in the chemical structures of the studied materials. However, SEM observation showed newly-created wrinkles and micro-holes on treated PVC surfaces, and micropores on ABS surfaces. These UV-induced morphological changes on PVC and ABS surfaces increased the surface area which can promote the mechanical interlocking with the adhesive. This explains the improvement of their adhesion strength. Implications of the current study for the processing of strongly bonded polymeric joints are discussed.

This paper presents an experimental and theoretical study of aqueous diesel contamination and decontamination of a polyvinyl chloride (PVC) surface and an iron (Fe) surface. A test apparatus designed for the purpose of studying adsorption of diesel from a flowing dilute diesel/water mixture was used to measure the mass of diesel adsorbed per unit surface area (the excess surface density) and the bulk concentration of the diesel in the flow using a fluorescence based measurement technique. Both bulk composition and the excess surface density measurements were achieved via a traverse of the fluorescent measurement probe perpendicular to the test surface. The diesel adsorption to each test surface was examined for three different Reynolds numbers between zero and 7000. Measurements for a given condition were made over a period of approximately 200 h for a diesel mass fraction of approximately 0.15 % in tap water. For a Reynolds number of approximately 7000, the largest excess layer thickness was approximately 4.4 μm, which was measured on a PVC surface. Averaging over all contaminating flow rates and exposure times, the excess layer thickness on the PVC surface was approximately 2.0 μm. Reynolds number had little or no effect on the accumulation of diesel on an iron surface, which was approximately 0.71 μm. The adsorbed diesel on the PVC and iron surfaces was removed by flushing with tap water. Models to predict excess layer thickness during flushing and contamination were developed. The models predict flushing times to within 7 h and predict the influence of pipe surface on contamination level.

Superhydrophobic, nanotextured polyvinyl chloride films for delaying Pseudomonas aeruginosa attachment to intubation tubes and medical plastics

The effect of CD47 modified polymer surfaces on inflammatory cell attachment and activation

Evidence of free radical generation from the interaction of polyethylene glycol with PVC medical tubing