Disposable Medical Devices Research Articles

Simultaneous determination of ethylene oxide, 2-chloroethanol and ethylene glycol residues in medical device products by gas chromatography

A gas chromatography-based method was developed for the simultaneous and rapid determination of ethylene oxide (EO), 2-chloroethanol (ECH), and ethylene glycol (EG) residues in medical devices after EO sterilization. A sample weighing 2.5 g was added with 5 mL of ethanol as the extraction medium, and the residual substances in the sample were extracted at 40 ℃ for 4 h. The samples were separated on a DB-WAX capillary column (30 m×0.53 mm×1.0 μm) and determined using a hydrogen flame ionization detector. The temperature was maintained at 40 ℃ for 5 min, increased to 120 ℃ at a rate of 40 ℃/min, held for 5 min, and then increased to 200 ℃ at a rate of 6 ℃/min, held for 2 min. The flow rate of the nitrogen gas was 3 mL/min. The split ratio was 5∶1. The inlet and detector temperatures were 200 and 300 ℃, respectively. The changes in the chromatographic peak areas over time (0.5-10 h) under different temperatures (20, 30, 40, and 50 ℃) were investigated, and the optimal extraction condition was determined to be 40 ℃ for 4 h. In the experiments, quantification was performed using an external standard method. EO, ECH, and EG exhibited good peak shapes and separation effects as well as good linearity within their respective ranges. The linear correlation coefficients for EO, ECH, and EG were greater than 0.99. The limits of detection (LODs) for EO, ECH, and EG were in the range of 0.10-0.40 μg/g, and the limits of quantification (LOQs) were in the range of 0.30-1.20 μg/g. The average recoveries under different spiked levels were in the range of 91.08%-116.08%, and the relative standard deviations (n=6) were in the range of 0.56%-8.45%. EO, ECH, and EG residues were found to exist at different levels in the medical devices tested. In particular, disposable infusion sets must be paid careful attention. ECH and EG were not detected in disposable sterile medical devices made of non-polyvinyl chloride materials, which may be due to the fact that the products themselves did not contain chloride ions, they were not exposed to chlorine-containing substances during their production, sterilization, storage, transportation, use, etc. This study established a method to detect EO residues in disposable medical devices, and has the advantages of simple operation, excellent specificity, accurate quantification, and good reproducibility. It can simultaneously detect three residual substances in medical devices while meeting the actual detection requirements for EO, ECH, and EG residues. The method can be used to scientifically and effectively evaluate the risk of EO residues in single-use medical devices sterilized with EO, and will be helpful for improving the quality of medical devices, ensuring the safety of device use, and providing a reference for regulatory supervision and testing.

The Healing and Aging-related Properties of Adipose Tissue Fragments Obtained through the Guided SEFFI Procedure’s Mechanical Fragmentation are Facilitated by the Exosomes Present in the Final Injection

The Injection of autologous Adipose-Derived Stem Cells (ADSCs) and Stromal Vascular Fraction (SVF) into dermal and subdermal layers can improve skin volume and rejuvenation. The SEFFI (Superficial Enhanced Fluid Fat Injection) technique, which involves minimal manipulation of autologous microfragmented adipose tissue, was utilized for harvesting and re-injection, using the SEFFILLER™ disposable medical device. Mechanical fragmentation of adipose tissue is a well-established surgical technique that stimulates tissue regeneration, filler, and biological activity. The study evaluated the biological properties (regenerative and anti-aging) of different harvest and processing fat graft methods among which the fragmented adipose tissue, specifically focusing on the presence of exosomes. Exosomes, nanometer-sized vesicles produced by cells for cellular communication, were found to contain miRNAs with anti-inflammatory, regenerative, and vascular content. The products’ contained exosomes were confirmed in the study through electron microscopy, Western Blotting, gene expression, and sequencing of miRNA content.

Microplastics released from disposable medical devices and their toxic responses in Caenorhabditis elegans.

Owing to accelerated urbanization and industrialization, many plastic products have been manufactured and discharged into the environment, causing environmental and public health problems. Plastics in environmental media are further degraded by prolonged exposure to light, heat, mechanical friction, and other factors to form new pollutants called microplastics (MPs). Medical plastics have become a crucial source of plastics in environmental media. However, the release profiles of MPs from medical plastics and their potential ecological and health risks remain unclear. We used optical photothermal infrared spectroscopy to explore the release profiles of eight typical disposable medical devices under high-temperature steam disinfection (HSD). We also evaluated the toxicity of disposable medical devices-derived MPs in Caenorhabditis elegans (C. elegans). Our results showed that the changes in the surface morphology and modification of the disposable medical devices were mainly associated with the material. Polypropylene (PP) and polystyrene (PS) materials exhibited high aging phenomena (e.g., bumps, depressions, bulges and cracks), and HSD broke their oxygen-containing functional groups and carbon chains. By contrast, minor changes in the chemical and physical properties were observed in the polyvinyl chloride (PVC)-prepared disposable medical devices under the same conditions. Further physicochemical characterization indicated that the amount of MPs released from PP-prepared disposable medical devices (P4: 1.27 ± 0.34 × 106) was greater than that from PVC-prepared disposable medical devices (P7: 1.08 ± 0.14 × 105). The particle size of the released MPs was the opposite, PVC-prepared disposable medical devices (P7: 11.45 ± 1.79 μm) > PP-prepared disposable medical devices (P4: 7.18 ± 0.52 μm). Toxicity assessment revealed that disposable medical devices-released MPs significantly increased germ cell apoptosisin C. elegans. Moreover, MPs from PP-prepared disposable medical devices disrupted the intestinal barrier of worms, decreasing their lifespan. Our findings provided novel information regarding the profiles and mechanisms of MP release from disposable medical devices and revealed their potential risks to ecological environment.

Validation of an indirect nonthermal plasma sterilization process for disposable medical devices packed in blisters and cartons

AbstractNowadays, the majority of the processes used to sterilize disposable medical devices have several drawbacks in terms of safety, energy consumption, and costs. In this work, a sterilization method based on an indirect nonthermal plasma treatment is presented. The main advantages of this method are low environmental impact, absence of harmful chemical compounds' storage, and backward compatibility relative to production, sterilization, and shipping chain. The sterilization of disposable devices, enclosed inside their protective packaging, is achieved by exploiting reactive species produced by a Dielectric Barrier Discharge plasma reactor. Various devices have been subjected to a 2‐h treatment, achieving complete sterilization based on USP and EU‐PHARMA protocols. Pretreatment of carton packaging has been necessary to guarantee a complete sterilization process.

FAKTOR-FAKTOR YANG BERPENGARUH TERHADAP PERILAKU PERAWAT DALAM PENERAPAN MANAJEMEN K3 DI RUANG RAWAT INAP

Occupational Diseases in hospitals can attack all workers,both medical, and non-medical people who have the risk of being exposed to hazardous biological materials,contact with disposable medical devices. Efforts to control, minimize the risk of work accidents, it is necessary to have good management of Hospital K3 management.The purpose of the study was to analyze the factors that influence the behavior of nurses in the application of K3 management in the inpatient ward of RSUD RM. Djoelham Binjai. research is explanatory research. The time of the study was from January to July 2022.The population of all nurses in the RSUD was 111 people. The sample was taken using purposive sampling as many as 53 people in all inpatient rooms inpatient care.Enabling factors(safety, security facilities,rules/policies do not affect thebehavior of nurses in the application of K3management.Reinforcing (supervision) factors affect the behavior of nurses in the application of K3 management. It is recommended that the hospital director be able tomake SOPpolicies and guidelines and sanctions regarding K3 supervision. For officers to supervise theimplementation of K3 management for nurses to behave safely when providing medical services and following policies and SOPs, given awards in order to cultivate OSH behavior in their respective work units.

Designing Take-Back for Single Use Medical Devices: The Case of ReturpenTM.

Focus on take-back of waste products is currently enjoying increased importance, as attention on environmental sustainability and circular economy grows. Single-Use or Disposable Medical Devices (SUDs), which in homecare settings often end up in landfills or incineration, are currently subject to attention, regarding the potential to slow the flow of waste and seek new value creation possibilities. Via a descriptive single-case study of the "ReturpenTM" initiative-a collaborative take-back initiative launched in three municipalities in Denmark-characteristics are elicited, of the planning, launch, and implementation, of the first 6-month pilot of the ReturpenTM initiative. ReturpenTM is a collaborative partnership of 15 public and private organizations and is adopting an end-to-end approach for its development and execution, including numerous professional workstreams. The pilot of the ReturpenTM achieved participation of 66 of the existing 73 pharmacies in 3 municipalities (90% participation rate), and an overall return rate of 13% for the used insulin pens, despite the limitations caused by the covid-19 pandemic. The return rates ranged from 10% to 15% in the 3 municipalities, and overall, the second quarter recovery (15%) was higher than the first quarter (11%). ReturpenTM demonstrates how a workstream-based approach can provide a practical framework for the development and implementation of SUD take-back in a homecare setting. The case describes how the pharmaceutical industry is taking proactive measures to contribute to a more circular economy for disposable medical devices, including the infrastructure and ecosystem necessary to ensure a closed-loop system for medical devices.

Overall Equipment Effectiveness (OEE) Analysis: A Case Study in the PVC Compound Industry

PT. Riken Indonesia is a company engaged in PVC Compound that is specially designed to meet the needs of industrial markets such as automotive construction, household electronic toys, and high quality disposable medical devices. The sample chosen was line 5 The purpose of this study was to analyze the value of OEE including the Availability, Performance rate and quality rate. The method used is Overall Equipment Effectiveness with analysis of Six Big Losses. For the analysis of six big losses to the OEE value, namely the setup & adjustment value of 86.27%, the breakdown value of 9.06%, the idling & minor stop value of 2.67%, and the defect value of 2.01%. Set up & adjustment are the main thing from the problem of six big losses, the biggest setup and adjustment is influenced by cleaning time of 61.61%, startup/shutdown of 37.65%, and adjustment of 0.74%. Based on the analysis, the Availability rate of 76.72%, a performance rate of 84.66%, and a quality rate of 99.89%. The OEE is consists of availability rate, performance rate and quality rate, the OEE value was 64.88%, which means it was below the standard value that is 85%. So it can be said that the engine performance in line 5 PT. Riken Indonesia has not been effective and requires maintenance or continuous improvement.

Atomic force microscopy and scanning electron microscopy as alternative methods of early identification of pathogens causing catheter-related bloodstream infections of patients in ICU

Abstract Introduction Vascular catheters are an indispensable element of the therapy of patients in intensive care. Their use is associated with the possibility of complications, including infectious. According to various sources, the incidence of catheter-related bloodstream infections (CRBSIs) ranges from 0.1 to 22.7 per 1,000 catheter days. Materials and Methods The central venous catheter tip culture samples were collected from 24 patients with suspected catheter-related bloodstream infection, from three intensive care units (ICUs). The results of microscopic examinations: atomic force microscope (AFM) and scanning electron microscope (SEM) were compared with the results of microbiological analysis of the central venous catheter tip and blood collected from the catheter. Results The microscopic examination and microbiological analysis of both the blood and central venous catheter samples confirmed the presence of microorganisms in 16 cases (double positive result). Our study was conducted in a short period of time (up to 6 hours) and it gave an initial answer to the question about the type of microorganisms colonising the central venous catheter. In one patient the infection was not caused by removal of the central venous catheter. However, not all results were fully consistent within the two diagnostic methods. The colonisation of the central venous catheter with Pseudomonas aeruginosa and Staphylococcus epidermidis was microbiologically confirmed, but it was not confirmed by the microscopic examination of the sample collected from patient No. 20. However, the examination enabled preliminary assessment of the microorganism colonising the catheter, which may have caused the blood infection. It cannot be ruled out that Pseudomonas aeruginosa bacilli were grown on the catheter that came into contact with blood from another source of infection, e.g. the respiratory, nervous or urinary systems. Information on the presence of cocci-shaped bacteria forming characteristic clusters or rods may enable initial diagnosis of catheter-related bloodstream infection if it is accompanied by typical clinical symptoms. Alternative diagnostics also provides valuable information on the presence of biofilm, which is a factor hindering the body’s response to infection and penetration of antibiotics. Conclusions Our pilot study presents new diagnostic possibilities of microscopic imaging with the atomic force microscope (AFM) and scanning electron microscope (SEM) to identify pathogens on routinely used disposable medical devices, such as the central venous catheter. On the other hand, this range of diagnostics reveals the potential to constantly improve medical materials which come into direct contact with patients’ tissues. It is important to create a database of microscopic images, which would be a repeatable diagnostic pattern and fully correlated with the results of microbiological analysis, because it would facilitate initial quick diagnosis of a potential CRBSI.

Features of medical waste management

The article argues that all medical waste requires a special approach as experience has shown that many substances used as safe pose a threat to human health and human life and cause irreparable damage to the environment. The expediency of reviewing certain categories of medical waste with their subsequent transfer to the category of household waste (office paper, office furniture, etc.) is specified. The need to pay more attention to waste in the cosmetics and perfume industry is emphasized as more and more pharmaceutical and chemical substances are used in this production. The article detects significant differences in some statistical indicators by year and the combination of medical and non-medical waste in one indicator, which indicates the imperfection of statistical accounting. The adequacy of medical waste management is revealed to depend on the standard of living in the country and the availability of effective public policy in this area, as well as the availability of natural resources in the required amount. The historical retrospective shows the changes in the attitude to disposable and reusable medical materials. The authors propose to use a table comparing the cost of disposal from different points of view, taking into account the necessary sanitary and hygienic requirements. The need to strengthen control over the rational use of disposable medical devices is emphasized, which in some cases makes it possible to significantly reduce the amount of waste and general medical expenses. A comparative analysis of the cost of medical waste disposal in the United States and Ukraine is conducted. The analysis shows that the United States has lower prices. Despite the rather carefully prescribed procedure for obtaining a license for activities in the field of medical waste management, the numerous abuses identified by inspections indicate the need to improve it.

Analysis of the effect of ionizing radiation on the properties of bulk nonwoven material

At the moment, there is a wide range of bulky nonwovens for various purposes on the market. One of the important areas of using such materials is healthcare. In particular, bulky nonwoven materials are intended for the manufacture of wound dressings, evacuation kits for newborns. Disposable medical devices of this kind are usually subjected to radiation sterilization. As is known from earlier studies, radiation sterilization significantly affects the performance of nonwovens. In this regard, for nonwoven materials for medical use, an important characteristic is the stability of indicators after exposure to radiation sterilization. As a result of the study of bulk nonwovens Holofiber ® after radiation radiation in the dose range from 20-60 kGy, there were no significant changes in operational performance. The stiffness increased by an average of 3-10%. The stiffness indicators after ionizing radiation according to GOST 24684 also meet the requirements. The value of electrification increased due to an increase in the static field under the action of ionizing radiation. It is worth noting that the values of electrification are within the norm established by GOST 32995. The breaking load varies from 1-5%. Thus, non-woven materials Holofiber ® PROFI, article P 35191, Holofiber ® SOFT, article P 5197, Holofiber ® SOFT, article P 5200 are recommended for the production of medical devices.

987 Braidlock - The Evolution of a Novel Drain Securing Device

Abstract Introduction The use of drains in Oral and Maxillofacial Surgery is widespread and the securing method using a silk suture laddering along the drain in a standard ‘roman sandal’ pattern is well established. Other methods include tie-lock with sutures and adhesive dressings. We describe the use of a braided device (Braidlock®) without using sutures, based on the concept of a Chinese finger trap, to secure the drain onto patients' skin using tissue adhesive. We report the evolutionary changes of Braidlock. Device Evolution Braidlock® is a Class I non-invasive disposable medical device which provides securement of lines, drains and catheters to a patient using tubing from 3.5Fr to 36Fr. The diameter of the Braidlock® expands when the device is compressed, similar to a ‘Chinese finger trap’. A line can then be inserted through the device and into the body. When decompressed, the Braidlock® squeezes the line tightly and securely. The initial Braidlock® device was hook & loop which required suturing to secure onto skin. Integrated adhesive is a recent invention. Advancement With advances in adhesive dressing and ultrasonic wielding between the plastic casing and adhesive pads, Braidlock® drain securing device appears to be a safe medical device that enables successful securement of drains. Braidlock® may represent a cost saving relative to the conventional suture pack for drain securement. Conclusions This new drain securing device offers a cost effective and reliable alternative to the standard suture fixation. This will eliminate the risk of sharps injury and allow shortening of the drain by ward staff with minimal training.

Environmental Waste Management of Disposable Surgical Coverage

The sustainable direction in the field of patient and medical staff health safety is the use of disposable medical devices, including disposable surgical masks, as recommended by the actual European standard. Disposable surgical coverage is the result of cooperation between medical professional workplaces worldwide and professionals in the area of nonwovens and lamination of material. Various variants were developed, tested and then rejected and then finally reach the material and variant composition. The use of disposable medical devices in healthcare is now a common practice, but also an environmental problem on a global scale. Despite the widespread adoption of this best practice, many healthcare facilities and patients still register resistance and scepticism against this form, actually also in connection with protection against COVID-19. The promoted opinion also by research-confirmed opinion is that the disposable form significantly reduces the amount of regulated medical waste that is generated during surgical procedures, subsequent sterilization and in the framework of protection against COVID-19. At the same time, logistical modeling of the best practice of environmental management in waste management remains a problem for the future. [ABSTRACT FROM AUTHOR] Copyright of Polish Journal of Environmental Studies is the property of Scientific Investigation Committee and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Fabrication of a Lateral Flow Assay for Rapid In-Field Detection of COVID-19 Antibodies Using Additive Manufacturing Printing Technologies.

The development of lateral flow immunoassay (LFIA) using three-dimensional (3D) printing and bioprinting technologies can enhance and accelerate the optimization process of the fabrication. Therefore, the main goal of this study is to investigate methods to speed up the developing process of a LFIA as a tool for community screening. To achieve this goal, an in-house developed robotic arm and microfluidic pumps were used to print the proteins during the development of the test. 3D printing technologies were used to design and print the housing unit for the testing strip. The proposed design was made by taking into consideration the environmental impact of this disposable medical device.

Transforming The Medical Device Industry: Road Map To A Circular Economy.

A circular economy involves maintaining manufactured products in circulation, distributing resource and environmental costs over time and with repeated use. In a linear supply chain, manufactured products are used once and discarded. In high-income nations, health care systems increasingly rely on linear supply chains composed of single-use disposable medical devices. This has resulted in increased health care expenditures and health care-generated waste and pollution, with associated public health damage. It has also caused the supply chain to be vulnerable to disruption and demand fluctuations. Transformation of the medical device industry to a more circular economy would advance the goal of providing increasingly complex care in a low-emissions future. Barriers to circularity include perceptions regarding infection prevention, behaviors of device consumers and manufacturers, and regulatory structures that encourage the proliferation of disposable medical devices. Complementary policy- and market-driven solutions are needed to encourage systemic transformation.

Crystallization and Stability of Flexible P-Type Semiconductors and Their Thin Film Transistor Application

In recent years, electronic devices that require superior mechanical flexibility have been extremely sought for potential applications in next-generation displays, sensors, bio-implantable and disposable medical devices. Polymeric materials, of which the flexibility far exceeds that of conventional brittle inorganic counterparts, are widely considered for various flexible devices due to their excellent stretchable, foldable and bendable characteristics.Oxidative chemical vapor deposition (oCVD) is an emerging technique that provides not only a capability to process mechanically flexible polymeric films but also strategies to address current challenges claimed in typical solution-based polymer processing1-2. The oCVD technique allows for greater uniformity, excellent conformality, enhanced performance (e.g., conductivity) and an ability of large area polymer processing that are limited in conventional solution-processed polymers3-4.Crystallization and air stability of organic materials have been issues that have to be mitigated to warrant high performance and sustainable device applications. The oCVD technique, in addition to the advantages described above, could also address the issues of crystallization and air stability to enhance the carrier transport and overall conductivity, and to secure sustainability. We recently found that an in-situ oCVD capability of substrate heating during depositions resulted in an substantial increase in ordered structures in conjugated polymers, leading to enhanced crystallization of the resulting oCVD polymers5. Consequently, the enhancement of the carrier transport and conductivity was obtained due to the increase in favorable conduction paths in the crystalline phase. Further, the vapor phase processing of oCVD may be of crucial relevance to achieve air stability since oCVD does not require any monomer solubility in specific solvents and, therefore, is able to polymerize insoluble materials6 that are not available for conventional solution processing techniques such as spin-coating or dip-casting. The reactivity of insoluble monomers is quite limited due to their rigid backbone structures; however, this limited reactivity is the key to achieve air stability since the reactions between insoluble materials and water (H2O)/oxygen, which are the main origins to cause instabilities of organic materials in air, are significantly prohibited.In this presentation, we report our recent findings of enhanced crystallization and air-stability of oCVD polymers. Particularly, the structure, chemical and electrical properties of two oCVD polymers, poly(3,4-ethylenedioxythiophene) (i.e., PEDOT) and unsubstituted polythiophene, will be compared with focuses on the crystalline state, dope-ability and air-stability. Further, thin film transistors (TFTs) that employ the two oCVD polymers as TFT channel are presented and the device performance of output and transfer characteristics will be compared with focuses on the carrier mobility and on/off switching properties. Acknowledgement: This work was supported by Purdue University and partly by an NSF grant, Award No. ECCS-193108. References Lock, J. P.; Im, S. G.; Gleason, K. K., Oxidative chemical vapor deposition of electrically conducting poly(3,4-ethylenedioxythiophene) films. Macromolecules 2006, 39 (16), 5326-5329.Im, S. G.; Gleason, K. K., Systematic control of the electrical conductivity of poly(3,4-ethylenedioxythiophene) via oxidative chemical vapor deposition. Macromolecules 2007, 40 (18), 6552-6556.Coclite, A. M.; Howden, R. M.; Borrelli, D. C.; Petruczok, C. D.; Yang, R.; Yaguee, J. L.; Ugur, A.; Chen, N.; Lee, S.; Jo, W. J.; Liu, A.; Wang, X.; Gleason, K. K., 25th Anniversary Article: CVD Polymers: A New Paradigm for Surface Modification and Device Fabrication. Adv. Mater. 2013, 25 (38), 5392-5422.Kovacik, P.; Hierro, G. d.; Livernois, W.; Gleason, K. K., Scale-up of oCVD: large-area conductive polymer thin films for next-generation electronics. Materials Horizons 2015, 2 (2), 221-227.Wang, X.; Zhang, X.; Sun, L.; Lee, D.; Lee, S.; Wang, M.; Zhao, J.; Shao-Horn, Y.; Dincă, M.; Palacios, T.; Gleason, K. K., High electrical conductivity and carrier mobility in oCVD PEDOT thin films by engineered crystallization and acid treatment. Science Advances 2018, 4 (9), eaat5780.Borrelli, D. C.; Lee, S.; Gleason, K. K., Optoelectronic properties of polythiophene thin films and organic TFTs fabricated by oxidative chemical vapor deposition. Journal of Materials Chemistry C 2014, 2 (35), 7223-7231. Figure 1

Highly improved aqueous lubrication of polymer surface by noncovalently bonding hyaluronic acid-based hydration layer for endotracheal intubation

Hydration lubrication is the key responsible for the exceptionally low boundary friction between biosurfaces. However, it is a challenge to settle a hydration layer on a polymer surface via a noncovalent manner. Herein, we develop a highly lubricated coating absorbed onto the polymer surface via intermolecular association of hyaluronic acid (HA)-based micelles. A poly(ethylene oxide)-b-poly(propylene oxide)-b-poly(ethylene oxide) triblock copolymer (Pluronic, F127) is recruited to complex with HA and further self-assembled to form a thick micelle layer. High water-retaining capacity of the HA/F127 coating enables the decorated surface with excellent hydrophilicity and boundary lubrication, where the coefficient of friction in aqueous media is reduced by 60% compared with the bare polymer surface. The HA/F127 coating suppresses nonspecific protein adsorption and exhibits good biocompatibility. More remarkably, an in vivo cynomolgus monkey model, demonstrates the utility of the HA/F127 coating in alleviating or preventing complications of endotracheal intubation, such as foreign irritation, airway mucosal damage, and inflammatory response. This cost-effective and scalable approach is suitable to manufacture interventional devices especially disposable medical devices with highly lubricated surface.

Predicting Production Cycle Time in a Real Disposable Medical Device Manufacturing System Using Semi-Supervised Deep Learning

Manufacturing lot cycle time is the period required by a manufacturer for completion of a production process. It is an essential factor for determining the success of most manufacturing organizations, yet most research is based on studies made almost exclusively in the semiconductor industry and does not attempt to utilize the complete potential of recent breakthroughs in computational learning. Using real data collected from a medical device manufacturing company, this paper demonstrates the applicability of a semi-supervised deep learning framework for highly accurate cycle time prediction, using stacked Denoising Autoencoders to form fully connected deep neural networks and Convolutional Neural Network models. The proposed strategies for cycle time prediction can have a significant impact on product design decision optimization within the system which, in turn, facilitates reduction of costs, energy use, and the overall environmental impact.

(Invited) Crystallization and Stability of Flexible P-Type Semiconductors and Their Thin Film Transistor Application

In recent years, electronic devices that require superior mechanical flexibility have been extremely sought for potential applications in next-generation displays, sensors, bio-implantable and disposable medical devices. Polymeric materials, of which the flexibility far exceeds that of conventional brittle inorganic counterparts, are widely considered for various flexible devices due to their excellent stretchable, foldable and bendable characteristics.Oxidative chemical vapor deposition (oCVD) is an emerging technique that provides not only a capability to process mechanically flexible polymeric films but also strategies to address current challenges claimed in typical solution-based polymer processing1-2. The oCVD technique allows for greater uniformity, excellent conformality, enhanced performance (e.g., conductivity) and an ability of large area polymer processing that are limited in conventional solution-processed polymers3-4.Crystallization and air stability of organic materials have been issues that have to be mitigated to warrant high performance and sustainable device applications. The oCVD technique, in addition to the advantages described above, could also address the issues of crystallization and air stability to enhance the carrier transport and overall conductivity, and to secure sustainability. We recently found that an in-situ oCVD capability of substrate heating during depositions resulted in an substantial increase in ordered structures in conjugated polymers, leading to enhanced crystallization of the resulting oCVD polymers5. Consequently, the enhancement of the carrier transport and conductivity was obtained due to the increase in favorable conduction paths in the crystalline phase. Further, the vapor phase processing of oCVD may be of crucial relevance to achieve air stability since oCVD does not require any monomer solubility in specific solvents and, therefore, is able to polymerize insoluble materials6 that are not available for conventional solution processing techniques such as spin-coating or dip-casting. The reactivity of insoluble monomers is quite limited due to their rigid backbone structures; however, this limited reactivity is the key to achieve air stability since the reactions between insoluble materials and water (H2O)/oxygen, which are the main origins to cause instabilities of organic materials in air, are significantly prohibited.In this presentation, we report our recent findings of enhanced crystallization and air-stability of oCVD polymers. Particularly, the structure, chemical and electrical properties of two oCVD polymers, poly(3,4-ethylenedioxythiophene) (i.e., PEDOT) and unsubstituted polythiophene, will be compared with focuses on the crystalline state, dope-ability and air-stability. Further, thin film transistors (TFTs) that employ the two oCVD polymers as TFT channel are presented and the device performance of output and transfer characteristics will be compared with focuses on the carrier mobility and on/off switching properties. Acknowledgement: This work was supported by Purdue University and partly by an NSF grant, Award No. ECCS-193108.

Concentration of N-Nitrosamines in condoms purchased in Korea

TPS 624: Exposures to pops, voc and other chemicals, Johan Friso Foyer, Floor 1, August 26, 2019, 3:00 PM - 4:30 PM N-Nitrosamines are the nitroso-compounds which are produced by nitrosation reactions of the secondary amine and nitrite. N-Nitrosamine has been found to be produced through the vulcanization process during the production of rubber products. Recently, nitrosamines have been detected in rubber products and become a major topic. Condoms are disposable medical devices, so safety is important because they come into direct contact with the skin and mucous membranes. In this study, we modified an analysis of nitrosamines in the condoms of 2016, which was created by applying the ISO 29941 method. The samples were eluted by distilled water, and target compounds were extracted by liquid-liquid extraction with dichloromethane. And then after concentrated, and quantitatively analyzed by LC-MS/MS. Validation was performed prior to analyzing the samples. The accuracies of the analytical method were ranged from 87.4 to 112.2%, precisions were lower than 10.7%, and the detection limits were from 0.16 (NDPA) to 0.81 (NDELA) ng/mL. In this study, 190 condoms distributed in Korea were analyzed. Interestingly, different types of nitrosamines were found in different samples of companies. NDBA was detected in all samples. The concentrations of nitrosamine in the condoms were NDMA: ND~8.1ng/g, NDEA: ND~144.2ng/g, NDBA: ND~161.5ng/g NDELA: ND~17.9ng/g. Of the 190 samples, NDMA were detected from 6 case, NDEA from 88 cases, NDBA from 184 cases and NDELA from 11 cases. There were no significant differences in the concentrations of the samples in the same LOT number, but the sample concentrations were different when the LOT numbers were different. The concentration was lowered as it was washed several times. Nitrosamines are detected in condoms distributed in Korea, and various kinds of vulcanizing agents are used by companies, so that various types of nitrosamines are detected. Because nitrosamines are highly hydrophilic, fewer nitrosamines were detected when the condom was washed multiple times.

Effect of different sterilization methods on the properties of commercial biodegradable polyesters for single-use, disposable medical devices.

The increasing employment of non-degradable polymers based single-use, disposable medical devices have led to huge environmental pressure. Replacement of non-degradable polymers with biodegradable alternatives could be one solution. Since terminal sterilization is a necessary procedure for medical devices to eliminate infections, in this paper, the modifications of sterilization on the transparency, yellow index, dimensional stability and mechanical properties of commercial biodegradable poly(lactic acid) (PLA), poly(butylenes adipate-co-terephthalate) (PBAT) and their blends were investigated. The samples were prepared by compression molding and exposed to four sterilization treatments including ethylene oxide gas (EtO), saturated steam (SS), electron beam (EB), and hydrogen peroxide gas plasma (HPGP). It is concluded that EB can be applied for the sterilization of all the materials investigated, while SS and EtO are not recommended for PLA, and HPGP is not for PBAT and PLA/PBAT blends. This study demonstrates that, when a suitable sterilization process is chosen, PLA has potential to be used for transparent medical devices such as the barrel of syringes or microfluidic chips, while PBAT and PLA/PBAT blends for other non-transparent medical packaging applications.