Influence of Washing and Sterilization on Properties of Polyurethane Coated Fabrics Used in Surgery and for Wrapping Sterile Items

Effect of Sterilization Methods on Chemical and Physical-Mechanical Properties of Cotton Compresses

The aim of this work was to determine the changes in the chemical and physical-mechanical properties of gauze compresses under the influence of various sterilizations. Gauze compresses are made of cotton; therefore, all methods used focused on cotton. The methods used to test possible damage to cotton materials (pH value (pH paper, KI starch paper), yellowing test, Fehling reaction, reaction to the formation of Turnbull blue (Berlin blue), microscopic staining with methylene blue and swelling reaction with Na-zincate) did not show that the sterilizations affected the cotton compresses. The morphological characteristics were examined with a scanning electron microscope (SEM). The SEM images showed that there were no morphological changes in the cotton fibers. FTIR-ATR spectroscopy revealed that the sterilization processes did not alter the characteristic bands of the cotton. The length of the macromolecules was increased (DP), showing that the sterilization processes had affected the cotton. The results of the wet strength test followed. The samples showed values below 100%, with the exception of two samples. It is known from theory that the relative wet strength is less than 100% when the material is damaged. The t-test performed on the strength results showed that the p-value was greater than 0.05 for all samples tested, with the exception of one sample. The degree of swelling capacity was determined, with non-sterilized samples having the highest capacity, followed by samples sterilized with ethylene oxide and then samples sterilized by steam sterilization. The results obtained are a contribution to the innovation of the topic of this work and a scientific confirmation for manufacturers and anyone interested in the influence of the sterilization process on natural fibers (cotton).

Effect of far-infrared radiation on inhibition of colonies on packaging during storage of sterilised surgical instruments

The sterilisation of surgical instruments is a major factor in infection control in the operating room (OR). All items used in the OR must be sterile for patient safety. Therefore, the present study evaluated the effect of far-infrared radiation (FIR) on the inhibition of colonies on packaging surface during the long-term storage of sterilised surgical instruments. From September 2021 to July 2022, 68.2% of 85 packages without FIR treatment showed microbial growth after incubation at 35 °C for 30 days and at room temperature for 5 days. A total of 34 bacterial species were identified, with the number of colonies increasing over time. In total, 130 colony-forming units were observed. The main microorganisms detected were Staphylococcus spp. (35%) and Bacillus spp. (21%) , Kocuria marina and Lactobacillus spp. (14%), and mould (5%). No colonies were found in 72 packages treated with FIR in the OR. Even after sterilisation, microbial growth can occur due to movement of the packages by staff, sweeping of floors, lack of high-efficiency particulate air filtration, high humidity, and inadequate hand hygiene. Thus, safe and simple far-infrared devices that allow continuous disinfection for storage spaces, as well as temperature and humidity control, help to reduce microorganisms in the OR.

The Electrical Conductivity and Mechanical Properties of Monolayer and Multilayer Nanofibre Membranes from Different Fillers: Calculated Based on Parallel Circuit

Advanced research on improving the performance of conductive polymer composites is essential to exploring their potential in various applications. Thus, in this study, the electrical conductivity of multilayer nanofibre membranes composed of polyvinyl alcohol (PVA) with different electroconductive fillers content including zinc oxide (ZnO), multiwalled carbon nanotubes (MWNTs), and Ferro ferric oxide (Fe₃O₄), were produced via electrospinning. The tensile property and electrical conductivity of monolayer membranes were explored. The results showed that PVA with 2 wt.% MWNTs nanofibre membrane has the best conductivity (1.0 × 10^-5 S/cm) and tensile strength (29.36 MPa) compared with other fillers. Meanwhile, the combination of multilayer membrane ZnO/Fe₃O₄/Fe₃O₄/MWNTs/ZnO showed the highest conductivity (1.39 × 10^-5 S/cm). The parallel circuit and calculation of parallel resistance were attempted to demonstrate the conductive mechanism of multilayer membranes, which can predict the conductivity of other multilayer films. The production of multilayer composites that enhance electrical conductivity and improve conductive predictions was successfully explored.

Application of 3D-Woven Fabrics for Packaging Materials for Terminally Sterilized Medical Devices

This research aimed to test a newly developed 3D fabric for use in a hospital sterilization unit as a packaging material. Two basic properties were tested: the efficiency of the microbial barrier, and the bursting strength of the woven fabric, determined with a steel ball. Material deformations caused by bursting are common in medical sterilization, as a consequence of the packaging of the medical tools needed in surgery. Six 3D-fabric samples were woven from the same warp, with three weft densities and in two different weaves. The weaving conditions and other construction characteristics of the fabrics were the same. To determine the effectiveness of the microbial barrier, bacterial endospores of an apathogenic species of the genus Bacillus, Geobacillus stearothermophilus and Bacillus atrophaeus, were used. Mechanical testing of the 3D-woven fabric, i.e., the bursting strength of the fabric using a steel ball, was carried out according to the standard method. The results showed the exceptional puncture strength of the woven fabrics and their formation of an effective microbial barrier, i.e., complete impermeability to microorganisms in five samples, which is the main condition for possible use as a packaging material in medical sterilization. Sample 3tp did not provide an effective microbial barrier and did not meet the basic requirements for use in medical sterilization.

Special Features of Polyester-Based Materials for Medical Applications

This article presents current possibilities of using polyester-based materials in hard and soft tissue engineering, wound dressings, surgical implants, vascular reconstructive surgery, ophthalmology, and other medical applications. The review summarizes the recent literature on the key features of processing methods and potential suitable combinations of polyester-based materials with improved physicochemical and biological properties that meet the specific requirements for selected medical fields. The polyester materials used in multiresistant infection prevention, including during the COVID-19 pandemic, as well as aspects covering environmental concerns, current risks and limitations, and potential future directions are also addressed. Depending on the different features of polyester types, as well as their specific medical applications, it can be generally estimated that 25-50% polyesters are used in the medical field, while an increase of at least 20% has been achieved since the COVID-19 pandemic started. The remaining percentage is provided by other types of natural or synthetic polymers; i.e., 25% polyolefins in personal protection equipment (PPE).