Sterile Filtration.

The great majority of sterile products commercially available as well as prepared in compounding pharmacies are sterilized by sterile filtration during aseptic processing. This brief and basic review will highlight the nature, action, and use of sterilizing filters. Special emphasis is given to how filters are validated in producing a sterile filtrate while being compatible with the filtered solution, as well as how filters are integrity tested during aseptic processing.

Infant Oral Candidiasis and Bottle Cleaning Methods: A Descriptive Study.

As manufacturers produce bottles with additional parts, such as an anticolic straw, cleaning time increases. Increased cleaning time potentially decreases cleaning effectiveness and, thus, increases the chance for thrush. This study explored the relationship between the number of bottle parts and cleaning methods for bottle-fed-only infants (<13 months) presenting with oral candidiasis. After obtaining demographic information on eligible infants (via parental consent) from the chart, caregivers of 60 infants verbally completed a questionnaire. The questionnaire elicited information about the preferred bottle for feeding, number of parts, washing frequency, washing method, drying method, sterilization frequency, and sterilization method. The χ2 test, and Fisher's exact test when necessary, was performed to examine the relationship between each reported cleaning method (washing, drying, and sterilization) compared with the number of bottle parts (≤3 or ≥4). The number of bottle parts showed no association with bottle cleaning methods (p > .05). Although there were no statistically significant relationships, trends did present that warrant investigation. Future studies to confirm recommended practices for cleaning methods and identify those at risk from demographic data could positively affect the health of bottle-fed infants by reducing the occurrence of thrush.

A new protocol for renal collecting system sterilization with antibiotic irrigation during lithotripsy in retrograde intrarenal surgery: a prospective, comparative study.

PURPOSE: To present a new protocol using antibiotic irrigation during lithotripsy in retrograde intrarenal surgery (RIRS) to provide sterility of the renal collecting system. METHODS: This prospective study included 102 patients who underwent RIRS between January 2022 and August 2023. The patients were examined in two groups as those who received antibiotic irrigation (n:51) and standard irrigation (n:51). In the antibiotic irrigation group, 80 mg of gentamicin was dissolved in normal saline in a 3 L irrigation pouch to obtain a 26.7 mg/L concentration. In the standard irrigation group, normal saline was used. Preoperative information, including age, sex, body mass index (BMI), ASA score, stone side, volume, and density, and the Seoul National University Renal Stone Complexity (S-ReSC) score. The groups were compared with respect to postoperative fever (> 38 °C), urinary tract infection (UTI), systemic inflammatory response syndrome (SIRS), infectious complications such as sepsis, and stone-free rate. RESULTS: No statistically significant difference was determined between the groups with respect to age, sex, BMI, ASA score, stone side, volume and density, and S-ReSC score (p > 0.05 for all). Statistically significant differences were determined between the groups with respect to postoperative fever (p = 0.05), SIRS (p = 0.05), and hospital length of stay (p = 0.05). Sepsis was observed in one patient in the standard irrigation group and in none of the antibiotic irrigation group. CONCLUSION: The reliability, efficacy, and utility of antibiotic irrigation during lithotripsy in RIRS were presented in this study as a new protocol for sterilization of the renal collecting system which will be able to reduce infectious complications.

A Novel Technique of Aseptic Manufacture of Autologous Serum Eye Drops (ASEDs) and Sterility Analysis of the Bottled Ophtioles.

PURPOSE: To introduce a novel technique of the aseptic manufacture of autologous serum eye drops (ASEDs) with a prefiltered closed system and to analyze the sterility of the produced ophtioles between 2018 and 2022. METHODS: This is a prospective single-center study conducted at the Department of Ophthalmology at a Swiss University Hospital between 2018 and 2022. For regulatory reasons, closed systems for manufacturing ASEDs are strongly recommended. We attached an upstream sterile filter (Sterivex PES0.22 µm Burlington, USA) to a commercially available closed system (COL System Modena, Italy) for manufacturing ASEDs. The goal of this novel approach was to reduce the microbiological contamination of the donated autologous blood. Using the presented manufacturing method, we are able to produce, on average, 56 ophtioles per batch, containing either 1.45 mL or 2.5 mL of autologous serum per ophtiole. For each batch of ASEDs, we performed a microbiological analysis by automated blood culture testing (BACTEC). This system examines the presence of bacteria and fungi. RESULTS: We analyzed all manufactured batches between 2018 and 2022. None of the 2297 batches and the resulting 129 060 ophtioles showed bacterial or mycotic contamination. During the analyzed period, two batches were discarded: one due to fibrin-lipid aggregations, further microbiological and histological work-up excluded any contamination; another due to false-positive HIV in serological testing. Overall, the contamination rate was 0%, and the batch discharge rate was 0.09%. CONCLUSIONS: The combination of upstream sterile filtration with a commercial closed system for manufacturing ASEDs proved to be effective in ensuring sterility without any contamination over the past 4 years. This is becoming crucial, as the demand for autologous blood products for treating ocular surface disorders, such as refractory dry eyes or nonhealing defects of the corneal epithelium, is on the rise.

Analysis of Wet Pack Incidence in Steam Sterilization: A Study in a Chinese Medical Center.

BACKGROUND Central sterile supply departments (CSSDs) play a vital role in hospital infection control. We investigate the factors associated with wet pack occurrence after steam sterilization. MATERIAL AND METHODS We designed a log sheet to record information concerning sterilized packs. The data included the type of sterilized pack; outside weather (sunny, overcast, or rainy); the item in the sterilized pack; packaging material; whether the item had been packaged in compliance with guidelines; whether the pack had been laid flat, upright, or leaning at an acute angle; which sterilizer was used for sterilization of the pack; whether the pack had been placed on the top or bottom shelf inside the sterilizer chamber; whether the pack had been loaded in compliance with guidelines; the drying time following sterilization; and cooling time after sterilization. The sterilized packs in our study were selected from all of the packs that were sterilized in the CSSD of the authors' institution during June to December 2021. RESULTS Factors associated with wet pack occurrence after steam sterilization include: outside weather on the day of sterilization; the item in the sterilized pack; packaging material; whether the item had been packaged in compliance with guidelines; whether the pack had been placed on the top or bottom shelf; and cooling time after sterilization. Statistically significant differences (P<0.05) in wet pack incidence were identified for all of these factors. CONCLUSIONS Various factors are associated with wet pack occurrence after steam sterilization. Recommendations for reducing the risk of wet packs include regular maintenance of the steam pipeline, regular replacement of thermal insulation materials for the steam pipeline, and extension of the drying time.

Dimensional accuracy and simulation-based optimization of polyolefins and biocopolyesters for extrusion-based additive manufacturing and steam sterilization.

Polyolefins exhibit robust mechanical and chemical properties and can be applied in the medical field, e.g. for the manufacturing of dentures. Despite their wide range of applications, they are rarely used in extrusion-based printing due to their warpage tendency. The aim of this study was to investigate and reduce the warpage of polyolefins compared to commonly used filaments after additive manufacturing (AM) and sterilization using finite element simulation. Three types of filaments were investigated: a medical-grade polypropylene (PP), a glass-fiber reinforced polypropylene (PP-GF), and a biocopolyester (BE) filament, and they were compared to an acrylic resin (AR) for material jetting. Square specimens, standardized samples prone to warpage, and denture bases (n = 10 of each group), as clinically relevant and anatomically shaped reference, were digitized after AM and steam sterilization (134 °C). To determine warpage, the volume underneath the square specimens was calculated, while the deviations of the denture bases from the printing file were measured using root mean square (RMS) values. To reduce the warpage of the PP denture base, a simulation of the printing file based on thermomechanical calculations was performed. Statistical analysis was conducted using the Kruskal-Wallis test, followed by Dunn's test for multiple comparisons. The results showed that PP exhibited the greatest warpage of the square specimens after AM, while PP-GF, BE, and AR showed minimal warpage before sterilization. However, warpage increased for PP-GF, BE and AR during sterilization, whereas PP remained more stable. After AM, denture bases made of PP showed the highest warpage. Through simulation-based optimization, warpage of the PP denture base was successfully reduced by 25%. In contrast to the reference materials, PP demonstrated greater dimensional stability during sterilization, making it a potential alternative for medical applications. Nevertheless, reducing warpage during the cooling process after AM remains necessary, and simulation-based optimization holds promise in addressing this issue.

Development of a new sterilization method for microalgae media using calcium hypochlorite as the sterilant.

Calcium hypochlorite (Ca(ClO)2), which can be stably stored in powder form for a long period, is widely used as a disinfectant in various fields. A new sterilization process was developed in the present study, where a microalgal medium was sterilized using 0.02% Ca(ClO)2, followed by complete neutralization of the Ca(ClO)2 within 8 h through catalytic reaction of an MnCl2-Na2EDTA complex and a synergistic effect of glucose. When comparing the growth of Chlorella vulgaris in the autoclaved medium, a 2.65 times greater maximum cell growth was observed in cells grown in the medium prepared by treatment of Ca(ClO)2. This result indicates that denaturation of the medium by heat can hinder the growth of some microorganisms. In the case of cultivation of Euglena gracilis, successful culture growth was achieved without growth inhibition or contamination on a medium prepared in the same manner.

Filtration of a multi-serotype glycoconjugate vaccine drug product through sterilizing grade 0.2/0.22 µm pore size filters.

Glycoconjugate vaccines containing multiple serotypes of a bacterial capsular polysaccharide can provide strong immune protection against pathogenic infections. Sterile filtration is an important component of the fill and finish operations in the preparation of these vaccines, with the capacity of the sterile filter limited by membrane fouling. The objective of this study was to examine the performance of a range of commercial 0.2/0.22 µm nominal pore size sterilizing grade filters with both single-layer and dual-layer structures during filtration of a glycoconjugate vaccine drug product consisting of four polysaccharide serotypes. The highly asymmetric Millipore Express showed much higher capacity than the more homogeneous filters, with the support structure of the Express acting as a prefilter that was able to remove foulants thereby protecting the small pores in the size-selective skin layer. This behavior was confirmed by performing experiments with different batch prefilters and by examining the location of foulant deposition within the sterile filters using confocal microscopy. These results provide important insights into the factors controlling fouling by these multiserotype vaccines as well as a framework for increasing the capacity of the sterile filter.

Readability of postoperative discharge instructions is associated with complication rate in companion animals undergoing sterilisation.

BACKGROUND: Readability of client communications is a commonly overlooked topic in veterinary medical education. In human medicine, it has been advised that the readability of patient materials should be at USA schooling sixth-grade level or below. We hypothesised that student written discharge instructions would be of an inappropriate readability level, and discharges scored with higher reading grade levels would be associated with more complications. METHODS: The cohort comprised 149 dogs and cats presenting for sterilisation. The readability of discharge instructions was assessed using the Flesch Reading Ease (FRE) and Flesch-Kincaid Grade Level (FKGL) formulas. Records were examined for evidence of postoperative complications. RESULTS: The mean FRE score of the discharge instructions was 61.97, with 30.87% being classified as 'difficult' or 'fairly difficult', 60.4% as 'standard' and 8.72% as 'fairly easy'. The mean FKGL was 8.64, with 98% being above reading level 6. Overall, there was an association between FKGL and complication occurrence (p = 0.005). Stratification by species demonstrated FRE and FKGL to be associated with complication occurrence in dogs (FRE score, p = 0.038; FKGL, p = 0.002), but not cats (FRE score, p = 0.964; FKGL, p = 0.679). LIMITATIONS: Due to the retrospective nature of the study, there were difficulties associated with extracting relevant complication information from the medical records. CONCLUSION: Only 2% of owner-directed discharge instructions were written at readability levels aligning with the recommendations set forth in the human guidelines.

Effect of ozone sterilization on controlling leaf mildew and gray mold tomato disease in a glasshouse and its influence on other growth parameters.

BACKGROUND: In order to explore the effect of ozone sterilization treatment on tomato disease control and increase fruit setting rate, this study took 906 pink fruit tomato as test material, used a small ozone generator to carry out ozone treatment single-factor test, and then selected orthogonal table to guide the ozone treatment combination. The effects of different ozone treatment concentration, ozone treatment duration and ozone treatment times on the growth, disease and fruit setting rate of potted tomato were analyzed. RESULTS: Different ozone treatment had effects on leaf mildew, gray mold and fruit setting rate of tomato. The influence degree of three factors on leaf mildew, gray mold and fruit setting rate was from large to small, a > b > c, a > c > b, b > a > c. A quadratic regression model was established with the control effect of tomato leaf mildew, gray mold and fruit setting rate as response values, and the optimal parameter combination was determined: The ozone treatment concentration was 0.0465 g kg-1, the ozone treatment time was 30 min, and the ozone treatment times were twice a week. In this case, the control efficiency of tomato leaf mildew was 95.02%, the control effect of gray mold was 99.49%, and the fruit setting rate was 76.5%. The test parameters were accurate and reliable. CONCLUSION: The ozone sterilization method proposed in this article is safe and green, and can provide theoretical support for the recovery and reconstruction of tomato disease in a glasshouse. © 2024 Society of Chemical Industry.

Review on sterilization techniques, and the application potential of phage lyase and lyase immobilization in fighting drug-resistant bacteria.

Many human health problems and property losses caused by pathogenic contamination cannot be underestimated. Bactericidal techniques have been extensively studied to address this issue of public health and economy. Bacterial resistance develops as a result of the extensive use of single or multiple but persistent usage of sterilizing drugs, and the emergence of super-resistant bacteria brings new challenges. Therefore, it is crucial to control pathogen contamination by applying innovative and effective sterilization techniques. As organisms that exist in nature and can specifically kill bacteria, phages have become the focus as an alternative to antibacterial agents. Furthermore, phage-encoded lyases are proteins that play important roles in phage sterilization. The in vitro sterilization of phage lyase has been developed as a novel biosterilization technique to reduce bacterial resistance and is more environmentally friendly than conventional sterilization treatments. For the shortcomings of enzyme applications, this review discusses the enzyme immobilization methods and the application potential of immobilized lyases for sterilization. Although some techniques provide effective solutions, immobilized lyase sterilization technology has been proven to be a more effective innovation for efficient pathogen killing and reducing bacterial resistance. We hope that this review can provide new insights for the development of sterilization techniques.

Effects of heat sterilization on protein physicochemical properties and release of metabolites of braised chicken after in vitro digestion.

Heat sterilization enhances the safety and shelf-life of braised chicken, but its impact on protein digestibility and the release of metabolites remains unclear. Here, braised chicken was sterilized at 80 °C (LS), 100 °C (MS), and 121 °C (HS) for 30 min. Protein digestibility was assessed by in vitro digestion, whereas the release of metabolites was analysed by UPLC-QTOF-MS spectroscopy. Results revealed that LS had higher gastrointestinal digestibility (88.86 %) than MS (81.79 %) and HS (78.13 %). Increased carbonyl content, turbidity, particle size, and hydrophobicity, along with decreased sulfhydryl content and solubility, indicated rising protein oxidation aggregation with higher sterilization temperatures, explaining reduced digestibility. 96 metabolites were identified. Compared to the control group, LS exhibited a statistically significant variation in the biosynthesis of unsaturated fatty acids, MS displayed a significant difference in purine metabolism, and HS showed a significant difference in primary bile acid biosynthesis. Thus, LS is a promising sterilization method.

Sterilization of Human Amniotic Membrane Using an Ozone Hydrodynamic System.

Human amniotic membrane (hAM) is an important biomaterial for Tissue Engineering, due to its great regenerative properties and potential use as a scaffold. The most used procedure to sterilize biomaterials is gamma-irradiation, but this method can affect several properties, causing damage to the structure and reducing the growth factors. The present work evaluated the efficiency of a new method based on ozonated dynamic water for hAM sterilization. HAM fragments were experimentally contaminated with Staphylococcus aureus, Escherichia coli, Candida albicans, Staphylococcus epidermidis, and Clostridium sporogenes (106 CFU/mL) and submitted to sterilization process for 5, 10 and 15 min. The analyses did not reveal microbial activity after 10 min for S. aureus and C. sporogenes and after 15 min for E. coli and S. epidermidis. The microbial activity of C. albicans was reduced with the exposure time increase, but the evaluated time was insufficient for complete sterilization. The depyrogenation process was investigated for different ozonation times (15, 20, 25, 30, and 35 min) to evaluate the ozone sterilization potential and presented promising results after 35 min. The ozone effect on hAM structure was evaluated by histological analysis. A decrease in epithelium average thickness was observed with the exposure time increase. Furthermore, some damage in the epithelium was observed when hAM was exposed for 10 and 15 min. It can indicate that ozone, besides being effective in sterilization, could promote the hAM sample's de-epithelization, becoming a possible new method for removing the epithelial layer to use hAM as a scaffold.

Ultrasonic-assisted synthesis of lignin-based ultrasmall silver nanoparticles for photothermal-mediated sterilization.

Lignin-based silver nanoparticles have been considered a promising antimicrobial material. However, it remains challenging to prepare ultra-small size silver nanoparticles sustainably with superior antibacterial performance. In this work, we modified ethanol-extracted lignin (EL) with carboxymethyl groups and further synthesized ultra-small particle size (3.8 ± 0.1 nm) nanosilver incorporated carboxymethyl lignin complexes (AgNPs@CEL) using ultrasonic technology. Due to the outstanding antibacterial properties of the ultra-small size nanosilver, AgNPs@CEL could cause 5.3 and 5.4 log10 CFU/mL reduction against E. coli and S. aureus in 5 min. Meanwhile, AgNPs@CEL exhibited remarkable photothermal antibacterial performance, which caused 6.2 and 6.1 log10 CFU/mL reduction of E. coli and S. aureus, with NIR irradiation for 5 min. Furthermore, the composite films prepared by doping only 0.5 wt% AgNPs@CEL into ethyl cellose could achieve a bactericidal rate more than 99.99 %. This study provides a new insight into design of controlled particle size lignin-based antibacterial nanosilver materials in a sustainable manner and holds promise for applications in antibacterial fields.

Potential of solid recovered fuel production from autoclave treated healthcare waste in Sultanate of Oman.

Economic growth has a potential impact on waste generation worldwide. Growing recognition for resources recovery from waste including production of a clean energy has led to the development of standards for, and the generation of, Solid Recovered Fuel (SRF). SRF, according to BS EN ISO 21640 is a fuel prepared from nonhazardous/treated waste to be utilized for energy recovery in incineration or co-incineration plants which meets the classification and specification. The amount of combustible fractions (i.e., plastic, textile and paper) that are present in Healthcare Waste (HCW) and Municipal Solid Waste (MSW) provides an opportunity for SRF production. HCW is defined as clinical waste generated from healthcare facilities. Limited efforts in utilizing treated HCW in production of SRF were noted, despite the fact that high content of combustible fractions, hence the novelty of this research. This research addresses the opportunities of utilizing autoclaved HCW as an alternate fuel; through a detailed chemical and physical analysis of autoclaved HCW collected from the Sultanate of Oman hospital and healthcare facilities. Furthermore, this study examines the possible uses of such materials instead of landfilling. The utilization of treated HCW as an alternative fuel is not only saving the land space, but also reduces the carbon emissions originating from landfilling. This in fact would also support the government in achieving its aspiring goal of the net zero carbon emissions by 2050 through better utilization of these materials in production of SRF as an alternative to fossil fuel combustion. The study revealed that autoclaved HCW appears to have a high quality SRF and is classified as (NCV 4, Cl 3); which complies with the potential end users' specifications. It is estimated that the combined energy output from MSW and HCW combustible fractions could cover about 12.75% of the energy requirements for Oman cement factories.Implications: The results confirm the viability of using autoclave (HCW) as an alternative fuel due to its high thermal energy content. Based on mean Net Calorific Value (NCV) of analyzed HCW that is found around 14 (MJ/Kg (ar)), and the mean Cl level (i.e., 0.814 ± 0.213% (d)); the SRF is classified as (NCV4, Cl 3). This grade is found to be well within the end users accepted range. This opens up the opportunity for creating a market demand for HCW that not only it could boost its recovery, but it could also unlock the value that can generates.

Effect of different sterilization methods on the appearance, composition, and flavor of sugarcane juice.

Cold-pressed sugarcane juice (SCJ) is a beverage rich in vitamins, carbohydrates, and antioxidants. Various sterilization methods impact fruit juice's appearance, nutrients, and flavor. Hence, this study aims to assess how different sterilization techniques affect the flavor, appearance, and nutritional value of SCJ. Freshly prepared SCJs were subjected to two sterilization methods: pasteurization (referred to as PTG) and autoclaving (referred to as HTHP). The pasteurization process was carried out at 63°C for 30 min, whereas the HTHP process was applied at 115°C for 30 min. The appearances, Brix value, colors, sugar, organic acid content, and aromatic compounds were determined. The Brix and pH values of the juice show little variation across different heat treatments. The color index of PTG was similar to that of the control group, whereas the L* value of HTHP increased about 21%, resulting in a significant color change. The glucose and fructose contents of HTHP were 7.03 and 5.41 mg/mL, which were much higher than those of PTG (3.26 and 2.33 mg/mL) and control group (3.33 and 2.48 mg/mL). A total of 77 aromatic compounds were identified in the SCJ after various heat treatments. Among them, pentanoic acid, octanal, and ß-damascenone were the most abundant substances contributing to the overall flavor in the control group, PTG, and HTHP. Pasteurization preserved the original flavor of the juice, whereas autoclaving triggered the Maillard reaction, forming pyrazine and furan-like compounds that altered the SCJ's flavor. In conclusion, pasteurization retained SCJ's original characteristics, whereas HTHP induces changes in nutrition and imparts a distinct flavor.

Effect of Vaporized Hydrogen Peroxide and Nitrogen Dioxide Sterilization on Nitinol.

Background: Nitinol is used as the structural framework in numerous types of medical devices (e.g., guidewires, transcatheters, stents). The desire to understand the material compatibility of nitinol with vaporized hydrogen peroxide (VH2O2) and nitrogen dioxide (NO2) sterilization is increasing in healthcare technology. As a result of increased regulatory pressure and capacity limitations related to ethylene oxide (EO) sterilization, the industry is seeking alternative, sustainable sterilization options. Objective: This study sought to characterize the corrosion resistance of nitinol metal alloy wire when exposed to varying levels of VH2O2 and NO2 sterilization. Methods: Scanning electron microscopy (SEM) imaging and energy-dispersive X-ray spectroscopy (EDS) scans were performed to understand the effects of VH2O2 and NO2 sterilization treatments on the surface morphology and chemical composition of nitinol. Results: From the SEM-EDS results, no notable difference was observed when comparing VH2O2 and NO2 test samples with nonsterile control samples. In addition, cyclic potentiodynamic polarization measurements were performed per ASTM F2129-19a to determine corrosion susceptibility. No considerable changes were detected in the electrochemical potential after VH2O2 and NO2 sterilization treatments, when compared with the nonsterile control samples. Conclusion: SEM-EDS and corrosion test results indicated no considerable changes in the surface properties or electrochemical potential of the sterilized samples compared with the nonsterilized control samples. Therefore, nitinol metal showed promising results for compatibility with VH2O2 and NO2 sterilization.

Toward Enhanced Machine-Based Release in X-ray Sterilization.

Trends toward the use of irradiator parameter release (also called machine-based release) put pressure on equipment manufacturers to guarantee accuracy and reliability of monitored process parameters. In the specific case of X-ray processing, relevance of these monitored parameters is questionable due to the additional difficulty coming from the fact that the X-ray converter does not have associated parameters or a monitored feedback mechanism. To bridge this gap, this article presents a novel method to verify in real-time consistency of certain X-ray field properties. It covers the description of an X-ray flux monitor and its experimental characterization. The proposed detector can be used as a control and monitoring tool in addition to the conventional "passive" dosimetry per ISO 11137-1 and ISO 11137-3. It can detect photon flux deviation on the order of magnitude of 1%. Its performance would allow real-time monitoring of each pallet being processed and ensure that the correct X-ray beam is directed to the product. Further, the known response of the detector to a product can serve as a validation that the correct product is in front of the beam. Moreover, a detector of this type could contribute to moving from the current dosimetric release to irradiator parameter release. Compared with current practices, benefits would include an increased number of control points used to verify process conformity, real-time information on the radiation field (process output validation), limited manual handling of dosimeters, and verification that the product treated is the same as the performance qualification dose-mapped product.