Sterilization Purposes Research Articles

A UV-C LED Lamp Driver Circuit Applied to a Direct-Current-Input Voltage Source for Sterilization and Germicidal Applications

UV-C LEDs, which offer short-wavelength characteristics and serve as an alternative to traditional UV mercury lamps, represent a new light source for applications in space decontamination and surface disinfection. This paper presents the design and development of a UV-C LED lamp driver circuit configured to operate with a DC-input voltage source for sterilization and germicidal purposes. The primary circuit integrates a modified buck converter with a flyback converter, resulting in an innovative single-stage, single-switch DC-DC power converter. Additionally, the proposed electronic driver recovers energy stored in the transformer’s leakage inductors, enhancing overall circuit efficiency. A prototype driver circuit with a 3.3 W power rating (10 V/330 mA) is developed for a UV-C LED lamp intended for sterilization and germicidal applications with a DC-input voltage source. The experimental results from the prototype circuit, tested at an 18 V DC input, confirm the functionality of the proposed electronic driver for UV-C LED sterilization and germicidal lighting. Additionally, the circuit achieves efficiency exceeding 91%.

Evaluation of Radiation Safety for Hospital Staff Using Dosimetric Data

Hospitals utilize various manmade radiation sources for therapeutic and sterilization purposes. However, improper monitoring of these sources can lead to radiation leakage, posing potential health risks. At Bir Hospital, data from dosimeters were analysed using appropriate statistical methods. The analysis revealed that the overall absorbed dose is 0.078 mSv per year, well below the 20 mSv annual dose limit recommended by the International Commission on Radiological Protection (ICRP). This indicates that the staff at Bir Hospital are working under safe radiation exposure levels. A Chi-square test further confirmed that there is no significant gender-based variation in radiation dose absorption among the staff. These findings demonstrate that the hospital’s radiation safety measures are effective, ensuring the safety of its employees. This data underscores the importance of maintaining and monitoring radiation safety. To enhance safety standards, it is recommended that all hospitals require medical staff to use dosimeters and provide access to dosimeter data for research and analysis.

Isolation and Diagnosis of Dermatophytes of the Hand Tinea and Sensitivity Study to the Antifungals Griseofulvin

The study was conducted during the month of October 2022 until April 2023, with the aim of isolating and diagnosing the fungi that cause skin diseases from patients visiting the dermatology consultation affiliated with Salah al-Din General Hospital who were diagnosed as infected by dermatologists for the period from 1/6/2022 to 1/ 12/2023 For both sexes, aged between 10 and 60 years, by taking skin samples from the area of infection after wiping them with cotton saturated with 70% alcohol for the purpose of sterilization to get rid of any contaminants. Which was diagnosed clinically by a dermatologist in the dermatology consultation at Salah al-Din General Hospital and outpatient clinics. To evaluate the effectiveness of anti-griseofulvin in inhibiting the isolated fungi, the percentage of dermatophyte infections recorded by positive direct microscopic examination was only (88) patients, representing (88%) of the total number of patients. While the number of negative cases by negative direct microscopic examination was (59), or (59%). As for positive laboratory culture results, there were (79) patients, in the rate of (79%). While the number of negative cases by laboratory culture was (21), in the rate of (21%). The fungal genera that cause skin infections, such as Trychophyton and Microsporum, were isolated, with the genus Trichophyton being the most frequent, with 76 isolates belonging to several species, such as T. mentagrophytes, with a number of 29 isolates, then the fungus T. rubrum, with a number of isolates of 22, then the fungus T. terreste, with a number of isolates of 15, and then fungus T. schoenleinii, with a number of 10 isolates, while only three isolates of the M. canis type were recorded in the genus Microsporum. The results of the susceptibility test of the isolated fungi to Griseofulvin showed that the fungus T. mentagrophytes is more sensitive to the antichrysofulvin, as the average diameter of inhibition reached 32 mm compared to the control, followed by T. rubrum, which had an average diameter of inhibition of 16 mm compared to the control.

Self-powered multifunctional platform based on dual-photoelectrode for dual-mode detection and inactivation of Salmonella enteritidis

Self-powered photoelectrochemical (PEC) sensing is a novel sensing modality. The introduction of dual-mode sensing and photoelectrocatalysis in a self-powered system enables both detection and sterilization purposes. To this end, herein, a self-powered multifunctional platform for the photoelectrochemical-fluorescence (PEC-FL) detection and in-situ inactivation of Salmonella enteritidis (SE) was constructed. The platform utilized Bi4NbO8Cl/V2CTx/FTO as a photoanode and CuInS2/FTO as a photocathode and incubated quantum dot (QDs) signaling probes on the surface of the photocathode. During detection, the system drives the transfer of photogenerated electrons between the dual photoelectrodes through the Fermi energy level difference. The photoanode amplifies the photoelectric signal, while the photocathode is solely dedicated to the immune recognition process. QDs provide an additional fluorescence signal to the system. Under optimal experimental conditions, the multifunctional platform achieves detection limits of 3.2 and 5.3CFU/mL in PEC and FL modes respectively, with a detection range of 2.91×102 to 2.91×108CFU/mL. With the application of an external bias voltage, it further promotes electron transfer between the dual photoelectrodes, inhibits the recombination of photogenerated electrons and holes. It generates a significant amount of superoxide radicals (·O2-) in the cathodic region, resulting in strong sterilization efficiency (99%). The constructed self-powered multifunctional platform exhibits high sensitivity and sterilization efficiency, it provides a feasible and effective strategy to enhance the comprehensive capability of self-powered sensors.

A promising eco-friendly and cost-effective photocatalytic rolled graphene oxide/poly(m-methylaniline) core-shell nanocomposite for antimicrobial action.

A new and innovative rolled graphene oxide (roll-GO)/poly-m-methylaniline (PmMA) core-shell nanocomposite has been successfully synthesized using an in situ polymerization technique. This eco-friendly and cost-effective material shows great promise due to its antimicrobial properties. The characterization of the nanocomposite involved X-ray diffraction and Fourier transform infrared spectroscopy to analyze its structure and functional groups, whereas scanning electron microscopy and transmission electron microscopy (TEM) were utilized to examine its morphology. TEM analysis revealed the formation of roll-GO, forming multi-walled tubes with inner and outer diameters of 50 and 70nm, respectively. Optical analysis demonstrated an enhanced bandgap in the nanocomposite, with bandgap values of 2.38eV for PmMA, 2.67eV for roll-GO, and 1.65eV for roll-GO/PmMA. The antibacterial efficacy of the nanocomposite was tested against Gram-positive bacteria, including Bacillus subtilis and Staphylococcus aureus, as well as Gram-negative bacteria such as Escherichia coli and Salmonella sp. The well diffusion method was used to determine the inhibition zones, revealing that the nanocomposite demonstrated broad-spectrum antibacterial activity against all the pathogens tested. The largest inhibition zones were observed for B. subtilis, followed by S. aureus, E. coli, and Salmonella sp. Notably, the inhibition zones increased when the samples were exposed to light compared to dark conditions, with increases of 33 and 18mm noted for B. subtilis. This enhanced activity under light exposure is attributed to the photocatalytic properties of the nanocomposite. The antibacterial mechanism is based on both adsorption and degradation processes. Moreover, antibacterial activity was found to increase with increasing concentrations of nanoparticles, ranging from 100 to 500ppm. This suggests that the nanocomposite has potential as an alternative to antibiotics, especially considering the growing issue of bacterial resistance. The promising results obtained from the inhibition zones make these nanocomposites suitable for various applications. Currently, the research team is working on the development of a prototype utilizing these antimicrobial particles within commercial bottles for sterilization purposes in factories and companies.

Peritoneal bile granuloma formation at the site of caesarean surgical scar

Bile granuloma is a rare complication associated with cholecystectomy about which few case reports have been written. Herein we present the case of a patient who underwent laparoscopic bilateral salpingectomy for the purpose of sterilization and was incidentally found to have a linear collection of bile granulomas along the site of adhesions from her cesarean section. We also present a review of case reports on bile granuloma that have presented in OB/GYN and suggest that this rare pathology should be cited as a differential more often when considering intra-abdominal pathology, particularly for pelvic surgeons. We argue that this condition is likely more common than previously thought and suggest that without further research into this topic, routine biopsy or removal of encountered lesions may not always be necessary in patients at low likelihood for having a malignant pathology.

Built-in electric field mediated S-scheme charge migration in COF/In2S3 heterojunction for boosting H2O2 photosynthesis and sterilization

Built-in electric field mediated S-scheme charge migration in COF/In2S3 heterojunction for boosting H2O2 photosynthesis and sterilization

The influence of electron beam and gamma irradiation on paclitaxel-loaded nanoparticles of fully randomized copolymers in relation to potential sterilization

The influence of electron beam and gamma irradiation on paclitaxel-loaded nanoparticles of fully randomized copolymers in relation to potential sterilization

Silk Fibroin/PLA 3D Printed Composite Stent Fabricated through Direct Ink Write Technology

Bioresorbable alternatives are emerging on the market as alternatives to the cardiovascular stents that are implanted nowadays. Permanent drug-eluting stents are no longer the only viable option during an angioplasty surgical procedure. The new generation of medical stents aims to degrade the device within the artery walls after its function has been completed. In this context, biological materials that degrade inside the body without creating toxic residues such as silk fibroin (SF) are very promising materials for such applications. Moreover, SF has been reported to have non-thrombogenic properties and to reduce the immune response compared to other synthetic polymers, making it ideal for this application. SF has been printed through additive manufacturing techniques such as direct ink write. This study proposes to fabricate a composite stent by combining polylactic acid (PLA) and SF. In this way, it is expected to obtain a stent with potential for a two-phase drug release. A fast burst with the degradation of the SF and a slower drug release period with the degradation of the PLA. For this purpose, stents were fabricated with a PLA and chloroform ink (24.5 % w/v). The last layer of the stent was fabricated with a SF water-based ink at 56.69-60.09 % w/w. Finally, the stents were immersed at different times in ethanol and exposed to 30' of ultraviolet light for sterilization purposes. The degradation results indicate that 24h is sufficient to degrade almost completely the last layer of SF. These results are significant as the SF layer could potentially be used as a carrier for drug delivery, providing biocompatibility and drug release at the earliest post-intervention stage.

Dose mapping of the 60Co gamma irradiation facility and a real irradiated product – Measurements and Monte Carlo simulation

Dose mapping of the 60Co gamma irradiation facility and a real irradiated product – Measurements and Monte Carlo simulation

A quaternary ammonium salt grafted tannin-based flocculant boosts the conjugative transfer of plasmid-born antibiotic resistance genes: The nonnegligible side of their flocculation-sterilization properties

This study developed dual-function tannin-based flocculants, namely tannin-graft-acrylamide-diallyl dimethyl ammonium chloride (TGCC-A/TGCC-C), endowed with enhanced flocculation-sterilization properties. The impacts of these flocculants on proliferation and transformation of antibiotic resistance genes (ARGs) among bacteria during the flocculation-deposition process were examined. TGCC-A/TGCC-C exhibited remarkable flocculation capacities towards both Escherichia coli and Staphylococcus aureus, encompassing a logarithmic range of initial cell density (108-109CFU/mL) and a broad pH spectrum (pH2-11). The grafted quaternary ammonium salt groups played pivotal parts in flocculation through charge neutralization and bridging mechanisms, concurrently contributing to sterilization by disrupting cellular membranes. The correlation between flocculation and sterilization entails a sequential progression, where an excess of TGCC, initially employed for flocculation, is subsequently consumed for sterilization purposes. The frequencies of ARGs conjugative transfer were enhanced in bacterial flocs across all TGCC treatments, stemming from augmented bacterial aggregation and cell membrane permeability, elicited stress response, and up-regulated genes encoding plasmid transfer. These findings underscore the indispensable role of flocculation-sterilization effects in mediating the propagation of ARGs, consequently providing substantial support for the scientific evaluation of the environmental risks associated with flocculants in the context of ARGs dissemination during the treatment of raw water featuring high bacterial density.

Engineering of Schottky heterojunction in Ru@Bi2S3/Nb2C MXene based on work function with enhanced carrier separation for promoted sterilization

Engineering of Schottky heterojunction in Ru@Bi2S3/Nb2C MXene based on work function with enhanced carrier separation for promoted sterilization

A CASE STUDY OF CAT STERILIZATION IN KARANGWUNI, YOGYAKARTA: IMPACTS PERCEIVED BY CARETAKERS AND THEIR UNDERSTANDING OF THE PROGRAM

There is yet to be collected the number of cats in Indonesia, including free- roaming cats. Studies have shown that there is a connection between sterilization and free-roaming cats’ health and welfare. In 2021, Suara Suaka Indonesia decided to hold a small-scale sterilization program in a neighborhood called Karangwuni, Yogyakarta to contribute in lowering cat population. In this case study, we focus on the effect of sterilization to cats that are perceived by humans. Survey was done using Google Forms, taking information on their demographics, involvement with Suara Suaka Indonesia, feedback on their cats’ post-surgery changes and their understanding on sterilization. Respondents are generally satisfied with the impact sterilization has on them and their cats, this is supported by how they perceive sterilization as important and their willingness to recommend the procedure to other people. However, there can still be improvement on delivering messages of sterilization to ensure that the purpose, process, and impact of sterilization can be adequately understood by all participants of the program.

UV Sterilization Biological Safety Cabinet

Abstract: In the past three years COVID-19 has been a major health concern. The World Health (WHO) Organization declared COVID-19 as a pandemic and WHO said that the chances of more pandemics happening in near future are very high. To avoid such pandemics basic safety measures, have to be taken seriously such as sanitization and sterilization. COVID-19 was identified to be transmitting through various mediums such as currencies, cards, daily household objects, medical supplies and etc. Things like PPE kit, surgical masks and N95 respirators are crucially important for the safety of patient and medical personnel working during the pandemic. Due to the pandemic the demandof safety kits outnumbered the supply and medical professionals were left to use the already used PPEkits. The primary goal of the Biological Safety Cabinet(BSC) is to sterilize things like medical equipment anddaily use objects. Ultraviolet (UV) light is used for the purpose of disinfection or sterilization of rooms and surfaces. UV-C has germicidal properties but it is also harmful for human beings. Hence, for the purpose of sterilization without human interference, a UV BSC has been designed to sterilize daily use objects and medical essentials.

Studies on the comparative effectiveness of X-rays, gamma rays and electron beams to inactivate microorganisms at different dose rates in industrial sterilization of medical devices

Studies on the comparative effectiveness of X-rays, gamma rays and electron beams to inactivate microorganisms at different dose rates in industrial sterilization of medical devices

Antimicrobial properties of heterojunction BiSnSbO6-ZnO composites in wastewater treatment.

BiSnSbO6-ZnO composite photocatalytic material with type II heterojunction structure was synthesized by a simple solid-phase sintering method, it was characterized by XRD, UV-vis, and PT methods. The photocatalytic antibacterial experiments were carried out under LED light irradiation. The experimental results showed that the photocatalytic antibacterial properties of BiSnSbO6-ZnO composites against bacteria and fungi were significantly stronger than those of single BiSnSbO6 and ZnO. Under light conditions, the antibacterial efficiencies of 500mg/L BiSnSbO6-ZnO composites against E. coli, S. aureus, and P. aeruginosa reached 99.63%, 100%, and 100% for 6h, 4h, and 4h, respectively. The best antibacterial concentration of BiSnSbO6-ZnO composite against the eukaryotic microorganism Candida albicans was 250mg/L, and the antibacterial efficiency reached the highest 63.8% at 6h. Antibacterial experiments were carried out on domestic livestock and poultry wastewater, which showed that the BiSnSbO6-ZnO composite photocatalytic material has broad-spectrum antibacterial activity against bacteria, and the antibacterial effect has species differences. Through the MTT experiment, it is proved that the prepared BiSnSbO6-ZnO composite photocatalytic material has no toxicity at the experimental concentration. According to the free radical scavenging experiment and SEM observation of the morphological changes of the bacteria after light treatment, the prepared BiSnSbO6-ZnO composite photocatalytic material can generate active species OH, h+, and e- through light irradiation to achieve the purpose of sterilization, where e- play a major role, indicating that the BiSnSbO6-ZnO composite photocatalytic material has broad application prospects in the actual antibacterial field.

Pelatihan Sterilisasi Alat Dan Bahan Medis Pada Anggota Tim Bantuan Medis Vertebrae Fakultas Kedokteran Universitas Pattimura

The Vertebrae Medical Assistance Team (TBM) of the Faculty of Medicine, University of Pattimura is a student organization that has many work programs, and one of their work programs is community service. Medical students will become doctors who will take part in society and who are not only required to be capable and competent in solving all health problems, but also must be able to become examples and role models in moving healthy life for the community. As part of the TBM, medical students are required to have basic medical assistance competencies, therefore, the purpose of this activity is to provide detailed knowledge of sterilization and disinfection techniques that have been neglected so far, starting with simple basic knowledge. In general, the implementation methods used in this community service are sterilization education, sterilization objectives, types of sterilization, and the practice of using autoclave sterilizers. This community service activity has achieved the main planned objectives, namely increasing the knowledge and understanding of participants through sterilization training for medical equipment and materials as part of the program to increase the competence of TBM members. There are three main components discussed in the understanding and skills of participants, namely understanding the definition and purpose of sterilization, understanding the types of sterilization, and being able to practice how to use autoclave sterilizers

Electrochemical Detection of H2O2 Using an Activated Glassy Carbon Electrode

Hydrogen peroxide (H2O2) is extensively used for sterilization purposes in the food industries and pharmaceuticals as an antimicrobial agent. According to the Food and Agriculture Organization (FAO), the permissible level of H2O2 in milk is in the range of 0.04 to 0.05% w/v, so it has been prohibited to use as a preservative agent. Herein, we reported the electrochemical sensing of H2O2 in milk samples using an activated glassy carbon electrode (AGCE). For this purpose, activation of GCE was carried out in 0.1 M H2SO4 by continuous potential sweeping between −0.7 to 1.8 V for 25 cycles. The AGCE showed a redox peak at -0.18 V in the neutral medium corresponding to the quinone functional groups present on the electrode surface. AGCE was studied in (pH 7.4) 0.1 M PBS for the electro-catalysis of H2O2. The surface of the activated electrode was analysed by Raman spectroscopy and contact angle measurements. In addition, for the activated surface, the contact angle was found to be 85° which indicated the hydrophilic nature of the surface. The different optimization parameters such as (1) effect of electrolyte ions, (2) electrooxidation cycles, and (3) oxidation potential windows were studied to improve the activation process. Finally, AGCE was used to detect H2O2 from 0.1 to 10 mM and the limit of detection (LOD) was found to be 0.053 mM with a linear correlation coefficient (R2) of 0.9633. The selectivity of the sensor towards H2O2 was carried out in the presence of other interferents. The sensitivity of the AGCE sensor was calculated as 17.16 μA mol cm−2. Finally, the commercial application of the sensor was verified by testing it in milk samples with H2O2 in the recovery range of 95%–98%.

Antipathogenic upcycling of face mask waste into separation materials using green solvents

The use of disposable face masks has considerably contributed toward waste generation, particularly during the current COVID-19 pandemic. Little attention has been dedicated to the actual examination of recycling strategies for increasing the life cycle of this biomedical waste, as the most common treatment for disposing used masks is incineration. In this study, we screened green solvents for the recycling of face masks by taking advantage of their antipathogenic nature for sterilization purposes. This work is timely and unique because it presents for the first time the successful recovery of polypropylene from face masks, and upcycle of the masks into either a microbead or free-standing membranes as separation materials. Owing to their excellent chemical stability, the membranes are well-suited for organic solvent nanofiltration. The fabricated membranes exhibited molecular weight cut-off values between 665 and 964 g mol −1 , which were fine-tuned by adjusting the coagulation bath temperature from 20 °C to 60 °C. The membranes demonstrated long-term stability over 5 days of continuous filtration at 30 bar, with rejection values exceeding 98% for roxithromycin and rose bengal. This scalable methodology for upcycling used face masks into high-value products has the potential to reduce a crucial environmental threat associated with the global rapid growth of the face mask market. Sustainable transformation of biomedical face mask waste into polypropylene products and nanofiltration membranes using green solvents. • A methodology for upcycling biomedical hazardous materials associated with the COVID-19 pandemic • Use of green solvents for treating face mask waste via the dissolution–precipitation method • Sustainable recovery of polypropylene microbead products from face mask waste • Free-standing and solvent-resistant nanofiltration membranes fabricated from face mask waste • Control of the morphology and the molecular sieving performance of the upcycled membranes.

The Impact of Gaseous Ozone Penetration on the Disinfection Efficiency of Textile Materials

ABSTRACT The utilization of gaseous ozone (a powerful oxidant) in air, for disinfection and sterilization purposes, has been extensively studied for diverse applications; however, the optimal deployment of this technology for textile disinfection is deserving of further research attention and is this the focus of this work. In this study, the penetration efficiency of ozone gas into hard-to-reach regions of different garment types is critically examined. The impacts of garment packing density, hanging orientation and ozonation duration are also considered, and the resultant disinfection efficiencies are comparatively analyzed. An ozonation chamber fitted with remote ozone detection is utilized for the ozonation of fabric swatches inoculated with Escherichia coli bacteria. The number of colony-forming units per cm2 and the bacterial lawn area fraction are evaluated pre- and post-ozonation to quantify the level of disinfection. This study shows that the attainment of sufficient ozone concentrations in hard-to-reach regions of different garment types coupled with the inter-garment spacing utilized are vital for effective decontamination. This study also demonstrates the effectiveness of ozonation as a necessary technology for decontamination, particularly in this era, where the sterilization of textiles and other materials is paramount for public health and safety.