1217. Predicting the Efficacy of an Antimicrobial Surface Coating Utilizing X-Ray Fluorescence Spectroscopy (XRF)

Abstract Background Contaminated surfaces are a critical risk factor for transmitting infectious disease. Current disinfection products provide short-term antimicrobial action; however, these surfaces can be re-contaminated within hours after cleaning. To address this limitation, long-lasting antimicrobial polymer coatings have been developed as an adjunct to traditional disinfecting and cleaning protocols. Due to the micro-scale thickness and transparency of the coating, confirmation of its presence on surfaces is difficult with conventional methods; therefore, this study explores a novel approach to measuring durable polymer coatings on stainless steel coupons to validate their presence and relative antimicrobial activity. Methods In this study, we utilized a hand-held X-ray fluorescence spectroscopy (XRF) analyzer to quantitatively evaluate the amount of antimicrobial polymer coating deposited on stainless steel test surfaces. Stainless steel surfaces with amounts of coating ranging from 0.12 to 3.60 mg/in.2 were analyzed for their XRF profile using a hand-held spectrometer. Additionally, the relationship between the XRF spectra and antimicrobial activity was evaluated using a modified version of an existing sanitization protocol for hard surfaces using Staphylococcus epidermidis as the test organism. Results Comparison of the amount of antimicrobial polymer coating (in mg) and the XRF values (photon count) revealed a calibration curve with a high degree of linearity (R2 = 0.993) especially for surfaces that had lower mass (Figure 1). In addition, the relationship between XRF values and antimicrobial efficacy also were found to be well-correlated with a logarithmic trend (R2 = 0.9308) (Figure 2). Conclusion The observed trends between coating mass, XRF value and antimicrobial efficacy suggests that these analytical techniques are viable options for determining the presence of invisible antimicrobial polymer coatings. Additionally, laboratory-based calibration curves based on XRF values can be used to predict the level of antimicrobial activity of surfaces that have been treated with polymer coatings. These findings suggest that the use of a hand-held XRF spectrometer can be a rapid and cost-effective method for assessing the presence and efficacy of polymer coatings. Disclosures All authors: No reported disclosures.

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PROPUESTA DE UNA METODOLOGÍA PARA CUANTIFICAR LA ACTIVIDAD ANTIBACTERIANA DE LA MIEL

FAVE Sección Ciencias Veterinarias ◽

10.14409/favecv.v19isuplemento.10934 ◽

2021 ◽

Vol 19 (suplemento) ◽

Author(s):

A Ferrer

Keyword(s):

Stainless Steel ◽

Antibacterial Activity ◽

Inhibitory Concentration ◽

Agar Plate ◽

Test Organism ◽

Diffusion Method ◽

Medicinal Purpose ◽

Inhibitory Zone ◽

Petri Dishes ◽

The Relationship

In this study a standardized method for objectively comparing the antibacterial activity of honey was developed. The assay was performed using a strain of S. aureus and four honeys that have been shown antibacterial activity against this strain. The antibacterial activity of honeys were checked by using an agar plate diffusion method using S. aureus (ATCC 29213) as the test organism. On the surface of each agar plate six stainless steel cylinders with a diameter of 8,14 mm were radially disposed. Onto each cylinder 0,1 mL of sample honey at 10% v/v was placed and all Petri dishes were incubated at 35°C during 24 h. Each sample were analyzed by triplicate. The surface of the cylinder diameter was set as reference antibacterial activity equivalent to minimal inhibitory concentration (MIC). The antibacterial activity of each honey was quantitated by the relationship between the surface of the inhibitory zone and the surface of the reference activity expressed as multiples of MIC (x MIC). The method allowed establishing differences between the bacterial activities of the different honeys tested and could be used for identifying honeys that could be employed with medicinal purpose for the treatments of wounds.

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Interface Structure of Be/HR-1Stainless Steel by Vacuum Diffusion Bonding

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.314-316.968 ◽

2011 ◽

Vol 314-316 ◽

pp. 968-971

Author(s):

Hui Li ◽

Shang Qi Zhou ◽

Ji Lan Kong

Keyword(s):

Stainless Steel ◽

Diffusion Bonding ◽

Testing Machine ◽

Interface Structure ◽

Structure And Properties ◽

X Ray Diffraction ◽

X Ray ◽

Composition And Structure ◽

Material Testing Machine ◽

The Relationship

Be and HR-I stainless steel with AgCu28 as an interlayer was diffusion bonded by hot pressing，The microstructure，distribution of composition and phase，mechanical properties of the joints were analyzed using scanning electron microscopy(SEM)，scanning auger microspectroy(SAM)，x-ray diffraction(XRD) and material testing machine，and the relationship between composition and structure and properties，and the effect of interlayer materials AgCu28 alloy were also discussed．The results show that good joint can be obtained using AgCu28 alloy as an interlayer material，because it can reduce the mutual diffusion between beryllium and stainless steel elements，the formation of brittle intermetallic compounds between beryllium and stainless steel elements are avoided effectively to improve the diffusion bonding strength and properties．

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Encapsulation of Essential Oils within a Polymeric Liposomal Formulation for Enhancement of Antimicrobial Efficacy

Natural Product Communications ◽

10.1177/1934578x1000500912 ◽

2010 ◽

Vol 5 (9) ◽

pp. 1934578X1000500 ◽

Cited By ~ 7

Author(s):

Sandy F. van Vuuren ◽

Lisa C. du Toit ◽

Ashleigh Parry ◽

Viness Pillay ◽

Yahya E. Choonara

Keyword(s):

Antimicrobial Activity ◽

Essential Oils ◽

Polymer Coating ◽

Chitosan Solution ◽

Antimicrobial Efficacy ◽

Polymeric Coating ◽

Limiting Factor ◽

Layer By Layer ◽

Positive Effects ◽

The Stability

Essential oils and their constituents are known to possess antimicrobial activity; however, their inherent volatility is a limiting factor. In order to exploit the antimicrobial efficacy of essential oils, encapsulation within polymeric liposomal systems was undertaken. The liposomes were subsequently polymer-coated in order to further enhance the stability of the formulations. Essential oils distilled from Artemisia Afra, Eucalyptus Globulus and Melaleuca alternifolia were encapsulated into diastearoyl phosphatidylcholine and diastearoyl phosphatidylethanolamine liposomes employing a reverse phase evaporation methodology. A polyelectrolyte coating was then applied via the layer-by-layer self-deposition technique. A batch of the liposomes was polymer-coated with a 0.15%w/v chitosan solution. Using the minimum inhibitory concentration assay, the liposome-encapsulated, unencapsulated and polymer-coated liposome-encapsulated essential oils were compared in order to observe whether the antimicrobial efficacy was improved with encapsulation and polymer coating. Fractional inhibitory concentrations (FICs) were calculated in order to determine the antimicrobial interactions amongst the lipoid components, polymer coating and essential oils (synergistic, additive, indifferent and antagonistic interactions). With the exception of A. afra, microbial growth was inhibited at lower concentrations for the encapsulated formulations in comparison with the non-encapsulated oils. Synergistic to additive interactions were noted for encapsulated E. globulus (ΣFIC values 0.25-0.45) and M. alternifolia (ΣFIC values 0.26-0.52) formulations. The addition of the polymer coating did not enhance antimicrobial activity, but owing to their positive effects on membrane stability, its presence is important as a means of extending the shelf life of these formulations. Additionally, the presence of the polymeric coating availed the essential oil at a slower rate. This investigation is a stepping stone towards the promotion of the antimicrobial use of essential oils. The added benefits are that essential oils not only provide effective antimicrobial efficacy, but also promote a “greener” consumerism. Within liposomes, they will enhance dermato-cosmetic properties and increase the marketing image of the final product.

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Hubungan antara Luas Lesi pada Foto Toraks Penderita TB Paru Dewasa yang Memiliki Riwayat Diabetes Melitus dengan Indeks Massa Tubuh di Rumah Sakit Hasan Sadikin Bandung

Jurnal Radiologi Indonesia ◽

10.33748/jradidn.v1i3.18 ◽

2016 ◽

Vol 1 (3) ◽

pp. 138-144

Author(s):

Ina Edwina ◽

Rista D Soetikno ◽

Irma H Hikmat

Keyword(s):

Chest Radiograph ◽

Chi Square ◽

Pulmonary Tb ◽

X Ray ◽

Consecutive Sampling ◽

Close Relationship ◽

Chi Square Test ◽

Chest X Ray ◽

The Relationship ◽

Diabetes Melitus

Background: Tuberculosis (TB) and diabetes mellitus (DM) prevalence rates are increasing rapidly, especially in developing countries like Indonesia. There is a relationship between TB and DM that are very prominent, which is the prevalence of pulmonary TB with DM increased by 20 times compared with pulmonary TB without diabetes. Chest X-ray picture of TB patients with DM is atypical lesion. However, there are contradictories of pulmonary TB lesion on chest radiograph of DM patients. Nutritional status has a close relationship with the morbidity of DM, as well as TB.Objectives: The purpose of this study was to determine the relationship between the lesions of TB on the chest radiograph of patients who su?er from DM with their Body Mass Index (BMI) in Hasan Sadikin Hospital Bandung.Material and Methods: The study was conducted in Department of Radiology RSHS Bandung between October 2014 - February 2015. We did a consecutive sampling of chest radiograph and IMT of DM patients with clinical diagnosis of TB, then the data was analysed by Chi Square test to determine the relationship between degree of lesions on chest radiograph of pulmonary TB on patients who have DM with their BMI.Results: The results showed that adult patients with active pulmonary TB with DM mostly in the range of age 51-70 years old, equal to 62.22%, with the highest gender in men, equal to 60%. Chest radiograph of TB in patients with DM are mostly seen in people who are obese, which is 40% and the vast majority of lesions are minimal lesions that is equal to 40%.Conclusions: There is a signifcant association between pulmonary TB lesion degree with BMI, with p = 0.03

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