Effect of DMPEI coating against biofilm formation on PVC catheter surface.

Urinary tract infections (UTIs) are a significant cause of morbidity in healthcare systems and are prominently associated with applying urethral catheters, particularly in surgeries. Polyvinyl chloride (PVC) is extensively utilized in the fabrication of catheters. Biofilms, complex polymeric constructions, provide a protective milieu for cell multiplication and the enhancement of antibiotic resistance. Strategies to counteract biofilm development on medical apparatuses' surfaces incorporate antimicrobial agents such as N,N-dodecyl, and methyl polyethylenimine (DMPEI). This research endeavored to characterize the morphology of PVC and PVC-DMPEI surfaces utilizing Scanning Electron Microscopy (SEM) and Atomic Force Microscopy (AFM) and to gauge hydrophobicity through contact angle measurements. Employing Escherichia coli, Staphylococcus aureus, and Candida albicans in adhesion assays enabled the assessment of DMPEI's efficacy in preventing microbial adherence to PVC. Butanol successfully solubilized 2 mg.mL-1 DMPEI without altering the PVC structure. SEM results substantiated the formation of a DMPEI layer on the PVC surface, which led to decreased surface roughness, as validated by AFM, and increased hydrophilicity, as demonstrated by contact angle evaluations. E. coli, S. aureus, and C. albicans exhibited significant adhesion reduction, 89.3%, 94.3%, and 86.6% on PVC-DMPEI surfaces. SEM visualizations confirmed reduced cellular colonization on PVC-DMPEI and highlighted considerable morphological modifications in E. coli. Consequently, DMPEI films effectively minimize the adhesion of E. coli, S. aureus, and C. albicans on PVC surfaces. DMPEI, with its potential as a protective coating for innovative medical devices, promises to inhibit biofilm adherence effectively.

Impact of DMPEI on Biofilm Adhesion on Latex Urinary Catheter.

BACKGROUND: Microorganisms can migrate from the external environment to the patient's organism through the insertion of catheters. Despite being indispensable medical device, the catheter surface can be colonized by microorganisms and become a starting point for biofilm formation. Therefore, new technologies are being developed in order to modify surfaces to prevent the adhesion and survival of microorganisms. Patents with the use of DMPEI have been filed. OBJECTIVE: In the present work, we coated latex catheter surfaces with 2 mg mL-1 DMPEI in different solvents, evaluated the wettability of the surface and the anti- biofilm activity of the coated catheter against Escherichia coli, Staphylococcus aureus, and Candida albicans. METHODS: We coated the inner and outer catheter surfaces with 2 mg mL-1 of DMPEI solubilized in butanol, dimethylformamide, and cyclohexanone and the surfaces were analyzed visually. Contact angle measurement allowed the analysis of the wettability of the surfaces. The CFU mL-1 count evaluated E. coli, S. aureus, and C. albicans adhesion onto the control and treated surfaces. RESULTS: The contact angle decreased from 50.48º to 46.93º on the inner surface and from 55.83º to 50.91º on the outer surface of latex catheters coated with DMPEI. The catheter coated with DMPEI showed anti-biofilm activity of 83%, 88%, and 93% on the inner surface and 100%, 92%, and 86% on the outer surface for E. coli, S. aureus, and C. albicans, respectively. CONCLUSION: Latex catheter coated with DMPEI efficiently impaired the biofilm formation both on the outer and inner surfaces, showing a potential antimicrobial activity along with a high anti-biofilm activity for medical devices.

Recent Patents on the Industrial Application of Alpha-amylases.

BACKGROUND: Alpha-amylases are enzymes capable of degrading polysaccharides, such as starch and glycogen. Found in various organisms, such as fungi and bacteria, these enzymes have great biotechnological potential due to their insertion in several industrial sectors ranging from food to biofuels. OBJECTIVE: The aim of this study was to analyze patents deposited in intellectual property databases on alpha-amylases in the fields of food, beverages, detergents, animal feeds, biofuels, pharmaceuticals and textiles, with the search period being 5 years. METHODS: This study targeted the use of alpha-amylases in various industrial sectors, so searches were carried out on the intellectual property database Espacenet website (European Patent Office - EPO) which contains more than 90 million patents deposited in its database. RESULTS: During the search for patents filed in the last 5 years, 186 were found related to the use of alpha-amylases. These were disturbed as follows: 84 (biofuel), 41 (drinks), 16 (pharmaceuticals), 15 (detergents), 11 (food), 10 (animal feed), 9 (textiles). From the total number of patents found, we selected 6 from each area, except pharmaceutical products, to discuss and provide information on the application of this enzyme. CONCLUSION: This study demonstrated that the sectors of beverages and animal feed have preferences for thermostable alpha-amylases while sectors such as food, biofuels and textiles only regarded the importance of enzymatic efficiency. The detergent sector presented the greatest use of alpha-amylases which had distinct biochemical characteristics as solvent resistance and thermostability. The pharmaceutical sector was the one that presented less patents related to the application of alpha amylases. In addition, this work showed that China is the country with the highest patent registration for the use of alpha-amylases in the analyzed period.