Production of antibacterial glass using nano silver

THE JOINT ACADEMIC PROGRAM OF EXECUTIVE MASTER IN SCIENCES AND MANAGEMENT OF THE ENVIRONMENT BETWEEN INDUSTRIAL UNIVERSITY OF HOCHIMINH CITY AND LIÈGE UNIVERSITY LIÈGE Xi.H Université INDUSTRIAL UNIVERSITY OF HOCHIMIMH CITY TA DUC TRUNG PRODUCTION OF ANTIBACTERIAL GLASS USING NANO SILVER Major: EXECUTIVE MASTER IN SCIENCES AND MANAGEMENT OF THE ENVIRONMENT MASTER’S THESIS HOCHIMINH CITY, 2022 The project was completed at The Industrial University of Hochiminh City Supervisor’s name: Associate Prof Le Hung Anh (Write full name and signature) The thesis was taken at The Industrial University of Hochiminh City date 17 February, 2023 Committee members (name): Associate Prof Nguyen Thanh Binh - Committee Chair Dr Nguyen Thi Thanh True - Commissioner Dr Nguyen Thi Ngoc - Secretary (Write full name and signature) COMMITTEE CHAIR DEAN OF INSTITUTE OF ENVIRONMENTAL SCIENCE, ENGINEERING AND MANAGEMENT POS TS LÊ HỪNG ANH ACKNOWLEDGEMENTS In order to complete this graduation thesis report, I have received a lot of help, guidance and input from many people First of all, I would like to express my sincere thanks to my instructor - lecturer ofHo Chi Minh City University of Industry - Assoc Dr Le Hung Anh and Dr Pham Trung Kien - lecturer at Ho Chi Minh City University of Technology, during the past time, he has guided me very enthusiastically Thanks to the guidance of the teacher, I know how to study, work and research topics scientifically and effectively And thanks to the dedicated guidance and guidance of the teacher, I have gained a lot of knowledge, so that I can complete this graduation thesis report Sincere thanks to the laboratory staff, of the Institute of Science, Technology and Environment Management and the Faculty of Materials Technology for creating the best conditions for equipment and tools during the experiment period At the same time, I would like to express my thanks to the previous classmates of the environment, the wedsite management boards for documents on the environment for creating conditions for the team to learn and investigate and survey to get the completed data project plan Although I have tried to complete the report as much as possible, it inevitably has shortcomings, I hope to receive valuable contributions from teachers and professors i ABTRACT Nanosilver (AgNPs) has good bactericidal ability to create a clean environment, minimizing the possibility of spreading diseases from glass and porcelain surfaces The subject covered the nano silver layer on the glass surface by dipping and spinning coating technique Through the methods: FT-IR (assessment of physical and chemical characteristics of solution), thereby determining coconut oil is a good solvent, and the ratio of resinate and coconut oil 1:20 (with gram of solid resinate: 20 ml of coconut oil) selected as the optimal ratio to cover silver resintae with glass XRD (identifying the product to be nano silver), SEM (determining the size of the particle after calcination), EDX (determining the composition of glass material after calcination with Ag + ions), ƯV-VIS (measuring the transmittance of materials after silver nanoparticles) a defined topic on the glass surface exists a layer of nano silver, the size of the nanoparticles is relatively evenly distributed on the surface of coated glass and the glass sample after coating has uv resistance is quite good In addition, the antibacterial test with five types of bacteria causing hospital infections is Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa, Salmonella Typhimurium, Bacillus cereus, the silver-coated glass for silver has very good results All samples influenced the growth of bacteria, with the two types of Escherichia coli Pseudomonas aeruginosa giving complete resistance Since then, the thesis has had high applicability to reality and is the foundation for some economic sectors in general and the hospital environment in particular ii TABLE OF CONTENTS LIST OF TABLE V LIST OF FIGURES V LIST OF ABBREVIATIONS vi CHAPTER 1: INTRODUCTION 1.1 The necessity of the topic 1.2 Objectives of the study 1.3 Object of research - Scope of research 1.3.1 Research subjects 1.3.2 Research scope 1.4 Research content 1.5 Scientific and practical meanings 1.6 Novelty of the topic CHAPTER OVERVIEW 2.1 Introduction of silver nanomaterials 2.1.1 Silver nano concept 2.1.2 The characteristics of nano silver 2.1.3 Antiseptic mechanism of nano silver 2.1.4 Methods of synthesizing nano silver 2.1.5 Application of nano silver , 10 2.2 Overview of coconut oil 13 2.2.1 General introduction about coconut oil 13 2.2.2 Coconut oil production technology 14 2.2.3 Application 17 2.3 Methods of creating films 18 2.3.1 Physical method 18 2.3.2 Chemical method (Sol - gel) 21 CHAPTER 3: MATERIALS AND METHODS .28 3.1 Materials and tools 28 3.2 The research methodology 30 3.3 Test design 31 iii CHAPTER 4: RESULTS AND DISCUSSION 38 4.1 Determine the viscosity of a silver resinate mixture - coconut oil 38 4.2 Determination of silver content in silver resinate mixture 39 4.2.1 Determined by FTIR method 39 4.2.2 Determined by XRD method 40 4.3 Determination of silver size and elemental composition in coated and calcined glass samples 42 4.3.1 Determined by XRD method 42 4.3.2 Observe the surface of SEM glass 42 4.3.3 Analysis of elemental composition of EDX glass 44 4.4 Evaluate the results of silver nano coatingon glass by uv - VIS method 44 4.5 Assess the antibacterial properties of nano-silver on representative bacteria types 45 4.6 General discussion 48 CHAPTER 5: CONCLUSIONS AND RECOMMENDATIONS 50 Conclusion 50 Request 51 REFERENCES 52 iv LIST OF TABLE Table 2.1 Table 3.1: Table 3.2: Table 3.3: Table 4.1: Table 4.2: Number of silver atoms in a unit of volume Chemicals used in research 28 Instruments used in the process of research 29 Equipment in the research process 30 Results of viscosity measurement 38 Antibacterial test results of glass (spin coating, dip coating) 46 LIST OF FIGURES Figure 2.1 silver element (Ag) Figure 2.2 Antiseptic mechanism of nano silver Figure 2.3: Application of silver nano in household products 11 Figure 2.4: Application of silver nano in agriculture 12 Figure 2.5: Nano Silver water filter core 12 Figure 2.6: Application of silver nano in textiles 13 Figure 2.7: Coconut essential oil 14 Figure 2.9: Technology diagram of coconut oil production by hot pressing - hot pressing method 16 Figure 2.10 Diagram of coconut oil production technology by centrifugal method 17 Figure 2.11: Principle of method of evaporation 19 Figure 2.12: Principle of sputtering process 20 Figure 2.13: Evolution of Sol - gel process 23 Figure 2.14: Some methods of Sol - gel membrane coating 23 Figure 2.15: Dip - coating process 24 Figure 2.16: Steps of the Spin - coating process 25 Figure 3.1: Process diagram of manufacturing antibacterial glass 32 Figure 3.2 Chart of experimental assessment of results 35 Figure 4.1: FT-IR spectrum of (a) NaOH IM; (b) coconut oil, (c) AgNO3 and (d) silver resinate 40 Figure 4.2: XRD result of Silver resinate sample after drying 105°C/18h 41 Figure 4.3: XRD result of Silver Resinate sample after heating 500°C / 3h 41 Figure 4.4: XRD spectrum of (a) uncoated glass sample; (b) sample of dip coated glass, calcined at 500°C/3 hours; and (c) Spinning coated glass sample, calcined at 500oC/3 hours 42 Figure 4.5: SEM images of dipped and spin coated glass samples at different magnifications 43 Figure 4.6: Results of EDX surface dip coated glasses 44 v Figure 4.7: Results of EDX spin coating glass surfaces 44 Figure 4.8: Results of transmission of two glass samples 45 LIST OF ABBREVIATIONS FT-IR X-XDR Fourrier Transformation Insfrared X-ray diffraction SEM Scanning Electron Microscope EDX Energy-dispersive X-ray spectroscopy UV-VIS Ultraviolet-Visible spectrophotometer vi CHAPTER 1: INTRODUCTION 1.1 The necessity of the topic Silver is the oldest known natural antibacterial agent Silver and its compounds exhibit toxicity to bacteria, viruses, algae and fungi Silver does not show toxicity to humans, non-toxic, non-irritant Scientific fact has proved that silver ions can destroy more than 650 strains of microorganisms, 260 types of harmful germs that cause disease and also gram-negative and positive bacteria Silver inhibits the metabolism of respiration and the transport of substances through microbial cell membranes Silver has the ability to destroy the enzyme that transports the nutrients of bacterial cells, weakens membranes, cell walls and cytoplasm, disrupts metabolism, leading to bacterial destruction Silver Nano has the potential to be applied in many fields such as agriculture, industry and health to create many new and high quality products, bringing socio-economic efficiency The application of nano silver in health, life and manufacturing will also help protect human health, minimize environmental pollution and develop production In medical use, silver nano solution is used: Covering artificial bone details, treating respiratory tract infections, treating urogenital infections, bandages for wounds such as bums, necrotic ulcers From the advantages of nano silver as well as the usefulness, the difference of the method to create silver resinate from coconut oil is extremely necessary with the goal of going beyond creating an environmentally friendly product Users can take advantage of available raw materials in Vietnam at low cost With the goal of creating a sterile environment for hospitals, and food processing facilities researching silver nano-coated glass materials with coconut oil solvents A type of organic substance very popular in Vietnam 1.2 Objectives of the study > General goal Development of silver nano coating materials to apply in practice, to improve the environment, prevent harmful bacteria to humans > Specific objectives Initial research on manufacturing antibacterial glass by coating nano silver with coconut oil solvents 1.3 Object of research - Scope of research 1.3.1 Research subjects Nano silver Glass Coconut oil 1.3.2 Research scope > Space - To be accomplished with the support of the following laboratories: - Solid waste research and intensive research laboratory of the Institute of Science, Technology and Environment Management, Industrial University of Ho Chi Minh City (12 Nguyen Van Bao, Ward 4, Go Vap District, Ho Chi Minh City) - Silicate laboratory of Ho Chi Minh City University of Technology (268 Ly Thuong Kiet, Ward 14, District 10, Ho Chi Minh City) - Center for BioScience and Biotechnology at VNUHCM-University of Science (227 Nguyen Van Cu, Ward 4, District 5, Ho Chi Minh City) > Scale - Laboratory Based on the results of XRD analysis, it shows that the silver resinate produced after drying does not have the appearance of silver molecules but the appearance of volatile organic substances Resinate silver after calcination at 500°C, the presence of Ag + ions exists in nano form and there is no organic matter 4.3 Determination of silver size and elemental composition in coated and calcined glass samples 4.3.1 Determined by XRD method Figure 4.4 shows the XRD spectrum results of (a) uncoated glass samples, (b) sample of dip coated glass, calcined at 500°C/3 hours; and (c) Spinning coated glass sample, calcined at 500°C/3 hours, respectively as follows: (c) Spinning coated glass sample, calcined at 500°C/3 hours (b) Dip coating glass sample, calcined at 5OO°C/3 hours (a) Uncoated glass sample 2theta (degree) Figure 4.4: XRD spectrum of (a) uncoated glass sample; (b) sample of dip coated glass, calcined at 500°C/3 hours; and (c) Spinning coated glass sample, calcined at 500°C/3 hours Discussion: According to the chart, we see: - All three XRD spectra not appear crystals of Ag or AgNCh, indicating that AgNCh salt has been completely dissolved, existing in amorphous form 42 - The amorphous structure of Ag together with the amorphous structure of the glass substrate will help increase the ability to diffuse Ag ions into the glass substrate when heated at 500°C 4.3.2 Observe the surface of SEM glass SEM results of the surface of dipped and spin coated glass samples at different magnifications (Figure 4.5), as follows: Figure 4.5: SEM images of dipped and spin coated glass samples at different magnifications Discuss: - Based on analysis by SEM method we can see the formation of crystals on the glass surface - The spinning coating has a larger crystal surface than the dipping coating - The spinning coating has silver crystals on the surface of the glass more than the dipping coating 43 4.3.3 Analysis of elemental composition of EDX glass EDX results of cross section of two samples of embedded lamination glass (Figure 4.6) , rotating coating (Figure 4.7) as follows: Figure 4.6: Results of EDX surface dip coated glasses O-K Si-K Ag-L Figure 4.7: Results of EDX spin coating glass surfaces Discussion: The EDX method determines the coating thickness and composition of glass elements after coating with silver nano Based on the analysis results, we see that both glass samples have silver molecules However, the silver molecular density on the spinning glass sample is higher than the silver molecular density on dipping glass sample 4.4 Evaluate the results of silver nano coating on glass by uv - VIS method The results of UV-VIS transmission analysis of two glass samples (spin coating, dip coating) after calcined at 500°C / 3h (Figure 4.8) are as follows: 44 110 (a) Uncoated glass sample o (b) Dip coating glass sample, calcine at 500 C/3 hours % o Transmittance / (c) Spinning coated glass sample, calcined at 500 C/3 houi Wavelength / nm Figure 4.8: Results of transmission of two glass samples Discussion: UV-VIS method measures the transmittance of a material after silver nano coating Based on the chart we see no difference between dipping and spinning overlay At a wavelength of 420 nm is the characteristic absorption point for silver From 500 nm and above most light is transmitted, uv rays are filtered Therefore, we can conclude that both embedded and rotating glass samples are uv resistant 4.5 Assess the antibacterial properties of nano-silver on representative bacteria types In recent years, the causative agent of nosocomial infections is diverse, but mainly Gram-negative bacteria - Gram-negative bacteria: Echerichia coli, p aeruginosa, Salmonella, Acinetobacter are multi-antibiotic resistant bacteria • Salmonella: often causes infectious diseases, food poisoning, typhoid • Escherichia Coli: causes urinary tract and surgical site superinfection • Pseudomonas aeruginosa: has properties of resistance to antiseptics and antibiotics; often cause disease in patients with weakened resistance, malignancies, 45 - Gram-positive bacteria: account for about 20% of nosocomial infections such as s aureus, Bacillus, • Staphylococcus aureus is capable of causing many different diseases such as skin infections, bacteremia, pneumonia In this thesis, five strains of bacteria were selected Five representative standard strains of bacteria (E coli, s.aureus, p aeruginosa, S.Typhimurium, B.cereus) provided by The Center for Biosciences and Biotechnology, University of Science in HCM City The results of assessing the antibacterial properties of glass samples (spin coating, dip coating, uncoated silver resinate) are shown in Table 4.2: Table 4.2: Antibacterial test results of glass (spin coating, dip coating) Bacterial Bacterial concentration concentration No Sample Test criteria Test method before after coating coating (Oh) (24h) (CFU/ml) (CFU/ml) 4,2 X 106 Not detected Antibacterial ability TCVN Escherichia coll 9064:2012 Samples Antibacterial ability of 2,1 X 106 1,8 X 103 Bacillus subtilis TCVN 9064:2012 TCVN 9064:2012 1,6 X 106 3,5 X 104 TCVN 9064:2012 3,2 X 106 Not detected spinning coating Antibacterial ability glass Staphylococcus aureus Antibacterial ability 46 Pseudomonas aeruginosa Antibacterial ability Salmonella TCVN 9064:2012 1,8 xio6 2,6 X 102 TCVN 9064:2012 4,2 X 106 1,9 xio7 TCVN 9064:2012 2,1 X 106 2,7 X 107 TCVN 9064:2012 1,6 X 106 3,4 X 107 TCVN 9064:2012 3,2 X 106 5,6 X 107 TCVN 9064:2012 1,8 X 106 1,2 X 107 Typhimurium Antibacterial ability Escherichia coli Antibacterial ability Bacillus subtilis Antibacterial ability Uncoated Staphylococcus glass aureus samples Antibacterial ability Pseudomonas aeruginosa Antibacterial ability Salmonella Typhimurium Source: Antimicrobial test results at the Center for Bioscience and Biotechnology, University of Science, VNU HCMC Note: TCVN 9064:2012 National Standards Paints and Plastics - Measurement of antibacterial activity on surfaces Discussion: Based on the analysis results table, we see: - Uncoated glass samples after 24h all types of bacteria are growing well in large numbers 47 - Samples of spinning coating glass is resistant to all type of Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa, Salmonella Typhimurium, Bacillus cereus Particularly with two type of Escherichia coli, Pseudomonas aeruginosa were completely destroyed - Samples of dipping coating glass does not have complete antibacterial but it can inhibit the growth of types of bacteria 4.6 General discussion Through the analysis results obtained, show us: - Coconut oil is suitable as a solvent to create coating silver resinate - Based on the EDX results and the antibacterial test results, the rotational coating method has better results than the dip coating method - Compared to the topic "Fabricating antimicrobial glass using nano silver" by students of Institute of Science, Technology and Environment in 2018, this report has the following differences: + Determining the exact ratio of coconut oil solvent and silver resinate is Igam resinate for 20ml of coconut oil + Compared to the screen printing method (the topic of "Fabricating anti-bacterial glass using nano silver" in 2018), the rotating and dipping coating method is more advantageous and easier to apply for industry + Compared with the antibacterial results of the project "Manufacturing and testing antibacterial glass using silver nanoparticles" in 2018, selecting bacteria types (Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa) achieved very good resistance results with two type Escherichia coli and Pseudomonas aeruginosa, weak resistant Staphylococcus aureus With the theme of "Manufacturing antibacterial glassware using nano silver" in 2019, the project chose to test on types of bacteria: Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa, 48 Salmonella Typhimurium, Bacillus cereus., the project achieved 100% resistance to type of Escherichia coli and Pseudomonas aeruginosa, and type of Staphylococcus aureus, Salmonella Typhimurium, Bacillus cereus achieved weak resistance 49 CHAPTER 5: CONCLUSIONS AND RECOMMENDATIONS Conclusion After the research and analysis results, some conclusions can be drawn as follows: - Coconut oil is suitable as a carrier to create silver resinate coating - Through infrared analysis results FT-IR evaluates the physical and chemical characteristics of the solution Show that silver reacts with saponification and produces RCOOAg - Pass the test results viscosity of coating solution The ratio of 1:20 (with gram of solid resinate: 20 ml of coconut oil) is the optimal viscosity ratio And the 1:20 ratio was chosen as the ratio to conduct silver coating on Resinate - Through XRD analysis results, it shows that silver resinate after calcination at 500°C has created Ag+ ions exist in nano form, high practical applications - SEM analysis results show that glass samples after firing in both spin and dip coating methods have nano silver on the surface - Through the results of EDX analysis, it shows that glass samples after firing in both coating and dipping methods contain silver elements Nano-silver should have gone inside the structure of the crystal glass, not just on the surface of the glass - In addition, EDX results show that the rotating coating method is more advantageous because the silver density on the rotating glass is higher and more uniformly distributed - UV-VIS analysis results show that the transmittance is reduced compared to the uncoated sample up to 80%, at 420 nm is the typical absorption wavelength of silver Prove that the coating is silver and highly uv resistant - Through the antibacterial and EDX results, it is shown that the spinning coating method is more advantageous because the silver density on the spinning glass is higher and more evenly distributed So spin coating glass has better antibacterial properties than dip coating glass 50 At the end of the research process, it was successfully created coconut oil soap and silver resinate coating Initial development of antibacterial glass, prevention, and resistance to five specific bacteria in the health sector is (Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa, Salmonella Typhimurium, Bacillus cereus) This has great significance in terms of the environment and especially the hospital environment Request - Should be applied in hospitals, clinics needing environment free of bacteria Through practice, it is also possible to apply antibacterial glass extension to food, industry, agricultural and aquatic product processing industries to improve the quality of food materials - Survey to find out some other solvents instead of coconut oil but still retain the commercial value of its countiy Such as replacing coconut oil with peanut oil, cashew oil, palm oil, canola oil - Subsequent studies can provide optimal coating methods for glass to achieve a uniform and beautiful coating - Research and test the antibacterial level of silver-coated glass plates on many different types of bacteria - Can increase the original silver content to achieve better antibacterial results 51 REFERENCES Vietnamese [1] Do Quang Minh (2015), "Glass production technique", National University Press, Ho Chi Minh City [2] Hoang Van Duc, Coconut tree, Hanoi Agricultural Publishing House, 1991 [3] Ngo Quoc Buu, Nguyen Hoai Chau, Tran Thi Ngoc Dung, Nguyen Gia Tien, (2011): Studies on manufacturing of topical wound dressings based on nanosilver produced by aqueous molecular solution method Journal of Experimental Nanoscience, Vol 6, No 4, pp 409 - 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