THAI NGUYEN UNIVERSITY UNIVERSITY OF AGRICULTURE AND FORESTRY LE THUY LINH ANTIMICROBIAL ACTIVITY OF ESCHERICHIA COLI USING N-TiO2- PMMA COMPOSITE BACHELOR THESIS Study Mode : Full-time Major: Environmental Science and Management Faculty: International Programs Office Batch : 2013-2017 Thai Nguyen, 2017 n n Thai Nguyen University of Agriculture and Forestry Degree Program Bachelor of Environmental Science and Management Student Name Le Thuy Linh Student ID DTN1353110171 Thesis Title Antimicrobial activity of E. coli using N-TiO2-PMMA Composite Assoc. Nguyen The Hung Supervisor Prof. Yao Tung-Lin Abstract: Titanium dioxide (TiO2) is a semiconductor and photocatalyst in the decomposition and disinfection of bacteria.
In particular, TiO2 were work under ultraviolet light and visible light. It also had capable of producing a pair of electron holes due to exposure to ultraviolet and visible light. From that Titanium dioxide can be used in combination with nitrogen (Nitrogen doped titanium dioxide) to create a substance that inhibits the activity and growth of bacteria in which clarify ability to inactivate, especially bacterial Escherichia Coli. This experiment would use the dip- coating method with antibacterial by Nitrogen doped titanium dioxide (N-TiO2) and then saw the disinfection activity of E.coli for 24 hours by N-TiO2 0.
During experiment took polymethyl methacrylate (PMMA) pieces dip-coating with N- TiO2 and put PMMA under visible light with the amount 990 to 1010 lux. In all experiments process, E.coli concentration was dilution by 104 and 105 CFU/ mL. The results of the experiment showed that E.coli was affected by N-TiO2 antibacterial. The number of growth and decomposition bacteria has a distinct gap when using N- i n TiO2with different percentages.
It would reduce the growth of bacteria and cough complete disinfection around 24 hours. Antibacterial by N-TiO2 has showed as the optimum one to directly active on bacterial. Titanium dioxide, Nitrogen doped titanium dioxide, Keywords Escherichia coli, Polymethyl Methacrylate. Number of Pages 43 Date of Submission 20/09/2017 Supervisor’s signature ii n ACKNOWLEDGMENTS From bottom of my heart, I would like to express my deepest appreciation to all those who provided me the opportunity to complete this research.
First and foremost, I would like to express my sincere gratitude and deep regards to my supervisor: Pro. Yao Tung-Ling of National Chung Hsing University, Taichung, Taiwan, who guided me wholeheartedly when I implemented this research. He is always willing to give suggestions on scientific problems and personal issues. He is very supportive and a good listener.
Under his instruction with patience, knowledge and talent, I’m able to fulfill to my thesis. I also want to express my thanks to Assoc. Nguyen The Hung, the second supervisor, for his supervision, encouragement, advice, and guidance in writing this thesis. In addition, formal thanks should be offered to the Rector of National Chung Hsing University for granting my internship acceptance.
I want to thank all of my colleagues in the ENM ( Environmental Nano Material) Laboratory, Miss. Jing-Hua Tzeng, Mr. Chakkrit Poonpakdee, Miss. Li-Ting Yen, Miss.
Ya-Zhen Huang, Mr. Le Quoc Anh, Miss. Kai-Fen, Mr. Che-Chien, Miss.
Than Thi Nhu Anh. They are very generous and supportive. It was a great pleasure to work with them. I want to express my sincerest appreciation to my parents, my friends and my team for their love and support me everytime.
Thai Nguyen, 20thSeptember, 2017 Student Le Thuy Linh iii n TABLE OF CONTENT CHAPTER I: INTRODUCTION .2Objective of the study .3 CHAPTER II: Literiature Review .3 Visible light responsive .8 CHAPTER III: Material & methods.1 Material and equipment .2 Dip-coating of PMMA .1 Dosage bacteria without N-TiO2 .16 CHAPTER IV: Result &Discussion .1 Control experiment to E.2 N-TiO2 dosage effect .3 Compare N-TiO2 dosage effect .4 Compare control and N-TiO2 dosage effect .41 iv n LIST OF TABLES Table 1: The bacteria used in experiment…………………………………………….11 Table 2: Some of nutrient used in experiment……………………………………….11 Table 3: Some of chemical used in experiment………………………………………12 Table 4: Some of equipments used in experiment ……………………………………13 v n LIST OF FIGURES Figure 1: Bacterial Escherichia coli ( E.4 Figure 2: The Polymethyl methacrylate plastic ( PMMA)……………………………8 Figure 3: Flow chart of work…………………………………………………………10 Figure 4:Show the Dip-coating process…………………………………………….15 Figure 5:Dosage effect without N-TiO2…………………………………………….19 Figure 6: Another control experiment……………………………………………….5% dosage effect with visible light intensity 2.2x10-4 lux: a, survival of bacteria ; b. amount of bacteria………………………………………….5% dosage effect with visible light intensity 3.09x10-4 lux: a, survival of bacteria ; b. amount of bacteria………………………………………….5% dosage effect with visible light intensity 1019 lux: a, survival of bacteria; b. amount of bacteria…………………………………………………….23 Figure 10:N -TiO2 1% dosage effect with visible light intensity 2.91x10-4-1006 lux: a, survival or bacterial; b, amount of bacterial………………………………………….25 Figure 11:N-TiO2 1% dosage effect with visible light intensity 2.95x10-4, 1000 lux in Box A: a, survival or bacterial; b, amount of bacterial……………………………….26 Figure 12:N-TiO2 1% dosage effect with visible light intensity 2.95x10-4, 1000 lux in Box B: a, survival or bacterial; b, amount of bacterial……………………………….27 vi n Figure 13:N-TiO2 1% dosage effect with visible light intensity 1004 lux : a, survival or bacterial; b, amount of bacterial……………………………………………………28 Figure 14:N-TiO2 1% dosage effect with visible light intensity 1007 lux: a, survival or bacterial; b, amount of bacterial………………………………………………….29 Figure 15:N-TiO2 2% dosage effect with visible light intensity 2.96x10-4- 1007 lux in Box A: a, survival or bacterial; b, amount of bacterial……………………………….30 Figure 16: N-TiO2 2% dosage effect with visible light intensity 2.95x10-4-1000 lux in Box B: a, survival or bacterial; b, amount of bacterial……………………………….31 Figure 17: N-TiO2 2% dosage effect with visible light intensity 1005lux in Box A: a, survival or bacterial; b, amount of bacterial………………………………………….32 Figure 18: N-TiO2 2% dosage effect with visible light intensity 1005 lux in Box A: a, survival or bacterial; b, amount of bacterial……………………………………….33 Figure 19: Compare N-TiO2 dosage effect: a, survival or bacterial; b, amount of bacterial……………………………………………………………………………….35 Figure 20: N-TiO2 dosage effect to S.aureus: a, survival or bacterial; b, amount of bacterial……………………………………………………………………………….36 vii n n CHAPTER I: INTRODUCTION 1.1 Introduction Organizations and governments around the world especially interested in the issues of human health.
In particular, infections and microbial contamination are one of the most prevalent diseases in society which government and people take care. Social development along with the development of medicine and biotechnology should be able to research and find the release minimize infectious diseases and infections. Follow the World Health Organization (WHO), medical infections can occur anywhere in the world. In particular, all developed countries and poor countries around the world are affected by microbes and bacteria.
According to the statistics released, there are 8.7% of about 1, 4 million people infected in 55 health facilities in 14 countries every year. The number is not small, the consequences of the infection are very serious, it can lead to death, prolonged work time, increased use of antibiotics and the cost of treating the disease. Currently, in the world has emerged resistant bacteria to most antibiotics, also known as super-resistant bacteria. Antibiotics were not long effective and prevent bacteria as it will be dangerous and effect directly to people healthy.
In fact, Vietnam has the highest bacteria of antibiotic resistant most clinics were facing the speed of spreading bacteria resistant to many antibiotics, the level and rate of drug resistance is increasing at an alarming rate. According to the statistics of Bach Mai Hospital in southern of Vietnam, the rate of E.coli (enterobacteria) antibiotic resistance was up to 74.6%;the resistance rate of bacteria causing infection K.pneumoniae up to nearly 60%; A.baumannii bacteria (infection of the hospital) has the rates antibiotic resistance 1 n of over 90% and the carbapenem antibiotic group, the strongest antibiotic group currently has a 50% rate, especially gram-negative bacteria bearing resistance genes such as Beta lactamase. Thus, finding a new alternative to the use of antibiotics in the world as well as Vietnam is a necessity. From the statistics above to find new ways to prevent the infection of bacteria using semiconductor photocatalyst.
Used a catalyst cause it accelerates a chemical reaction without being consumed as a reactant. As know as photocatalysis is considered accelerated photoreaction by the presence of a catalyst and Titanium dioxide (TiO2) is one of the best photocatalysts because TiO2 has a high chemical stability when exposed to inorganic and basic compounds, non-toxic properties, low cost and high oxidation capacity. In case, TiO2 had using in many applications in a wide variety of applications, the properties of TiO2 can be cleaned, decomposed in air and especially sterilized. This chemical great in preventing the spread of infection in the world.(Castellote & Bengtsson, 2011) In our life, infected quite dangerous for our healthy, it also is common cause of death.coli is a bacteria causes primarily infected in humans.
To solve and solution that problem trying to research and learn new chemical from photocatalysts. That is N-TiO2 (Nitrogen doped titanium dioxide) while PMMA (methyl methacrylate plastic) will dip-coating with N-TiO2 and improving old methods to use more efficient.2 Objective of the study • To synthesis visible light- responsive N-TiO2- PMMA composite. • To investigate the key parameters of photodisinfection using N-TiO2- PMMA. • To study the kinetic of photodisinfection for bacteria.
• To clarify the mechanisms of photodisinfection. 3 n CHAPTER II LITERATURE REVIEW 2.coli is one of the bacteria that causes diseases of intestinal tract of humans and animals. coli usually parasitic in the large intestine.coli can easily be found in the environment of facal, warmth and can survive for a long time.coli also have biochemical characteristics as sugar fermentation, vaporization and denitrification of nitrate become nitrite in humans and animals ( Donnenberg MS, 2010). Figure 1: Bacterial Escherichia coli ( E.coli) In addition, E.coli belongs to the family Enterobacteriaceae, similar with Escherichia.
On the morphology of this bacteria, it is bacillus and gram negative with no stomach and tissue.coli external structure, it had fur around. The typical size of an E.coli is about 0.5 um to 2 or 3 um, depending on the development of each individual. 4 n During the experiment used nutrient agar to grow E. Bacterial usually grow and development at temperatures about 15 to 40 degrees.
But the most suitable temperature for grow up E.coli is 37 degrees, which similar to the body temperature. PH levels generally range from 6. After 24 hours culturing in Nutriant Agar, E.coli form round peanut bacteria and white color (about 2-3mm).2 Photocatalysis Catalyst is a chemical that accelerates a chemical reaction without losing the reagent. Therefore, to reduce the amount of enthalpy triggered by the free reaction, it need a compound and it is called a catalyst.
Thus, photocatalysis is defined as a catalyst in the process of accelerating photoreaction(Castellote & Bengtsson, 2011).Photocatalysis is the process of converting solar energy into chemical energy. Also chemically converted through metal oxide nanostructures. Including metal such as TiO2, ZnO, CeO2 and SnO2, and there have great potential for oxidation as well as catalysts for organic pollutants. TiO2 is almost used for high stability as well as photocatalytic activity, non-toxic and biocompatibility.(Sajid Ali Ansari, Khan, Ansari, & Cho, 2016) Titanium dioxide (TiO2) is the most widely used white pigment and also high brightness and a very high refractive index.
The light passes through the crystal slowly and its path is substantially altered compared to air. Titanium dioxide (TiO2) photocatalyst can be applied in many different fields. It had advantage of high chemical stability , exposure to other compounds acidic, non- toxic, low cost and highly oxidizable.TiO2 photocatalysis is almost used in products and applications for the environment and 5 n energy. They used in self-cleaning surfaces, air and water filtration systems, disinfection.
And also an important factor in the evolution of hydrogen and photoelectric conversion.3 Visible light responsive 2.1 What is Visible light In fact, most human eyes can see visible light as the wavelengths and visible light also is a form of electromagnetic (EM) radiation. At different wavelengths and frequencies, EM radiation can transmitted through waves or particles as the electromagnetic spectrum.