Optimization of multifunctional nanoparticles for biosensor application

VIETNAM NATIONAL UNIVERSITY, HANOI VIETNAM JAPAN UNIVERSITY LO TUAN SON OPTIMIZATION OF MULTIFUNCTIONAL NANOPARTICLES FOR BIOSENSOR APPLICATION MASTER'S THESIS …………………………… MASTER OF NANOTECHNOLOGY Hanoi, 2019 VIETNAM NATIONAL UNIVERSITY, HANOI VIETNAM JAPAN UNIVERSITY LO TUAN SON OPTIMIZATION OF MULTIFUNCTIONAL NANOPARTICLES FOR BIOSENSOR APPLICATION MAJOR: Nanotechnology CODE: Pilot RESEARCH SUPERVISOR: Associate Prof Dr NGUYEN HOANG NAM Hanoi, 2019 ACKNOWLEDGEMENT At first, I would like to express my acknowledgement to my supervisor, Associate Prof Dr Nguyen Hoang Nam, for his advice, instructions, for supplying researching environment in laboratory and for giving motivation during my research I would like to express my gratefulness to Professor Tamiya, my supervisor in Osaka during this internship for supplying working environment, all of group meeting, seminars, discussion and suggestion for my research and my future plans I sincerely thank all professors, staff, and friends in Vietnam Japan University and VNU - University of Science for supplying me the best condition for my research Hanoi, 10th, June, 2019 TABLE OF CONTENT LIST OF FIGURES LIST OF TABLES LIST OF ABBREVIATION CHAPTER 1: GENERAL INTRODUCTION 1.1 Targeted nanoparticles and biosensors for disease therapy in biomedicine1 1.2 Multi - functional magnetite-silica-amine-gold nanoparticles (MSAANPs) 1.2.1 Magnetite nanoparticles (MNPs) 1.2.1.1 Introduction 1.2.1.2 Magnetic property 1.2.1.3 Synthesis of magnetite nanoparticles .5 a Co-precipitation method b Thermal decomposition of iron organic precursor method 1.2.2 Core-shell structure magnetite-silica nanoparticles 1.1.2.1 Roles of silica shell 1.1.2.2 Coating silica shell on magnetite nanoparticles a Stöber method b Inverse microemulsion 10 1.2.3 Multifunctional magnetite-silica nanoparticles 11 1.2.3.1 Introduction 11 1.1.3.2 Application of multifunctional magnetite - silica nanoparticles 12 a Drug delivery system .12 b Hyperthermia 13 c MRI imaging 14 1.3 Multi - functional MSAANPs applied for biosensor 14 1.4 Investigation and optimization of experimental procedure 16 1.4.1 Synthesis of MNPs 16 1.4.2 Synthesis of MSNPs 17 CHAPTER 2: PRINCIPLES OF MEASUREMENT METHODS 19 2.1 Dynamic Light Scattering (DLS) measurement .19 2.2 Zeta Potential measurement 20 2.3 Transmission Electron Microscope (TEM) measurement 21 2.4 Ultraviolet - visible spectroscopy (UV-VIS) 22 2.5 X-ray Diffraction (XRD) 23 2.6 Vibrating sample Magnetometer (VSM) 23 2.7 Fourier Transform - Infrared Spectroscopy (FT-IR) 24 CHAPTER 3: EXPERIMENTAL PROCEDURE 26 3.1 Synthesis and characterization of MNPs, MSNPs, MSANPs and MSAANPs 26 3.1.1 Magnetite nanoparticles (MNPs) 26 3.1.2 Magnetite/silica nanoparticles (MSNPs) 26 3.1.3 Synthesis of magnetite-silica nanoparticles functionalized by amine groups (MSANPs) 27 3.1.4 Magnetite/silica/amine/gold nanoparticles (MSAANPs) 28 3.2 Investigation and optimization of synthesis procedure 28 3.2.1 Investigation of effect of pH on PSD and zeta potential of MNPs 28 3.2.2 Investigation of effect of surfactant on stability of MNPs 29 3.2.3 Investigation of effect of temperature on silica coating reaction 29 3.2.4 Investigation of effect of TEOS on magnetic properties of MNPs in silica coating reaction 30 3.2.5 Investigation of mechanism of silica coating reaction 30 CHAPTER 4: RESULTS AND DISCUSSION 31 4.1 Characterization of MNPs, MSNPs, MSANPs and MSAANPs 31 4.1.1 TEM and DLS results 31 4.1.2 UV-VIS results 33 4.1.3 FT-IR results 34 4.1.4 VSM results 37 4.1.5 XRD results 39 4.2 Investigation and optimization of experimental procedure 42 4.2.1 Effect of pH on stability of MNPs 42 4.2.2 Effect of surfactant on preventing aggregation of MNPs during silica coating reaction 45 4.2.3 Effect of temperature on silica coating reaction 47 4.2.4 Effect of silica precursor on the magnetic properties of magnetite core 48 4.2.5 Effect of silica precursor on the mechanism of silica coating reaction 51 CONCLUSION 55 FUTURE PLAN 56 REFERENCES .57 LIST OF FIGURES Figure 1.1 Some application of nanoparticles as targeted agent in medical diagnosis Figure 1.2 Working principles of biosensor using combined CCD camera and fluorescence .2 Figure 1.3 Working principle of biosensor measuring the change in electrical impedance Figure 1.4 Crystal structure of magnetite Figure 1.5 Vibrating sample Magnetometer (VSM) spectrum of MNPs proves their superparamagnetic property Figure 1.6 Chemical formula of tetraethyl orthosilicate Figure 1.7 Possible processes in silica coating reaction Figure 1.8 Competitive reactions between silica growing on silica nanoparticles and silica seeds 10 Figure 1.9 Synthesis of MNPs by inverse microemulsion method 11 Figure 1.10 Some branch of functionalizing silica layer on magnetite - silica nanoparticles 12 Figure 1.11 Principle of hyperthermia method using MNPs 13 Figure 1.12 MRI images of human brain without using (left) and using (right) MNPs 14 Figure 1.13 Structure of magnetite - silica - amine - gold nanoparticles 15 Figure 1.14 Procedure of synthesizing MSAANPs 15 Figure 1.15 Criteria of MSAANPs needed to be optimized in this research.18 Figure 2.1 Working principles of DLS measurement 19 Figure 2.2 Description of zeta potential 20 Figure 2.3 Instrumental components of TEM 21 Figure 2.4 Instrumental components of UV-VIS measurement 23 Figure 2.5 Working components of VSM measurement 24 Figure 3.1 Chemical formula of PVP 26 Figure 3.2 Chemical formula of APTES 28 Figure 4.1 (left) TEM image of magnetite nanoparticles .31 Figure 4.2 (right) Particles size distribution of magnetite nanoparticles calculated from TEM measurement 31 Figure 4.3 TEM image of magnetite-silica nanoparticles 31 Figure 4.4 TEM image of MNAANPs 32 Figure 4.5 Particles size distribution (PSD) of MNPs, MSNPs, MSANPs and MSAANPs 33 Figure 4.6 UV-VIS spectra of MNPs, MSNPs (sample MS5) and MSAANPs34 Figure 4.7 FT-IR spectra of MNPs, MSNPs and MSANPs 35 Figure 4.8 VSM spectra of MNPs and MSNPs (sample MS4) 37 Figure 4.9 VSM spectra of samples MNPs, MS6 and MSAANPs (1000/H versus Ms) 38 Figure 4.10 XRD spectra of MNPs and MSAANPs 39 Figure 4.11 PSD and zeta potential of MNPs under different pH 42 Figure 4.12 Sedimentation of MNPs under different pH .43 Figure 4.13 Effect of sodium citrate on sedimentation of MNPs 44 Figure 4.14 Description of PVP playing a role on the stabilization of MNPs45 Figure 4.15 PSD and zeta - potential of MNPs under different concentration of PVP 46 Figure 4.16 Sedimentation experiment of MNPs under different concentration of PVP 47 Figure 4.17 TEM images of (a): sample MS5 and (b): sample MS5.1 47 Figure 4.18 DLS results of (a): sample MS5 and (b): sample MS5.1 48 Figure 4.19 VSM results of sample MNPs, MS1, MS2, MS3, MS4 and MS549 Figure 4.20 Hydrodynamic diameter of MNPs during silica coating reaction51 Figure 4.21 The change (Δd) of hydrodynamic diameter of sample MNPs, MS4, MS5, MS6, MS7 during silica coating reaction 52 Figure 4.22 DLS spectra of sample MS4, MS5 MS6 and MS7 after 24h during silica coating reaction 53 LIST OF TABLES Table 3.1 Reacting condition from sample MS1 to MS7 27 Table 4.1 Positions and corresponding type of vibration of MNPs, MSNPs and MSANPs 36 Table 4.2 Magnetic parameters of samples MNP, MS6 and MSAANPs calculated from their VSM spectra 39 Table 4.3 Position of diffraction peaks of magnetite in sample MNPs and their crystal parameters 41 Table 4.4 Position of diffraction peaks of gold nanoparticles in sample MSAANPs and their crystal parameters 41 Table 4.5 Comparison between some magnetic parameters of sample MNPs, MS1, MS2, MS3, MS4 and MS5 50 Table 4.6 Efficiency of silica coating of sample MS4, MS5 and MS7 .54 LIST OF ABBREVIATION Abbreviation Description APTES (3-Amino propyl) Triothoxysilane DLS Polyvinyl pyrrolidone FT-IR Tetraethyl orthosilicate MNPs Magnetite nanoparticles MSNPs Magnetite - silica nanoparticles MSANPs Magnetite - silica - amine nanoparticles MSAANPs Magnetite - silica - amine - gold nanoparticles PSD Particles size distribution PVP Poly vinylpyrrolidone TEM Transmission electron microscope TEOS Tetraethyl orthosilicate UV -VIS Ultra violet - visible light VSM Vibrating sample magnetization XRD X-ray diffraction Table 4.5 Comparison between some magnetic parameters of sample MNPs, MS1, MS2, MS3, MS4 and MS5 Amount of Sample TEOS/100 mg Ms (emu/g) Mr (emu/g) Hc (Oe) MNPs (μL) MNPs 58.1 12.21 MS1 100 63.1 1.72 25.73 MS2 200 55.9 12.21 MS3 500 51.5 0.83 8.82 MS4 1000 47.7 0.42 6.19 MS5 2000 38.6 0.21 4.18 Surprisingly, the saturated magnetization value of sample MS1 is 63.1 emu/g, about 10 percent bigger than sample MNPs (58.1 emu/g) The value of coercivity (Hc) and saturation remanence is also higher than MNPs sample, whereas these values decrease as the amount of TEOS increase from sample MS2 to MS5 This result can be explained by the aggregation of MNPs during silica coating reaction Since the amount of TEOS using in sample MS1 is very small in compared with amount of used MNPs, the formed silica layer was not sufficient to cover all the surface of MNPs Therefore, the surface energy of MS1 was still high and aggregation can occur after washing product This aggregation have a possibility to combine crystal structures of single MNPs to bigger one As a consequence, the saturated magnetization of sample MS1 increase as the size of magnetite core increase due to aggregation [37] 50 4.2.5 Effect of silica precursor on the mechanism of silica coating reaction Figure 4.20 Hydrodynamic diameter of MNPs during silica coating reaction Figure 4.20 showed the hydrodynamic diameter of MNPs during silica coating reaction It can be seen clearly that the diameter of magnetite cluster reduce during first 30 minutes reaction, then it increased gradually after that It should be noticed that the value 216 nm at time t = is not actual the hydrodynamic diameter of magnetite core but the MNPs and PVP that cover on its surface When kind of surfactant as PVP was added, the hydrodynamic diameter of nanoparticles increase due to its steric effect The decrease of hydrodynamic diameter of magnetite cluster after 30 minutes reacting may indicated that PVP was replaced by silica layer in silica coating reaction On the first hour reacting, the thickness of formed silica layer was not big, therefore it led to the decrease of hydrodynamic diameter of MNPs cluster 51 Figure 4.21 The change (Δd) of hydrodynamic diameter of sample MNPs, MS4, MS5, MS6, MS7 during silica coating reaction The effect and mechanism of TEOS on silica coating reaction was investigated by measuring the change of hydrodynamic diameter of MNPs during coating silica reaction under different concentration of TEOS (figure 4.21) It should be noted that the initial diameters of MNPs cluster were different for each experiment, so that could lead to wrong conclusion when comparing directly their values of diameter Hence, in this case, calculating the change in diameter (∆d) would be better idea It can be seen that, for the first hours of reaction, the increase of diameter of sample MS5, which used mL TEOS per 100 mg of MNPs was always bigger than sample MS4, which used 0.5 mL of TEOS That can be easily explained that the bigger amount of TEOS in MS2 than MS1 led to the bigger rate of silica coating reaction However, after hours reacting, the changes in diameter of magnetite-silica nanoparticles in MS4 are MS5 are quite similar, and after hours reacting, the thickness of silica layer in MS4 was even bigger than MS5 This indicated some unexpected reaction, which did not cover silica on magnetite 52 core, had occurred in higher concentration of TEOS The most possible reaction in this case can be the formation of free silica nanoparticles This reaction can be observed more clearly in the samples MS6 and MS7, which used and mL of TEOS per 100 mg of MNPs respectively The average hydrodynamic diameter of of sample MS7 in the first hours was even still smaller than its initial diameter and is the smallest compared with other samples This indicated the formation of silica seed or small silica nanoparticles that reduce the hydrodynamic diameter of sample The formation of silica nanoparticles in high concentration of TEOS can be proved by the DLS results of these samples after 24 hours reacting, as shown in figure 4.22 DLS spectrum of samples MS6 and MS7 showed the presence of separated peaks The bigger peak represented the MNPs coated by silica, while the peak at 58.8 nm is stand for the silica nanoparticles This silica nanoparticles - peak was not shown in the DLS spectra of sample MS4 and MS5, this indicated that at this concentration of TEOS, the formation of silica nanoparticles did not occur or can be negligible Figure 4.22 DLS spectra of sample MS4, MS5 MS6 and MS7 after 24h during silica coating reaction 53 The yield of coating silica reaction can be calculated simply by converting the thickness of silica layer to the volume of TEOS that underwent hydrolysis and coated on surface of MNPs The results of silica coating efficiency of samples MS4, MS5, MS6 and MS7 are shown in table 4.5 Surprisingly, when the initial amount of TEOS doubled from 0.5 to mL, the actual TEOS coated on the MNPs even decrease 1.8 times, led to the 3.6 times reduction of yield from 80 to 22.04 percent The yield of silica coating continue decreasing to 14.32 and 9.08 percent in sample MS6 and MS7 respectively The actual volume of coated TEOS in these sample are respectively calculated as 0.4, 0.22, 0.286 and 0.454 mL A simple comparison between results of sample MS4 and MS7 shows a surprising conclusion that increasing 10 times amount of TEOS just improves 13.5 percent amount of TEOS that coated on MNPs Base on these results, we can conclude that the formation of silica nanoparticles at high concentration of TEOS reduces the efficiency of silica coating to MNPs due to the competitive reaction of silica growth on silica nanoparticles The ideal amount of TEOS should be used to prevent formation of silica nanoparticles and increasing yield of silica coating reaction is about mL per 100 mg of MNPs Table 4.6 Efficiency of silica coating of sample MS4, MS5 and MS7 Sample Diameter of Amount of MNPs (nm) TEOS/100 mg Diameter Yield of silica after 24 silica coating reaction MNPs (mL) coating (%) MS4 0.5 191.1 80.0 MS5 174.4 22.04 180.9 14.32 195.6 9.08 MS6 MS7 148.1 54 CONCLUSION Magnetite nanoparticles (MNPs), magnetite coated by silica nanoparticles (MSNPs), magnetite-silica functionalized by amine (MSANPs) and magnetite-silica-amine-gold nanoparticles (MSAANPs) were synthesized and characterized by various measurement The TEM, XRD and DLS results ensure the morphology, crystal structure and diameter of these nanoparticles Superparamagnetic properties of all samples were confirmed by VSM measurement The cover of silica layer of MNPs and attachment of amine groups and gold nanoparticles can be proved by results from UV-VIS and FT-IR measurement Some experiments have been performed to investigate and optimize the best condition of these reaction Since MNPs is not stable in basic medium, a steric surfactant such as PVP must be used to prevent its aggregation The ideal concentration of PVP to make MNPs most stable is percent for 100 g of MNPs The silica coating reaction should be proceeded at room temperature The amount of TEOS should be about 0.5 - mL per 100 mg of MNPs to ensure their superparamagnetic property and avoid the formation of free silica nanoparticles during silica coating reaction The investigation using DLS measurement shows that cluster of MNPs tend to partly split up during silica coating reaction The rate of this reaction increase dramatically when increase temperature Free silica nanoparticles tend to be formed in high concentration of TEOS Magnetic property of MNPs tend to increase when using very small amount of TEOS due to its aggregation 55 FUTURE PLAN In this research, MNPs, MSNPs, MSANPs and MSAANPs were synthesized successfully and the experimental procedure of MNPs and MSNPs were optimized MSANPs and MSAANPs also should be optimized in their process to obtain product with suitable size, appreciate amount of amine group and gold nanoparticles Some experiment should be continue proceeding to find out the optimized condition for these syntheses, such as effect of amount of APTES on amount of amine group and ability attaching gold nanoparticles, amount of gold-containing precursor (HAuCl4) to the morphology, size distribution and percentage of gold nanoparticles Some experiment about using other functionalized group and metal nanoparticles, such as carboxylic acid (-COOH) and silver nanoparticles should be considered to be synthesize to compare with the original nanoparticles The second step of this project can be proceed once all experiment procedure in the first step were optimized The final optimized nanoparticles (MSAANPs) was tested for their biocompatibility, toxicity and ability to attach to tumor cells Some parameters in these processes would be considered to re-correct to optimize the attaching of MSAANPs 56 REFERENCES [1] A Donatti, Dario & Ibañez Ruiz, Alberto & Vollet, Dimas (2002) A dissolution and reaction modeling for hydrolysis of TEOS in heterogeneous TEOS-water-HCl mixtures under ultrasound stimulation Ultrasonics sonochemistry 133-8 10.1016/S1350-4177(01)00120-1 [2] Abd Shukor, Syamsul Rizal & Zainal, Nor Ain & Azwana Ab Wab, Hajaratul & Abdul Razak, Khairunisak (2013) Study on the Effect of Synthesis Parameters of Silica Nanoparticles Entrapped with Rifampicin CHEMICAL ENGINEERING TRANSACTIONS 32 2245-2250 10.3303/CET1332375 [3] Barbara A Maher; Imad A M Ahmed; Vassil Karloukovski; Donald A MacLaren; Penelope G Foulds; David Allsop; David M A Mann; Ricardo Torres-Jardón; Lilian Calderon-Garciduenas (2016) "Magnetite pollution nanoparticles in the human brain" (PDF) PNAS 113 (39): 10797–10801 [4] Blaney, Lee (2007) Magnetite (Fe3O4)Properties, synthesis and applications The Lehigh Review 15 33-81 [5] Boistelle, R & Astier, J.P (1988) Crystallization Mechanisms in Solution Journal of Crystal Growth 90 14-30 10.1016/0022-0248(88)90294-1 [6] Brinker, Charles (1988) Hydrolysis and condensation of silicates: Effects on structure Journal of Non-Crystalline Solids 100 31-50 10.1016/0022-3093(88)90005-1 [7] Bui, Thanh & Nu-Cam Ton, Suong & Duong, Anh & Thai Hoa, Tran (2017) Dependence of magnetic responsiveness on particle size of magnetite nanoparticles synthesised by co-precipitation method and solvothermal method Journal of Science: Advanced Materials and Devices 10.1016/j.jsamd.2017.11.002 [8] C.F Chan, Daniel & Kirpotin, Dmitri & Bunn, Paul (1993) Synthesis and Evaluation of Colloidal Magnetic Iron-Oxides for the Site-Specific Radiofrequency Induced Hyperthermia of Cancer Journal of Magnetism and Magnetic Materials 122 374-378 10.1016/0304-8853(93)91113-L 57 [9] Chaki, Sunil & Malek, Tasmira & Chaudhary, Mahesh & Tailor, Jiten & Deshpande, M (2015) Magnetite Fe3O4 nanoparticles synthesis by wet chemical reduction and their characterization Advances in Natural Sciences: Nanoscience and Nanotechnology 10.1088/2043-6262/6/3/035009 [10] Chin, Suk & Pang, Suh & Tan, Ching-Hong (2011) Green Synthesis of Magnetite Nanoparticles (via Thermal Decomposition Method) with Controllable Size and Shape Journal of Materials and Environmental Science [11] Chou, Kan-Sen & Chen, Chen-Chih (2008) The critical conditions for secondary nucleation of silica colloids in a batch Stöber growth process Ceramics International - 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