Surface Plasmon Resonance Characterization of Biodiesel

Surface plasmon resonance (SPR) is a technique to retrieve information on optical properties of biomaterial. Essentially, SPR depends on the optical properties of metal layer and the attached dielectric to the metal layer. It was therefore used in this work as an optical sensing unit in characterizing biodiesel and blend biodiesel for finding the relation of refractive index with concentration of oil in the oil and methanol mixture. This study also includes the novel SPR sensor for detection of corrosion of biodiesel and detection of water in biodiesel and blend biodiesel. To achieve these, two computer programs were written to carry out data acquisition, simulation and analysis of experimental data. These programs are based on matrix methods which were written with matlab software for prism configuration. The fitting process was done by iteratively adjusting the pertinent parameters such as thickness, real and imaginary parts of refractive index, until the lowest sum of the squared error was obtained. By using simulation and experimental data, the effects of sensing layer thickness and variation of wavelength on SPR signals were estimated. Various wavelengths were attempted to induce surface plasmons resonance by using Kretschman scheme. The sensing metal layer was initially sputtered on high index prism in Kretschman configuration. At a fixed sensing layer thickness, the angle of resonance was found to be very sensitive to the characteristics of biodiesel in contact with the sensing gold thin film. Normal grade palm oil biodiesel (NPB) and winter grade palm oil biodiesel (WPB) were initially prepared in tranestrification with NaOH catalyst at 60ºC and 5ºC respectively. The significant difference between NPB and WPB can be found from their dispersion curves. The difference is attributed to the much higher Palmitic acid, 16:0C content in NPB than in WPB. On the other hand, the biodiesel blend was prepared by mixing of Malaysian palm oil biodiesel and Petronas diesel fuel using hand shaking method at room temperature; and the percentage of biodiesel was from 10% to 90% (B10, B20, B30, B40, B50, B60, B70, B80 and B90). A linear relation was discovered between the refractive index and the concentration of palm oil biodiesel . In the case of coconut oil biodiesel it was prepared by mixing the virgin coconut oil and methanol at 63°C. The methyl esters, which contribute in the coconut oil biodiesel, were methyl laurate, methyl myristate and methyl palmitate. The volume ratio (methanol to oil) was found to shift from 9 v/v to 0.12 v/v while the refractive index of the mixture shifted from 1.3426 to 1.4246. Thin Polypyrrole–Chitosan coated on the gold layer was also used to detect 2Zn and2Ni in aqueous solution. The curve of the resonance angle shift against ion concentration fitted well to the Langmuir model

Measurement of copper nanoparticle concentration using surface plasmon resonance

In this work, the concentration of copper nanoparticles in virgin coconut oil were measured using surface plasmon resonance technique, and the gold layer was modified by using Polypyrrole Multi-Walled Carbon Nanotube composite layer. The concentration of nanoparticles and angle of resonance shifted from 0.066 mg/L to 0.71 mg/L and from 64.779° to 64.96°, respectively, and the sensitivity of sensor is about 0.01 mg/L

Surface plasmon resonance sensor for detecting of arsenic in aqueous solution using polypyrrole-chitosan-cobalt ferrite nanoparticles composite layer

The detection and measurement of low concentrations of arsenic (V) are the subjects of intense research interest in chemistry and environmental activity. In this research, a polypyrrole-chitosan/cobalt ferrite nanoparticles composite layer was prepared using an electrodeposition method on a gold-coated glass slide. The composite layer was characterized using field emission scanning electron microscopy, energy-dispersed spectroscopy, atomic force microscopy, and a high surface stylus profilometer. The composite layer was used to detect the arsenic in water, and the sensor limitation was about 0.001 ppm. The composite layer was tested using atomic-force microscopy before and after the detection of arsenic. As a result, the roughness was disoriented, as the arsenic was bound on the surface of the composite layer

Nanoplasmonic sensor based on surface plasmon coupled emission: review

The surface plasmon resonance (SPR) technique is a powerful method to detect chemical molecules. Fluorescent spectroscopy is a subject of great interest in the field of material science and biology. Recently, some optical sensors, based on plasmonic properties of nanomaterial, were introduced to enhance the investigation of the interaction of molecular while detecting the low concentration of molecular. The surface plasmon-coupled emission (SPCE) technique is a merit and accurate method to evaluate the interaction of nanomaterials and molecular. SPCE is based on fluorescence properties of interest molecule, and the surface plasmon enhances the fluorescence signal. According to SPR theory, the condition of excitation of fluorophore could be used in obtaining the SPCE signal. SPCE can be used to detect toxic chemicals and investigate the human molecular. In this review, the theory, experimental setup, condition of SPCE, and role of metal nanoparticles in SPCE were reviewed. In the end, the application of SPCE was presented for detection and monitoring the chemical material, heavy metal, and biologic molecules

Laser Ablation Technique for Synthesis of Metal Nanoparticle in Liquid

Recently, the synthesis and application of metal and ceramic nanoparticle are significant subject in science and engineering. The metal nanoparticles such as silver, gold, and copper nanoparticles have more application in material science, nanomedicine, electronic, photonic, and art. One of the green methods for preparation of metal nanoparticles is laser ablation technique that offers a unique tool for nanofabrication of nanoparticles. In this technique, the high-power laser ablates the metal plate and the nanoparticles are formed in the liquid. The properties of nanoparticles using laser ablation are unique, and they are not reproducible by any other method such as chemical methods. The important parameters to produce the metal nanoparticles are energy, wavelength, repetition rate of laser, ablation time, and absorption of an aqueous solution. Laser ablation is a simple method for fabricating the metal nanoparticles without surfactant or chemical addition. In this chapter, the mechanism of formation of metal nanoparticles in liquid, significant parameters for using the laser ablation technique to prepare the metal nanoparticles, and the preparation of silver, gold and copper nanoparticles will be reviewed

Electromagnetic properties of polytetrafluoroethylene at microwave frequencies using finite element modeling waveguide adapter

Experimental and theoretical approaches were shown great potential to determine electromagnetic properties of dielectric materials at microwave frequencies. In this study, the application of Finite Element Modeling (FEM) of waveguide adapter was utilized to investigate the distribution of electric and magnetic fields intensity of Polytetrafluoroethylene (PTFE) as dielectric sample. Essentially, the electric and magnetic fields intensity in various regions of waveguide were obtained. The computations of the reflection and transmission coefficients of dielectric sample were determined by implementation of Finite Element Methods and Nicolson-Rose-Wire (NRW) method as well. The results were compared with the experimental achievement results using the waveguide adapter in conjunction with a Vector Network Analyzer (VNA) at Microwave frequencies. The general observation indicate that, the level of transmission was greater than reflection for PTFE as dielectric material sample. Furthermore, among the two applied methods, the FEM is more accurate than the NRW method

Investigation on nonlinear-optical properties of palm oil/silver nanoparticles.

The study carried out using continuous wave diode pumped solid state laser with wavelength of 405 nm and power of 50 mW. The strong spatial selfphase modulation patterns were observed that suggest the palm oil/Ag-NPs have a relatively large nonlinear refractive index. The obtained values of nonlinear refractive index were increased with the increase of volume fractions. The observed experimental patterns were also theoretically modeled which are in good agreement with experimental results

Surface plasmon resonance determination of methanol concentration during alkaline transestrification

A surface plasmon resonance (SPR) method was applied to determine the methanol concentration during an alkaline transestrification of the mixture of palm oil and methanol. Theoretically, an SPR signal resonance angle relates with the refractive index of the mixture. Experimental data showed a resonance angle by way of refractive index depends on each volume percentage of palm oil, methanol, and methyl ester. The optimized percentages of volume concentration are found to be 12% methanol and 88% palm oil. At the present measurement precision, it resulted in 2% excess unutilized palm oil or methanol in the biodiesel mixture