Now showing 1 - 3 of 3
  • Publication
    Numerical Simulation of Transdermal Iontophoretic Drug Delivery System
    Transdermal Iontophoretic Drug Delivery System (TIDDS) is a non-invasive method of systemic drug delivery that involves by applying a drug formulation to the skin. The drug penetrates through the stratum corneum, epidermis and dermis layers. Once the drug reaches the dermal layer, it is available for systemic absorption via dermal microcirculation. However, clinical testing of new drug developed for the iontophoretic system is a long and complex process. Recently, most of those major pharmaceutical companies have attempted to consider computer-based bio-simulation strategies as a means of generating the data necessary to help make a better decision. In this work, we used computational modelling to investigate the TIDDS behaviour. Our interest is to study the efficacy of drug diffusion through transdermal delivery, including the thermal effect on the skin. We found that drug will be delivered more efficiently if the electrical potential and the position of electrodes are optimum. We analysed the drug diffusion time of the system using 1,3 and 5 mA DC source. In addition, we also modify the electrode distance from 10 mm to 30 mm long and analysed the effect of delivery time and d effect to the skin thermal. We conclude that, a high electrical current, as instance, a 5 mA DC, delivered the drug faster into the skin but increased the skin temperature because of skin joule heating effect. However, a 30 mm electrodes distance setting decreased the skin temperature significantly than the 10 mm distance with more than 9.7 °C under 5 mA DC and 60 minutes of operation. TIDDS enhanced drug delivery compared to oral consumption and might be suitable used for localizing treatments such as chronic disease. This work provides great potential and is useful to efficiently design of iontophoretic drug delivery system including new drugs delivery applications.
  • Publication
    Modelling and Simulation using Finite Element Method of Surface Acoustic Wave Biosensor for Gas Detection Application
    A surface acoustic wave (SAW) sensor detects changes in physical properties such as mass and density on its surface. Compared to other types of sensors, SAW sensor have a good stability, high selectivity and sensitivity, fast response, and low-cost. On the other hand, to design and optimize a SAW biosensor requires a long process including time and cost using conventional methods. Therefore, numerical simulation and computational modelling are useful and efficiently conduct analysis for the SAW biosensor. In this paper, a numerical simulation technique is used to analyse the SAW device sensitivity for the application of gas detection. The SAW biosensor can detect very small mass loading by changing its sensor resonance frequency. The two-dimensional (2D) device model is based on a two-port SAW resonator with a gas sensing layer. We made two design of SAW biosensor device with frequency of 872 MHz and 1.74 GHz. A gas with vary concentration from 1 to 100 ppm were used to determine the change of the device resonance frequency. As a result, the high frequency (1.74 GHz) device, shows that the resonance frequency is shifted larger than to the low frequency (872 MHz) device. In addition, the high frequency device offers five times more sensitivity than the low frequency device. By changing the sensor design, the sensor characteristics such as sensitivity can be altered to meet certain sensing requirements. Numerical simulation provides advantages for sensor optimization and useful for nearly representing the real condition.
  • Publication
    Process development and characterization towards microstructural realization using laser micromachining for MEMS
    ( 2020-05-01) ;
    Elden Harrison Felix
    ;
    ;
    Muhamad Nasir Bakar
    This paper presents the process development and characterization towards microstructural realization using laser micromachining for MEMS. Laser micromachining technique is environmental friendly, fast patterning and able to avoid multi steps in conventional lithography based microfabrication techniques. This research focuses on understanding the dimensional properties of materials of the laser beam on the silicon wafers where microstructures were fabricated. Four main parameters like rectangular variable aperture (RVA-XY) size, number of pulse, stage/table feed rate and laser energy play important role in laser ablation process. The pattern of the microchannel or line with 1 cm length was drawn by AutoCAD software or any CAD software. The pattern in the CAD software is then transferred onto the silicon wafer by using laser micromachining. Finally, high power microscope (HPM) and Stylus Profiler will be used as measurement tools for observing and analysing the width and depth of the microchannel structures fabricated by laser micromachining. When using bigger size of RVA, it will lead to bigger microchannel width. There are a little effects or almost comparable in term of microchannel depth if varying all parameters’ value. Surface roughness test also needs to be considered before choosing the best setting for the laser ablation.