Papers by Author: Mohamad Rusop

Abstract: Tin-doped Zinc Oxide (Sn-doped ZnO) thin films were prepared using zinc acetate dehydrate as a starting material by sol-gel immersion method. The doping concentrations were varied at 0 at.%, 0.5 at.%, 1.0 at.%, 2.0 at.%, 3.0 at.% and 4.0 at.%. The synthesized samples were characterized by current-voltage (I-V) measurement and UV-VISS spectrometer.

Abstract: The most important thing in preparing thin films ceramic material such lead titanate, PbTiO₃ is the behavioral of microstructural changes due to the applying heat treatment during crystallization process. In general, the imperfection of PbTiO₃ surface morphology such as porosity, grain boundaries, existence of microcrack films, films out-diffusion and others are caused by this factor, heat transfer element and found very interesting to be discussed towards next electrical characterization. However, the present study only focuses on the surface morphology of PbTiO₃ thin films that observed by both field emissions scanning electron microscopy (FESEM) and atomic force microscopy (AFM). The details of measurement for observation will be explained later. The preparation of PbTiO₃ thin films were done trough simple sol-gel spin coating method deposited on ITO coated glass substrate.

Abstract: In this paper, carbon nanotubes on porous silicon substrate were developed in order to get high quality nanotubes for various kind of application. CNTs were deposited on porous silicon nanostructures (PSiN) at 750 0C on porous silicon by using double-furnace thermal chemical vapor deposition technique. Align carbon nanotubes with diameters of 15 to 30 nm were successfully synthesized on a porous silicon substrate. In this system, carbon nanotubes were grown directly on the p-type porous silicon surface at 750 0C for a total time of 30 minutes. The samples were characterized using field emission scanning electron microscopy and micro-Raman spectroscopy. Align carbon nanotubes (ACNTs) bundle with uniform diameter (~20 nm) were found grown on porous silicon at certain area. Based on micro-Raman spectroscopy result, the peak of silicon at ~520 nm and peak of carbon nanotube (around 1 300 to 1 600 nm) was detected.

Abstract: Carbon nanotubes (CNTs) were reported to cause severe toxicity in in vivo and in vitro studies. On the other hand, CNTs has the potential as a mechanism for drug delivery across the blood brain barrier due to its nano-sized dimensions. The present preliminary study examined the cytotoxic effect of CNTs in serum-free and serum-containing EMEM medium on neuroblastoma cells growth. The MTS assay showed that CNTs did not cause any cytotoxicity at concentrations below 0.1 mg/mL at 24 and 48 h incubation in serum-containing EMEM medium. This finding suggested that below 0.1 mg/mL, CNTs can be used as a mechanism for drug delivery for the treatment of neuronal cancer. However, CNTs showed slighty toxic towards neuroblastoma cells at concentration 0.1 mg/ml at 48h incubation in serum-free EMEM medium. This finding indicates that the present of serum play a role for toxicity effect of CNTs in cells.