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This paper presents the development and experimental analysis of a curved microelectrode platform for the DEP deformation of breast cancer cells (MDA-MB-231). The platform is composed of arrays of curved DEP microelectrodes which are patterned onto a glass slide and samples containing MDA-MB-231 cells are pipetted onto the platform's surface. Finite element method is utilised to characterise the electric field gradient and DEP field. The performance of the system is assessed with MDA-MB-231 cells in a low conductivity 1% DMEM suspending medium. We applied sinusoidal wave AC potential at peak to peak voltages of 2, 5, and 10 Vpp at both 10 kHz and 50 MHz. We observed cell blebbing and cell shrinkage and analyzed the percentage of shrinkage of the cells. The experiments demonstrated higher percentage of cell shrinkage when cells are exposed to higher frequency and peak to peak voltage electric field.

The recent advancement of dielectrophoresis (DEP)-enabled microfluidic platforms is opening new opportunities for potential use in cancer disease diagnostics. DEP is advantageous because of its specificity, low cost, small sample volume requirement, and tuneable property for microfluidic platforms. These intrinsic advantages have made it especially suitable for developing microfluidic cancer diagnostic platforms. This review focuses on a comprehensive analysis of the recent developments of DEP enabled microfluidic platforms sorted according to the target cancer cell. Each study is critically analyzed, and the features of each platform, the performance, added functionality for clinical use, and the types of samples, used are discussed. We address the novelty of the techniques, strategies, and design configuration used in improving on existing technologies or previous studies. A summary of comparing the developmental extent of each study is made, and we conclude with a treatment of future trends and a brief summary.

Spinal Muscular Atrophy (SMA) is the second most frequent fatal autosomal recessive disorder of childhood. The incidence of this disease is approximately 1 in 10000 live births. SMA is characterized by progressive muscle weakness resulting from degeneration and loss of motor neurons in the anterior horn of spinal cord. The responsible genes for SMA are Survival of Motor Neuron (SMN). SMN1 and SMN2 genes share over 99.8% sequence homology and they can be distinguished by base changes in both exons 7 and 8. SMN1 gene is not detectable in majority of SMA cases due to either deletion or conversion. Conventionally, the homozygous deletion of SMN1 gene is detected using Polymerase Chain Reaction-Restriction Enzyme (PCR-RE) method. This method is time consuming, expensive and requires restriction enzyme digestion and a considerably high amount of amplified DNA to be visible after digestion. This may lead to false-negative results. To avoid these problems, we have developed an alternative method using an allele-specific primer for the molecular diagnosis of SMA which is more time-saving and cost-effective. The freeze dry platform was applied to the multiplex AS-PCR for the development of a thermostabilize diagnostic kit. A total of one hundred and forty three samples of clinically suspected SMA were included in this study. Conventional molecular diagnosis using PCR-RE was done to detect the presence or absent of SMN1 deletion in these samples.