Power electronics and fuel cell technologies play an important role in the field of renewable energy. The demand for fuel cells will increase as fuel cells become the main power source for portable applications. In this application, a high-efficiency converter is an essential requirement and a key parameter of the overall system. This is because the size, cost, efficiency, and reliability of the overall system for portable applications primarily depend on the converter. Therefore, the selection of an appropriate converter topology is an important and fundamental aspect of designing a fuel cell system for portable applications as the converter alone plays a major role in determining the overall performance of the system. This paper presents a review of power electronics applications in fuel cell systems, which include various topology combinations of DC converters and AC inverters and which are primarily used in fuel cell systems for portable or stand-alone applications. This paper also reviews the switching techniques used in power conditioning for fuel cell systems. Finally, this paper addresses the current problem encountered with DC converters and AC inverter.

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Purpose: To investigate the efficiency of different solubilizing agents in improving solubility as well as dissolution rate of ebastine (a BCS class II drug) by incorporating prepared solid dispersion into fast disintegrating tablets.Method: The solubility of ebastine was determined in distilled water, lipids and solubilizing agents. Subsequently, the binary solid dispersions were prepared by kneading method using varying weight ratios of ebastine and solubilizing agents. The solid dispersions were then incorporated into fast disintegrating tablets (SD-FDT). Central composite rotatable design (CCD) was used to determine the impact of super disintegrating agents on disintegration time and friability of tablets. The solubility and dissolution rate of developed SD-FDT were compared with a marketed brand. The solid dispersion particles were characterized by Fourier-transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), powder x-ray diffraction (P-XRD) and scanning electron microscopy (SEM).Results: The saturated solubility of pure ebastine in water was 0.002 ± 0.041 mg/ml while the aqueous solubility of EBT/poloxamer solid dispersion SET3 (P) was 0.018 ± 2.510 mg/ml; on the other hand, EBT/soluplus solid dispersion SET1(S) has an aqueous solubility of 0.242 ± 1.390 mg/ml. Within 30 min, drug release was 14.00 ± 1.77, 78.00 ± 2.31 and 98.70 ± 2.54 % from pure EBT, SET3 (P) and SET1(S), respectively.Conclusion: The solubility and dissolution rate of ebastine has been successfully enhanced by incorporating its solid dispersion in fast-disintegrating tablets (SD-FDT). Keywords: Ebastine, Solid dispersion, Poloxamer 188, Soluplus, Solubility, Dissolution

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