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In this work, a smartphone based optical platform for colorimetric analysis of blood hematocrit using a disposable microfluidic device is designed, implemented and fully characterized. Using an integrated camera in the smartphone, pictures of human blood in the microchannel were taken and analyzed by a mobile application. To avoid the image burning and ambient light effect, a unique light-diffusing model inside a white acrylic-imaging box was included in this platform. With the image-processing program on the smartphone, the developed device was successfully applied to determine various hematocrit levels of human blood from 10% to 65%. Furthermore, the characterization of the depth of the microfluidic channel demonstrated that a shallower depth of the microchannel enhanced the sensitivity of the hematocrit determination. The limit of detection (LOD) obtained from the developed platform was 0.1% of hematocrit with a sensitivity of 0.53 GSV (a.u.)/hematocrit%. Thus, utilizing the advantage of the microfluidic effect, a rapid and sensitive hematocrit determination was achieved successfully. With this, the hematocrit of human blood could be conveniently and accurately determined using the disposable microfluidic device, and then processed by the smartphone camera and mobile image analysis application.

A novel and rapid analysis technique using histogram has been proposed for the colorimetric quantification of blood hematocrits. A smartphone-based "Histogram" app for the detection of hematocrits has been developed integrating the smartphone embedded camera with a microfluidic chip via a custom-made optical platform. The developed histogram analysis shows its effectiveness in the automatic detection of sample channel including auto-calibration and can analyze the single-channel as well as multi-channel images. Furthermore, the analyzing method is advantageous to the quantification of blood-hematocrit both in the equal and varying optical conditions. The rapid determination of blood hematocrits carries enormous information regarding physiological disorders, and the use of such reproducible, cost-effective, and standard techniques may effectively help with the diagnosis and prevention of a number of human diseases. (C) 2017 Optical Society of America.

A novel device of smart pipette has been suggested to extract and deliver plasma from whole blood in a disposable format. By operating an on-chip disposable micropump, approximately 30 μL of plasma was obtained from 100 μL of whole blood within 5 min without any external equipment for point-of-care blood analysis.

Methane is the main component of natural gas and has been connected with global warming. The oxidative coupling of methane has been studied to enhance C2 hydrocarbon selectivity and to reduce the formation of carbon oxides associated with C2 hydrocarbon production. Acid sites of supported catalysts play a role in the formation of carbon oxides. The supported Zn oxide catalyst with α-Al2O3 shows no acidity in temperature programmed desorption by using NH3 and exhibits good C2 hydrocarbon selectivity. The optimum loading of Zn oxide on α-Al2O3 is 60 wt%. The specific surface area of the catalyst appears not to influence activity. Using alkali metal salts as promoter in Zn oxide (60 wt%)/α-Al2O3 catalyst, the activity performance for C2 hydrocarbon formation is LiCl > NaCl > KCl: the performance is well correlated with the apparent molal enthalpy of formation of halides. The activity performance for minimizing carbon oxides is LiCl > KCl > NaCl, which is well correlated with the melting points in alkali halides.

Dehydroepiandrosterone sulfotransferase (Std) catalyzes sulfonation of androgenic steroids and certain aromatic procarcinogens. In rats, this enzyme is selectively expressed in the liver, and its expression is strongly repressed by androgens. DNase I footprinting and electrophoretic mobility shift analyses revealed two hepatocyte nuclear factor-1 (HNF1), three CCAAT/enhancer-binding protein (C/EBP), and one consensus palindromic thyroid hormone response elements within the first 215 base pairs (bp) of the promoter sequence of rat Std. This promoter is normally inactive in fibroblast-derived NIH 3T3 cells. However, overexpression of HNF1 and C/EBP resulted in synergistic activation of the Std promoter in this cell type, indicating essential roles of these two trans-regulators in liver-selective expression of the rat Std gene. On the other hand, point mutations at any one of five cis elements proximal to the -215 bp region markedly reduced reporter gene expression, suggesting that all of these sites are important for overall promoter function. Androgenic repression of the Std gene in rat liver can be recapitulated in androgen receptor (AR)-negative HepG2 hepatoma cells after cotransfection with an AR expression plasmid. Functional assay of a nested set of 5'-deleted promoters mapped the negative androgen response region between positions -235 and -310. Antibody supershift and oligonucleotide competition identified three OCT-1 and two C/EBP elements between bp -231 and -292. An additional OCT-1 site was found to overlap with a C/EBP element at the -262/-252 position. Mutational inactivation of any one of five cis elements within the -231/-292 region abolished negative androgen response. However, none of these cis elements showed DNase I protection by recombinant AR in footprinting assay, suggesting the absence of a direct AR-DNA interaction. Thus, these studies on rat Std promoter function indicate that (i) HNF1 and C/EBP are responsible for liver specificity of the rat Std gene; (ii) androgenic repression of the gene requires the presence of all of the OCT-1 and C/EBP elements between positions -231 and -292; and (iii) AR may exert its negative regulatory effect indirectly through transcriptional interference of OCT-1 and C/EBP rather than through a direct DNA-AR interaction.