• Analytical Science and Technology
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• v.5 no.1
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• pp.7-15
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• 1992

Germainium(IV) was determined in perchloate supporting electrolyte solution containing phenylfluorone by hanging mercury drop electrode(HMDE) of Linear Sweep Voltammetry(LSV) and in hydrochloric acid solution by UV-VIS Spectrophotometry. The complex germanium(IV) with phenylfluorone was shown linear calibration curve in the range of $2.5{\sim}80{\mu}g/L$ by LSV and in the range of $10{\sim}300{\mu}g/L$ by UV-VIS Spectrophotometry.

• YAKHAK HOEJI
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• v.22 no.1
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• pp.27-32
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• 1978

Metoclopramide reacts with ammonium cobaltothiocyanate to form a stable ion pair which has an absorption maximum of 625mm. The reaction product was insoluble in water but soluble in most organic solvents. 1,2-Dichlorethane was the best extracting solvent among the several organic solvents tested. Metoclopramide can be determinded not only by visible light spectrophotometry but also indirectly by estimation of cobalt in the organic phase by flameless atomic absorption spectrophotometry. Linear relationship was found between absorbance and concentration in the range of 10$^{-4/}$-10$^{-3}$M by spectrophotometry and 10$^{-5}$-10$^{-4}$M by flameless atomic absorption spectrophotometry. The coefficient of variation by spectrophotometry was 0.9% and that of flameless atomic absorption was 1.8%. There was no interference with excipients, pH, temperature and reaction time. With this method, it is possible to determine accurately metoclopramide and tertiary amines in pharmaceutical preparations.

• YAKHAK HOEJI
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• v.27 no.4
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• pp.303-307
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• 1983

Pipethanate*HCl reacts with ammonium cobaltothiocyanate to form a stable ion pair which has an absorption maximum at 626nm. The reaction product was insoluble in water but freely soluble in most organic solvents. 1, 2-Dichloroethane was the best extracting solvent among the several organic solvents. Pipethanate*HCl can be determined not only by the spectrophotometry but also inderectly by estimation of cobalt in the organic phase by atomic absorption spectrophotometry. Linear relationship was found between absorbance and concentration in the range of $1.0{\times}10^{-3}~4.0{\times}10^{-3}M$ by spectrophotometry and $1.5{\times}10^{-4}~4.0{\times}10^{-4}M$ by atomic absorption spectrophotometry. With this method it was possible to determine pipethanate$\cdot$HCl in the pharmaceutical preparations.

• Archives of Pharmacal Research
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• v.12 no.3
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• pp.160-165
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• 1989

Binding of sulfaethidole to bovine serum albumin was studied by equilibrium dialysis, fluorescence probe technique, uv difference spectrophotometry and circular dichroism. Equilibrium dialysis method enabled us to estimate the total number of drug binding sites of albumin molecule. For sulfaethidole, albumin had 6 primary and 40 secondary binding sites. The primary and secondary binding constants were 0.9 * 10/sup 5/ M/sup -1/ and 0.2 * 10/sup 6/ M/sup -1/, respectivitely. 1-Anilino-8-naphthalenesulfonate (ANS) and 2-(4-hydroxylbenzeneazo)- benzoic acid (HBAB) were used as the fluorescence probe and the uv spectrophotometric probe, respectively. In fluorescence probe technique, results indicated that the number of higher affinity drug binding site of albumin was 1 and the number of lower affinity drug binding sites of albumin was 3, and the primary and secondary drug binding constants for bovine serum albumin were 2.15 * 10/sup 5/M/sup -1/ and 1.04 * 10/sup 5/ M/sup -1/, respectively. In uv difference spectrophotometry, binding sites were 3 and binding constant was 1.88 * 10/sup 5/M/sup -1/. The above spectrophotometry, binding sites were 3 and binding constant was 1.88 * 10/sup 5/M/sup -1/. The above results suggest that several different methods should be used in ompensation for insufficient information about drug binding to albumin molecule given by only one method.

• YAKHAK HOEJI
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• v.30 no.4
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• pp.185-192
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• 1986

Authors developed the computer application program (language: APPLE SOFT BASIC) for derivative spectrophotometry. By means of this program, derivative of spectral absorbance with respect to wavelength is recorded versus wavelength. To try this program in connection with spectrophotometer system, the authors have done the simultaneous quantitation of pyridoxine center dot HCl and nicotinamide in the mixture, and the result was compared with that of absorbance method.

• Publications of The Korean Astronomical Society
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• v.15 no.spc1
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• pp.39-60
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• 2000

We will discuss two-dimmensional spectrophotometry including long-slit spectroscopy and narrow-band imaging. The basic principles, applications, and techniques of observations and data reduction of spectroscopy and spectrophotometry for extended objects are described. This discussion will focus on practical long-slit spectroscopy using a Cassegrain spectrograph attached with 2 or 4m class telescopes and on imaging spectrophotometry using narrow-band interference filter sets. We will discuss scientific applications.

• Journal of Microbiology and Biotechnology
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• v.6 no.2
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• pp.92-97
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• 1996

Portage kinetic constants of peptide transport can be measured by competitive spectrophotometry. The kinetic constants of L-Glu-L-Glu transport in Escherichia coli were ascertained using L-Phe-L-3-thia-Phe (PSP) as a detector. Since the production of thiophenol upon intracellular hydrolysis of PSP was competitively inhibited by L-Glu-L-Glu, it was able to compute the kinetic constants of L-Glu-L-Glu using this method. The resulted data were in agreement with the values obtained by the method of Michaelis-Menten kinetics. The potential of this method was examined against dipeptide transport systems in various microorganisms. These results strongly suggest that the overall properties of individual systems for dipeptide transports can be easily characterized by competitive spectrophotometry.

• Archives of Pharmacal Research
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• v.10 no.1
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• pp.1-8
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• 1987

One of the problems of derivatie spectrophotometry, the decrease of signal-to-noise ratio by derivative operations, was solved by three concepts of digital filtering, ensemble averaging, least squares polynomial smoothing and Fourier smoothing. The suthors made several compouter programs written in APPLE SOFT BASIC language for the actual applications of the concepts of these digital filters on UV spectrophotometer system. As a result, ensemble averaging could not be used as a routine operation for the spectrophotometer used. The maximum S/N ratio enhancement factors achieved by least squares polynomial smoothing were 6.17 and 7.47 for the spectra of Gaussian and Lorentzian distribution models, and by Fourier smoothing 16.42 and 11.78 for the spectra of two models, respectively.

• Bulletin of the Korean Chemical Society
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• v.19 no.6
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• pp.689-695
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• 1998

Carbobenzoxy-alanyl-thiaarginine benzyl ester and carbobenzoxy-alanyl-thialysine benzyl ester were synthesized in solution. Kinetic studies were carried out using three different analytical methods, semi-classical method, progress curve analysis and competitive spectrophotometry. In competitive spectrophotometry, carbobenzoxy-valyl-glycyl-arginyl-p-nitroaniline was used as a detector. Kinetic constants such as $K_m$ and $V_{max}$ measured by competitive spectrophotometry are almost the same as those values measured by semi-classical method. Colorimetric Ellman's assays showed the thio-peptido mimetics to be a suitable substrates for trypsin. Kinetic studies with trypsin gave $K_m$ of 2.33 mM and $k_{cat}$ of $1.50{\times}10^5\;min^{-1}$ for carboxy-alanyl-thiaarginine benzyl ester and $K_m$ of $3.41{\times}10^{-3}\; Mm\; and\; k_{cat}\; of\; 520{\times}102\; min^{-1}$ for carbobenzoxy-alanyl-thialysine benzyl ester, respectively. Kinetic constants $(K_m=2.04{\times}10^{-2}\; mM, K_{cat}=4.42{\times}10^3 \;min^{-1})$ for natural substrate, carbobenzoxy-alanyl-lysine benzyl ester, were also evaluated by competitive spectrophotometry in order to compare the mode of binding on trypsin.

• Applied Biological Chemistry
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• v.48 no.2
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• pp.183-188
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• 2005

This study was conducted to develop a method for the quantitative determination of soil clay content by spectophotometry. The optimum wavelength obtained with reference clay minerals for spectrophotometry was 500 nm. For the proposed spectrophotometry, 0.5 g of soil sample was put in the 250 ml Erlenmeyer flask and 100 ml dispersing agent was added. After shaking the flask at 130 rpm with a mechanical shaker overnight, the flask was removed from the shaker and was shaken up-and-down for 30 seconds. With a micro-pipet, 4 ml of the suspension was transferred into the previously-inserted cell and the absorbance was measured instantly. Results by the spectrophotometry for clay content analysis were compared with those by the conventional sedimentation technique (the pipet method). The proposed equation was $y\;=\;38.03x_1-0.17x_2-1.17$, where y, $x_1$, and $x_2$ were clay content (%) by the pipet method, water content corrected clay content (%) by spectrophotometry, and organic matter content ($g{\cdot}kg^{-1}$), respectively. The regression coefficient for the equation was $r\;=\;0.984^{**}$, indicating highly significant correlation between the results of the two methods.