• Mass Spectrometry Letters
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• 제10권4호
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• pp.108-111
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• 2019

The hydrolysis of penicillin G, carbenicillin and ampicillin in pure water at room temperature was studied by high pressure liquid chromatography electrospray ionization mass spectrometry. Hydrolysis of ampicillin did not occur under these conditions; however, penicillin G and carbenicillin were completely hydrolyzed after seven days. A short interpretation of this difference is proposed. The mass spectrometric behaviour, namely ESI response and fragmentation pathway, of hydrolyzed penicillin G and hydrolyzed carbenicillin have been also discussed.

• Bulletin of the Korean Chemical Society
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• 제35권10호
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• pp.3103-3106
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• 2014

• Bulletin of the Korean Chemical Society
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• 제29권11호
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• pp.2125-2128
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• 2008

• 약학회지
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• 제23권1호
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• pp.7-10
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• 1979

A gas chromatographic determination of dienestrol in dienestrol cream has been studied. Dienestrol cream was dissolved in pyridine and silylation was done by using N, O-bis (trimethylsilyl) trifluoroacetamide. The derivative was injected into 3% silicone OV-17 column for chromatographic estimation. The dienestrol peak was found to be well separated from the other components of the cream. The detection limit was obtained to be $5.6{\times}10^{11}$ mol of dienestrol for this method. As there is no need for prior separation procedure, this experiment is extremely simple and less time consuming as compared to the conventional methods for estimation of dienestrol in cream.

• Bulletin of the Korean Chemical Society
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• 제24권10호
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• pp.1517-1520
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• 2003

• Bulletin of the Korean Chemical Society
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• 제34권5호
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• pp.1571-1574
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• 2013

• 한국방사성폐기물학회:학술대회논문집
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• 한국방사성폐기물학회 2005년도 Proceedings of The 6th korea-china joint workshop on nuclear waste management
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• pp.107-116
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• 2005

Precipitated silicas modified by aluminium were characterised using inverse liquid chromatography in anhydrous heptane with squalene as probes. Their monolayer capacities of adsorption, Langmuir's and Henry's constants were determined from the desorption isotherms according to frontal analysis. A narrow band consisting of isotherms was observed. The introduction of aluminium has little influence on the monolayer capacity, Langmuir's constants and the Henry constant. Experimental data show that neither the amounts of aluminium on the silica nor the methods of the introduction of aluminium into the silica influence the interactions between the squalene and the silicas.

• 생약학회지
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• 제24권4호
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• pp.309-312
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• 1993

A new method for separation and quantitative determination of isoflavone glucosides in rhizomes of Belamcanda chinensis (Iridaceae) by high performance liquid chromatography was elaborated. A reverse-phase system with a Spheri-5 RP-18 column using MeOH:HOAc:$H_2O$(24 : 5 : 71) as a mobile phase was developed. The isoflavonoids were detected at 268 nm and the analysis was successfully carried out within 15 min.

• Bulletin of the Korean Chemical Society
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• 제15권10호
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• pp.868-873
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• 1994

We have re-examined the linear solvation energy relationships in reversed phase liquid chromatography by considering various solutes including quite a number of compounds of strong hydrogen bond capability. We observed that solutes of strong hydrogen bond ability should be excluded in order to obtain resonable correlations between In k' and solute polarity parameters and that inclusion of one or two such solutes causes severe distortions of correlation results. This anomaly may be due to existence of residual silanol groups in the stationary phase, that is, their specific interactions with solutes.

• 대한약학회:학술대회논문집
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• 대한약학회 2002년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2
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• pp.423.1-423.1
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• 2002

A simple. specific and sensitive method for the determination of cyclosporine A (CsA) in human serum has been developed by a high performance liquid chromatography/diode array detector (DAD) and applied to pharmacokinetic study of CsA. This method involves the use of solid phase extraction procedure following rapid protein precipitation with zinc sulphate from 1 $m\ell$ of human serum, using a disposable $C_{18}$ extraction cartridge. (omitted)