• YAKHAK HOEJI
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• v.57 no.5
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• pp.330-336
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• 2013

"The Act on Medication Treatment of Sexual Impulse of Sex Offenders" known as chemical castration has been effective since July 2011 in Korea. According to the law, monitoring of male sex hormone in urine is enforced to request National Forensic Service more than once a month after injection of medicine designed to reduce sex impulse. We established a rapid and sensitive method for the monitoring of testosterone (T) and epitestosterone (E) in human urine by liquid chromatography with tandem mass spectrometry (LC-MS/MS). Three mL of urine was pretreated by solid-phase extraction for purification and performed enzymatic hydrolysis. The pretreated samples were extracted twice with 2 ml of ethyl acetate and n-hexane (2 : 3). The separation was applied on Thermo Hypersil GOLD C18 column ($1.9{\mu}m$, $100{\times}2.1mm$). A gradient elution of methanol and water of 0.1% formic acid were used as mobile phase and the retention time was less than 10 min. LC-MS/MS system coupled with an electrospray ionization source was performed in multiple reaction monitoring mode. The transitions of the analytes executed as following: m/z $289{\rightarrow}97$, 109 for T and E, m/z $292{\rightarrow}109$ for $T-d_3$ and $E-d_3$ as internal standards. The validation results of the method were satisfactory. The limits of detection were 0.05 ng/ml and the limits of quantification were 0.1 ng/ml. This method was successfully applied to real human urine sample. The developed method will be useful for monitoring T/E ratio in urine of sex offenders.

• Proceedings of the PSK Conference
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• 2002.10a
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• pp.406.2-406.2
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• 2002

Special attention has been paid to human chorionic gonadotropin (hCG) for athlete doping control because it stimulates the endogenous production of testosterone and epitestosterone without increasing the T/E ratio which is a doping indicator for the exogenous administration of testosterone. Even though the IOC banned the use of hCG. a detection method has not been decided upon since there are a variety of immunoassay kits available on the market. We evaluated three kits in terms af their performance characteristics. (omitted)

• Mass Spectrometry Letters
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• v.1 no.1
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• pp.29-32
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• 2010

Cross reacting antibodies can cause an overestimation of the results of immunoassays. Therefore, alternative methods are needed for the accurate quantification of steroids. Gas chromatography combined with isotope-dilution mass spectrometry (GC-IDMS) is developed to quantify urinary active androgens, testosterone, epitestosterone and dihydrotestosterone, which are clinically relevant androgens to both hair-loss and prostate diseases. The method devised involves enzymatic hydrolysis with $\beta$-glucuronidase, solid-phase extraction, liquid-liquid extraction using methyl tert-butyl ether and subsequent conversion to pentafluorophenyldimethylsilyl-trimethylsilyl (flophemesyl-TMS) derivatives for sensitive and selective analysis in selected-ion monitoring mode. Flophemesyl-TMS derivatization not only eliminates matrix interference but also has a good peak resolution within a 6 min-run. A selective and sensitive GC technique with flophemesyl-TMS derivatives also allows accurate quantitative analysis of three active androgens when combined with IDMS. The limit of quantification of the three analytes was <50 pg/mL, and extraction recoveries ranged from 91.9 to 102.1%. The precision and accuracy were 1.2~6.5% and 89.0~106.7%, respectively. This GC-IDMS method can be useful for evaluating the drug efficacy and monitoring the biological processes responsible for male-pattern baldness and prostate diseases.

• Biomolecules & Therapeutics
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• v.10 no.3
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• pp.186-192
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• 2002

Special attention has been paid to human chorionic gonadotropin (hCG) for athlete doping control because it stimulates the endogenous production of testosterone and epitestosterone without increasing the T/E ratio which is a doping indicator for the exogenous administration of testosterone. Even though the IOC banned the use of hCG, a detection method has not been decided upon since there are a variety of immunoassay kits available on the market. We evaluated three kits in terms of their performance characteristics. The assay value of the control sample varied depending on the kit, resulting in 198 mIU/ml for the MAIA kit, 172mIU/ml for the IRMA kit, and 143 mIU/ml for the MEIA kit. Considering the IOC inter-lab distribution of results(55-312 mIU/ml) using 27 different kits and the mean value (178$\pm$56 mIU/ml), all three kits are within the range of －15.8% - ＋5.6% of the mean value, which proves them useful for the hCG assay. The MEIA kit resulted in lower hCG values because it detects only intact hCG molecules, in contrast to the other two kits which detect intact hCG and -hCG together. However, it is suitable for screening purposes because of its advantage of being an automated system. When 123 urine samples of athletes were analyzed in 22 batches using this system, the variation of control values fell within $\pm$ 10% of the mean values, and an specimens tested negative with hCG values less than the detection limit of 2 mIU/ml.