ABSTRACT
For identifying and quantifying prohibited substances,solid-phase microextraction(SPME)continues to arouse interest as a sample preparation method.However,the practical implementation of this method in routine laboratory testing is currently hindered by the limited number of coatings compatible with the ubiquitous high-performance liquid chromatography(HPLC)systems.Only octadecyl(C18)and poly-dimethylsiloxane/divinylbenzene ligands are currently marketed for this purpose.To address this situ-ation,the present study evaluated 12 HPLC-compatible coatings,including several chemistries not currently used in this application.The stationary phases of SPME devices in the geometry of thin film-coated blades were prepared by applying silica particles bonded with various functional ligands(C18,octyl,phenyl-hexyl,3-cyanopropyl,benzenesulfonic acid,and selected combinations of these),as well as unbonded silica,to a metal support.Most of these chemistries have not been previously used as microextraction coatings.The 48 most commonly misused substances were selected to assess the extraction efficacy of each coating,and eight desorption solvent compositions were used to optimize the desorption conditions.All samples were analyzed using an HPLC system coupled with triple quadrupole tandem mass spectrometry.This evaluation enables selection of the best-performing coatings for quantifying prohibited substances and investigates the relationship between extraction efficacy and the physicochemical characteristics of the analytes.Ultimately,using the most suitable coatings is essential for trace-level analysis of chemically diverse prohibited substances.
ABSTRACT
Objective To introduce a practical high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS)method for the detection of seven growth hormone-releasing peptides (GHRPs)including GHRP-1,GHRP-2,GHRP-4,GHRP-5,GHRP-6,Hexarelin and Alexamorelin and two growth hormone secretagogues(GHS)including anamorelin and ipamorelin,and study the stability of these nine substances in the human urine.Method The urine samples were purified and extracted by a solid phase extraction procedure using Oasis(R) WCX column.The urine was first centrifuged and taken out 1 mL into a small column,cleaned by 5％ NH4OH and 20％ CH3CN respectively,eluated using the mixture of water and acetomitrile(1/3)with 2％ formic acid,blow-dried in the nitrogen at 35℃ and finally redissolved to be injected into the LC-MS/MS.Result The limits of detection were between 0.01～0.5 ng/mL accordingly.The spiked recoveries at the low concentration(1 ng/mL),medium concentration(2 ng/mL)and high concentration(10 ng/mL)ranged between 40％ and 76％.The intra-and interday precisions of the target substances at these three concentrations were all less than 15％.The indoor temperature,refrigeration condition and multigelation were observed to have significant impact on the anamorelin,GHRP-2,GHRP-4 and GHRP-5.Conclusion The method established in this study is simple,and its specificity and sensitivity meets the international standard and technical documents for laboratories set up by the Wworld Anti-Doping Agency.It has been applied in our routine work.Multigelation should be avoided in the transport,detection and long-term laboratory storage of urine samples.
ABSTRACT
<b>Objective: </b>Doping is strongly prohibited in sports. Sports pharmacist was born in 2010 in Japan, and the anti-doping activity is expected. On the other hand, doping by arising from a lack of knowledge about prohibited substances in athletes, so-called “unwilling doping” is developing into a social issue. In this study, we investigated the percentage of prohibited substances in all drugs and prescriptions in a general hospital, to collect information to prevent an unwilling doping.<br><b>Methods: </b>We constructed system to extract the drugs corresponding to prohibited substances in the prescription order entry system in Otaru Municipal Hospital, and we analyzed 3,306 prescriptions of 10 to 59 years old patients, from July to September 2010.<br><b>Results: </b>Thirteen point five percent of our hospital drugs met definition of the prohibited substance. The number of prescriptions including prohibited substance(s) was 350 (10.6%), and its category was different from each age-group and clinical department.<br><b>Consideration: </b>Because prohibited substances are included in approximately 10% of prescriptions, athletes are exposed to danger of becoming an unwilling doping. Pharmacist should be well informed about prohibited substances to prevent athletes from unwilling doping. And they should provide information promptly and adequately for athletes.