Stabilization of human urine doping control samples: IV. Human chorionic gonadotropin

STORAGE OF ACTIVITY OF THE HUMAN CHORIONIC GONADOTROPIN HORMONE IN SOLUTION AT ADDITION OF ORGANIC COMPOUNDS TO THE PHARMACOLOGICAL COMPOSITION

The more stable among the tested samples were samples with saccharose in the concentration of 50–75 mg per cm3. While adding of L- lysine to samples the most stable activity was discovered in the experimental series of samples with the content of lysine of 10 mg per cm3 – activity increased by 54 % as compared to theoretical initial activity of HCG during 8 weeks. While storing gonadotropin with L-glycine fluctuations of hormone activity in all series of samples were observed. Adding of 0.2 mg per cm3 of L-glycine had a more expressed stabilizing effect. Adding of 0.2 mg per cm3 of L-methionine produced relatively high and stable activity of gonadotropin during the 6 weeks storage. Adding of 0.25 mg / cm3 of L- glycine and 75.50 mg / cm3 of saccharose to experimental samples during 2 weeks at 40 °C provided 69.8 % and 60.7 % saving activity of hCG respectively. Activity of gonadotropin in a series of samples with the addition of L- glycine and mannitol was significantly lower and at the end of the study was at an appropriate rate with the control series models. The highest activity of gonadotropin was detected while adding fillers – 10 mg / cm3 L-lysine and 75 mg / cm3 saccharose and mannitol – to recipes as a stabilizer.

Fluorescence flow cytometer to determine urine particle reference intervals in doping control samples

BACKGROUND

Urine is still the matrix of choice to fight against doping, because it can be collected non-invasively during anti-doping tests. Most of the World Anti-Doping Agency's accredited laboratories have more than 20 years experience in analyzing this biological fluid and the majority of the compounds listed in the 2010 Prohibited List-International Standard are eliminated through the urinary apparatus. Storing and transporting urine samples for doping analyses does not include a specific protocol to prevent microbial and thermal degradation. The use of a rapid and reliable screening method could enable determine reference intervals for urine specimens in doping control samples and evaluate notably the prevalence of microbial contamination known to be responsible for the degradation of chemical substances in urine.

METHODS

The Sysmex® UF-500i is a recent urine flow cytometer analyzer capable of quantifying BACT and other urinary particles such as RBC, WBC, EC, DEBRIS, CAST, PATH.CAST, YLC, SRC as well as measuring urine conductivity. To determine urine anti-doping reference intervals, 501 samples received in our laboratory over a period of two months were submitted to an immediate examination. All samples were collected and then transported at room temperature. Analysis of variance was performed to test the effects of factors such as gender, test type [in-competition, out-of-competition] and delivery time.

RESULTS

The data obtained showed that most of the urine samples were highly contaminated with bacteria. The other urine particles were also very different according to the factors.

CONCLUSIONS

The Sysmex® UF-500i was capable of providing a snapshot of urine particles present in the samples at the time of the delivery to the laboratory. These particles, BACT in particular, gave a good idea of the possible microbial degradation which had and/or could have occurred in the sample. This information could be used as the first quality control set up in WADA (World Anti-Doping Agency) accredited laboratories to determine if steroid profiles, endogenous and prohibited substances have possibly been altered.