Untitled

Abstract

The urinary concentrations of the main metabolites of methamphetamine (MA), speciˆcally p hydroxymethamphetamine-sulfate (p OHMA-Sul) and p hydroxymethamphetamine-glucuronide (p OHMA-Gul) have been directly measured in MA users using an optimized LC ESI MS method.The concentrations of the main metabolites and unchanged MA in 50 MA users' urine ranged from 0.02 to 21.7 mg/ml for p OHMA Sul, from ＜0.02 to 2.43 mg/ml for p OHMA Glu, from ＜0.005 to 1.33 mg/ml for p hydroxymethamphetamine (p OHMA), from 0.01 to 6.79 mg/ml for amphetamine (AP) and from 0.04 to 133 mg/ml for MA, and the ratios of sulfate to glucuronide (S/G ratios) ranged from 2.2 to 37.1 (13.8±8.1). These results demonstrate that the majority of p OHMA is eliminated as its conjugate and the sulfation is quantitatively more important than glucuronidation for the conjugation of p OHMA in humans. The urinary concentration time-dependency in two MA users have also revealed that the conjugates were mostly excreted in urine within 3 days post-intake.Both the acid and enzymatic hydrolysis conditions for p OHMA conjugates were also optimized using the authentic standards of p OHMA Sul and p OHMA Gul. In the acid hydrolysis, the hydrolysis rate of p OHMA Sul was faster than p OHMA Glu, and a 3 h incubation with 1.2 mol/l HCl at 98 degrees Celsius gave complete hydrolysis of p OHMA Sul and p OHMA Glu. On the other hand, the enzymatic hydrolysis of two conjugates with Sulfatase Type H 1 from Helix pomatia required 6 hours for completion.

Development of simultaneous gas chromatography–mass spectrometric and liquid chromatography–electrospray ionization mass spectrometric determination method for the new designer drugs, N-benzylpiperazine (BZP), 1-(3-trifluoromethylphenyl)piperazine (TFMPP) and their main metabolites in urine

“…2, the levels of the three metabolites were all increased with time up to approximately 6 h, and then showed no noticeable change. To confirm the complete hydrolysis of the conjugates, the glucuronides and sulfates of the three metabolites were monitored by measuring the ions corresponding to each conjugate (m/z 369 and 273 for glucuronides and sulfates of OH-BZPs, and m/z 423 and 327 for glucuronide and sulfate of p-OH-TFMPP, respectively) in the SIM mode [23][24][25]. Thus, we have found that neither glucuronide nor sulfate was detected in the urine samples hydrolyzed for 6 h. This suggests that the glucuronides and sulfates were completely hydrolyzed within 6 h under these conditions.…”

Modeling of SiGe Devices Using a Self-Consistent Full-Band Device Simulator Which Properly Takes into Account Quantum-Mechanical Size Quantization and Mobility Enhancement

“…On the other hand, while there have been several experimental efforts to understand hole transport in inversion layers [1,2,3,4,5,6,7,8,9] and quantum wells [10], similar significant theoretical studies on hole transport have been few and far between. These studies can be categorized in many different ways but they can be classified broadly into those dealing with:…”