Brain homogenate stability for stimulant drugs.

Brain can be a useful specimen for toxicology testing as it is a protected and isolated organ with lower metabolic activity than other tissues, but there is currently no published data supporting the stability of stimulant drugs in prepared brain homogenates. Brain homogenates were evaluated to determine the stability of the following stimulant drugs: amphetamine, benzoylecgonine, bupropion, cocaethylene, cocaine, ephedrine, methylenedioxyamphetamine, methylenedioxymethamphetamine, methamphetamine, and phentermine. Four different homogenates were prepared at a 1:4 dilution with deionized water and fortified at 500 ng/mL of: cocaine without sodium fluoride, cocaine with 1% sodium fluoride, stimulant drugs other than cocaine without sodium fluoride, and stimulant drugs other than cocaine with 1% sodium fluoride.

Validation of the Neogen ELISA Benzodiazepine Kit using Clonazepam as the Target Molecule for Blood and Urine.

This study demonstrates the validation of a semi-quantitative method for the rapid screening of whole blood and urine specimens using clonazepam as the target molecule for the Neogen® Benzodiazepine kit. Decision points were validated at 10.0 ng/mL for whole blood and 25.

Study of Perfluorophosphonic Acid Surface Modifications on Zinc Oxide Nanoparticles.

In this study, perfluorinated phosphonic acid modifications were utilized to modify zinc oxide (ZnO) nanoparticles because they create a more stable surface due to the electronegativity of the perfluoro head group. Specifically, 12-pentafluorophenoxydodecylphosphonic acid, 2,3,4,5,6-pentafluorobenzylphosphonic acid, and (1H,1H,2H,2H-perfluorododecyl)phosphonic acid have been used to form thin films on the nanoparticle surfaces. The modified nanoparticles were then characterized using infrared spectroscopy, X-ray photoelectron spectroscopy, and solid-state nuclear magnetic resonance spectroscopy.

Moving towards fast characterization of polymorphic drugs by solid-state NMR spectroscopy.

Solid-state nuclear magnetic resonance (SS-NMR) spectroscopy has become a common technique to study polymorphism in pharmaceutical solids at high-resolution. However, high-throughput application of high resolution SS-NMR spectroscopy is severely limited by the long H spin-lattice relaxation (T) that is common to solid phase compounds. Here, we demonstrate the use of paramagnetic relaxation reagents such as chromium (III) acetylacetonate (Cr(acac)) and nickel (II) acetylacetonate (Ni(acac)) for fast data acquisition by significantly reducing the T value for carbamazepine Forms I, II, III, and dihydrate, cimetidine Forms A and B, nabumetone Form I, and acetaminophen Form I polymorphs.