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R D Satzger

Publications and source records attributed to R D Satzger.

13 recordsLinked to original sources
PubMed2001

The chemical interconversion of GHB and GBL: forensic issues and implications.

In this work, the interconversion of GHB and GBL in a variety of aqueous media was studied. The effects of solution pH and time were determined by spiking GHB or GBL into pure water and buffered aqueous solutions, and determining the GHB and GBL contents at various time intervals. The degree of GBL hydrolysis to GHB was determined for several commercial aqueous-based GBL products, and further studied as a function of time. The effects of temperature and time were also determined for five commercial beverages spiked with GHB or GBL. GHB and GBL contents were determined using high performance liquid chromatography (HPLC). GHB and/or GBL confirmations were made using gas chromatography-mass spectrometry (GC-MS) and/or infrared spectroscopy (IR). Solution pH, time, and storage temperature were determined to be important factors affecting the rate and extent of GBL hydrolysis to GHB. Under strongly alkaline conditions (pH 12.0), GBL was completely converted to GHB within minutes. In pure water, GBL reacted to form an equilibrium mixture comprising ca. 2:1 GBL:GHB over a period of months. This same equilibrium mixture was established from either GHB or GBL in strongly acidic solution (pH 2.0) within days. A substantial portion of GBL (ca. 1/3) was hydrolyzed to GHB in aqueous-based GBL products, and in spiked commercial beverages, after ambient storage for a period ranging from several weeks to several months. Heat increased and refrigeration decreased the rate of GBL hydrolysis relative to ambient conditions. These studies show that hydrolysis of GBL to GHB does occur in aqueous-based solutions, with samples and time frames that are relevant to forensic testing. Implications for forensic testing and recommendations are discussed.

4-Butyrolactone↗
PubMed1997

Detection of clenbuterol in bovine retinal tissue by high-performance liquid chromatography with electrochemical detection.

A method for the detection of the beta-agonist drug clenbuterol in bovine retinal tissue has been developed. The extraction procedure involves sonication and centrifugation, followed by the addition of ethylenediaminetetraacetic acid (EDTA) to the supernatant. The pH of the supernatant is then brought to 12.2, which is then allowed to sit for 2 h. This is followed by a diethylether extraction. The diethylether extract is dried under nitrogen and the residue is dissolved in 1% formic acid. The quantitation of clenbuterol was accomplished by high-performance liquid chromatography with electrochemical detection. The electrochemical detector was an amperometric detection. The detector was set in the pulsed mode. The oxidizing potential of a carbon electrode was 1.3 V vs. a Ag/AgCl reference electrode and was pulsed to a reduction potential of 2.0 V vs. a Ag/AgCl reference electrode. The limit of detection for this method was 5 ng/ml of clenbuterol (S/N = 3). Typical spiked recoveries are 75%.

Adrenergic beta-Agonists↗
PubMed1997

Determination of anabolic steroids by HPLC with UV-vis-particle beam mass spectrometry.

This paper describes a general screening method for the determination of anabolic steroids in oil-based injectables, water suspensions, dietary supplements, and herbal drugs marketed in the form of capsules or tablets. The compounds are extracted into methanol, separated on a reversed-phase column with an acetonitrile-water gradient, and detected by using an ultraviolet visible (UV-vis) photodiode array detector and a particle beam mass spectrometric detector coupled in series. Identification is based on retention time, UV-vis spectra, and mass spectra. Mass spectral confirmation is accomplished by matching with a standard when available and by comparison with an electron impact mass spectra library that is either commercially available or generated in our laboratory. The tandem arrangement of the detectors provides qualitative and quantitative information from a single experiment by fully utilizing the inherent advantages associated with each detector. This method is applicable to all the anabolic steroids encountered in this laboratory so far.

Anabolic Agents↗
PubMed1995

Determination of ephedrine compounds in nutritional supplements by cyclodextrin-modified capillary electrophoresis.

Capillary electrophoresis was utilized for the separation, identification, and quantitation of ten stereoisomers in the ephedrine family. Chiral discrimination was accomplished through the use of hydroxypropyl-beta-cyclodextrin, and separation was enhanced at pH 2 in the presence of tetramethylammonium chloride and sodium dodecyl sulfate. Calibration plots of the ephedrines were linear over the range 4-100 micrograms/ml. This method was used in the analysis of nutritional supplements that contain Ma Huang, a Chinese herbal preparation that is made from plants in the genus Ephedra.

Cyclodextrins↗
PubMed1983

Determination of lead in bonemeal by differential pulse anodic stripping voltammetry using a hydrochloric acid solubilization.

A safe, rapid method is described for the determination of lead in bonemeal. This method uses a hydrochloric acid solubilization performed under pressure followed by determination by differential pulse anodic stripping voltammetry. This provides an alternative to a nitric-perchloric acid wet ash. Data obtained using both methods are compared. The mean recovery of a standard Pb spike was 99.2 +/- 7%. The concentration of Pb in bonemeal ranged from 1.0 to 15.6 micrograms/g.

Biological Products↗
PubMed1982

Determination of background levels of lead and cadmium in raw agricultural crops by using differential pulse anodic stripping voltammetry.

A method is described for the simultaneous determination of ultratrace levels of lead and cadmium in selected agricultural crop samples by differential pulse anodic stripping voltammetry. Samples are dry ashed at high temperature with H2SO4 as an ashing aid. Techniques are described to control the lead and cadmium blank levels of 2 ng and 0.4 ng, respectively. Typical relative standard deviations for the crop analyses are 13% at 100 ng/g and 25% at 10 ng/g for lead, and 5% at 100 ng/g and 10% at 10 ng/g for cadmium. The lowest quantifiable level, based on 3 g dry sample, is 2 ng/g for lead and 1 ng/g for cadmium. Recovery studies, precision studies, and analyses of NBS Standard Reference Materials demonstrate the accuracy and reproducibility of this technique. A summary of results for over 1700 crop samples is reported.

Cadmium↗
PubMedDate not supplied

Development of a quality assurance program for determination of ultratrace background levels of lead and cadmium in raw agricultural crops by differential pulse anodic stripping voltammetry.

Data on the background levels of lead and cadmium in the food supply are essential in order to establish a baseline from which to evaluate the extent of contamination in transport, processing, industrial atmospheric particulate fallout, and soil treatment (e.g., fertilizers, sewage sludge, etc.). This requires the establishment of site selection and sampling criteria as well as the development of a rigorous analytical method capable of performing routine analyses of Pb and Cd at ultratrace levels. The method used in this study, which was published previously, was designed to provide high sample throughput with minimal contamination. This involved control and measurement of blank levels and the establishment of quality control procedures to maintain confidence in the accuracy and precision of the method.

Cadmium↗
PubMedDate not supplied

Determination of 4-hexylresorcinol in crab meat.

A method is described for determining 4-hexylresorcinol in crab meat. 4-Hexylresorcinol is used to prevent melanosis in shrimp, and the same use has been proposed for crab meat. Because 4-hexylresorcinol may be added illegally to crab meat as a preservative, consumer protection requires that residues of the compound be monitored in crab meat. 4-Hexylresorcinol is extracted from crab meat with acetonitrile. After dilution with water, the extract is passed through a C18 solid-phase extraction column and 4-hexylresorcinol is eluted from the column with ethanol. The compound is determined by reversed-phase liquid chromatography with diode array detection at 206 nm. Limit of quantitation is 1.0 microgram/g. Mean recovery in the range 1-20 micrograms/g is 89%, with a relative standard deviation of 6.3.

Animals↗