University of North Florida
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Stuart Chalk, Ph.D.
Department of Chemistry
University of North Florida
Phone: 1-904-620-1938
Fax: 1-904-620-3535
Email: schalk@unf.edu
Website: @unf

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Petr Rychlovsky

Abbrev:
Rychlovsky, P.
Other Names:
Petr Rychlovský
Address:
Institute of Analytical Chemistry, Academy of Sciences of the Czech Republic, Vídeská 1083, Prague 4, Czech Republicb Charles University of Prague, Department of Analytical Chemistry, Albertov 2030, Prague 2, Czech Republic
Phone:
NA
Fax:
+420-2-24913538

Citations 6

"Electrochemical Selenium Hydride Generation With In Situ Trapping In Graphite Tube Atomizers"
Spectrochim. Acta B 2003 Volume 58, Issue 5 Pages 919-930
Jan Síma and Petr Rychlovský

Abstract: A manifold coupling continuous electrolytic hydride generation of volatile hydrides with atomization in graphite tube atomizers after in situ collection was used for Se(IV) determination. Laboratory-made thin-layer flow-through cells with lead wire (cell I) and granular lead (cell II) as the cathode material were used as the electrolytic generators of volatile selenium hydride. The automatic sampling equipment of the graphite atomizer, with an untreated fused silica capillary, was used both for the introduction of volatile hydride into the atomizer and for pretreatment of the graphite furnace surface with a palladium modifier. The influence of the experimental parameters on the analytical signal was studied and optimum conditions for selenium determination were found. The optimum experimental parameters for hydride generation were: catholyte (1 mol L-1 HCl)/anolyte (2 mol L-1 H2SO4) flow rate of 2.0 mL min-1; applied generation current of 1.2 A (cell I) and 0.8 A (cell II); and carrier gas flow rate of 40 (cell I) and 70 mL min-1 (cell II). The hydride generated was collected in the graphite tube (pre-treated with 5 µg of Pd reduced at 800°C) at a temperature of 400°C for 30 s. The overall efficiency of H2Se electrochemical generation, transport and collection was 71±7% for cell I and 80±5% for cell II. The results for electrochemical generation of H2Se (cell II) (absolute limit of detection 50 pg, 3s criterion) were compared with the original generation of H2Se using NaBH4 as a reduction agent (absolute limit of detection 30 pg) and with conventional liquid sampling. The repeatability at the 1.0 ng mL-1 level was better than 2.4% (relative standard deviation) for electrochemical hydride generation and better than 2.8% for chemical hydride generation.

"FIA Liquid-liquid Extraction Spectrophotometric Determination Of Phenothiazine Derivatives In Pharmaceuticals"
Lab. Rob. Autom. 1996 Volume 8, Issue 4 Pages 213-219
Petr Rychlovský*, Irena Nemcová, Hana Mísarová, Martina Zanátová

Abstract: Ground tablets were dissolved in water, filtered and portions (1 ml) of the resulting solution were injected into a stream (1 ml/min) of Britton-Robinson buffer of pH 3.4, which merged with a stream (0.2 ml/min) of 80 µM-Chromazurol S (Merck), then with a CHCl3 stream (0.7 ml/min) in a segmentor (0.4 mm i.d.) and passed through a PTFE extraction coil (160 cm x 0.5 mm i.d.). The flow then passed through a phase separator with a PTFE membrane. The organic phase (0.35 ml/min) passed through a 30 µL flow cell where chlorpromazine (I), diethazine (II) and fluphenazine (III) were detected at 503, 505 and 497 nm, respectively. Calibration graphs were linear up to 10.7, 10.1 and 15.3 µg/ml I, II and III, respectively, and the corresponding detection limits were 0.11, 0.04 and 0.13 µg/ml. The RSD (n = 10) at 8 µg/ml were 1.7-2.3% for the three analytes. Recoveries are not given. Determinations in tablets gave identical results to those obtained by a Czech standard method. The sample throughput was 15/h. The proposed extraction spectrophotometric determination of phenothiazine derivatives is based on the formation of ion associates of these derivatives with chromazurol S. The determination is carried out by flow-injection analysis (FIA). Teflon separators constructed in the laboratory were tested. Three derivatives of phenothiazine; chlorpromazine, diethazine, and fluphenazine were analyzed as the substances and in pharmaceutical form. The method provides correct and reproducible results. A very low detection limit and determination limit were attained (for diethazine, e.g., 0.04 g mL-1 and 0.14 g mL-1), so that the proposed method could also be used for monitoring small pharmaceutical concentrations. The frequency of analysis is 15 samples per hour.
Chlorpromazine Pharmaceutical Spectrophotometry Sample preparation Standard method Method comparison Teflon membrane Extraction Organic phase detection Phase separator

"Design Of A Combined Cell For The Electrochemical Generation Of Volatile Compounds In Atomic Absorption Spectrometric Method"
Chem. Listy 1998 Volume 92, Issue 8 Pages 676-679
J. Sima and P. Rychlovsky

Abstract: The construction, testing, and evaluation of the application, combining an electrochemical generator of hydrides and separator of gaseous and liquid phases into one combined cell operating both in CFA and FIA regimes, are described. Arsenic was chosen for testing as a commonly determined hydride-forming element often described in literature.
Arsenic Spectrophotometry Volatile generation Electrochemical product generation Phase separator

"The Use Of A Membrane Gas-liquid Separator For Flow Injection Hydride Generation Atomic Absorption Spectrometry Online Speciation And Determination Of Arsenic(III) And Arsenic(V)"
Collect. Czech. Chem. Commun. 1998 Volume 63, Issue 12 Pages 2027-2035
Milan KRENZELOK and Petr RYCHLOVSKY

Abstract: This method employs a membrane gas-liq. separator and the hydride generation technique in the FIA AAS method for speciation of As(V) and As(III). The gas-liq. membrane separator achieves high measurement sensitivity and shows a very fast response (short delay time) because of its min. dead volume Conditions were optimized for the determination of arsenic by the flow injection hydride generation atomic absorption spectrometry method using this membrane separator. An app. was proposed for online speciation of both As(V) and As(III). Several reduction systems were used for reduction of As(V) to As(III) in the online arrangement. The best results were obtained using solution of 15 g KI in 100 mL of 6 M HCl at the reaction coil temperature 60°C. A detection limit of 150 pg for As(III), 80 pg for As(III + V) and sampling rate of 25 samples per h were reached.
Arsenic(3+) Arsenic(5+) Spectrophotometry Mass spectrometry Membrane Phase separator Volatile generation Speciation Optimization Heated reaction

"Comparison Of Hydride Generator/gas-liquid Phase Separator Systems For Continuous Hydride Generation In Atomic Absorption Spectrometry"
Collect. Czech. Chem. Commun. 1998 Volume 63, Issue 2 Pages 164-181
Milan KRENZELOK, Petr RYCHLOVSKY

Abstract: A comparison of five kinds of hydride generator/gas-liq. phase separator systems used in the hydride generation in AAS is made. These systems are also compared with a newly designed type of separator. Optimum working conditions were tested and basic characteristics were measured for all the types of systems. The basic criteria for comparison of the systems were the measuring sensitivity, reproducibility and detection limit for the given system. Additional comparison criteria were the anal. frequency achieved, applicability of the given separator for flow injection measurements and economic criteria.
Spectrophotometry Phase separator Optimization Apparatus Volatile generation

"Application Of A Heated Electrospray Interface For On-line Connection Of The AAS Detector With HPLC For Detection Of Organotin And Organolead Compounds"
Anal. Bioanal. Chem. 2002 Volume 374, Issue 5 Pages 955-962
P. Rychlovský, P. Černoch, M. Skleničková

Abstract: A heated electrospray interface that affords high sensitivity and long-term signal stability for AAS detection of metal-containing analytes in organic or organic-water solvents after HPLC separation is described. The vitreous body of the electrospray interface is externally heated above the boiling point 4 the solvent and quartz furnace AAS is used for detection. Interface working conditions were optimized with a full experimental design for the detection of tin- (tetramethyl-, tetraethyl-, tetrabutyl-, and tetrapentyltin, tributyltin chloride, dibutyltin dichloride, and butyltin trichloride) and lead- (tetraethyl- and tetraphenyllead) containing compounds in the column eluate. The heated electrospray interface enables use of a wide range of flow rates - from 50 to 1000 µL min-1. The measurement sensitivity and detection limit achieved were compared with those obtained by use of the thermospray interface and post-column conversion of the organotin compounds to gaseous hydrides. The detection limits for the low-molecular weight species of the homologous series (2.8±0.1 ng (140±5 ng mL-1) for tetramethyltin and 3.1±0.2 ng (155±10 ng mL-1) for tetraethyltin) were obtained approximately one order of magnitude lower than those obtained by use of the thermospray interface. With this HPLC-ES-QRAAS system the tributyltin content of BCR reference material 477, mussel tissue. was analyzed. This system was also applied to analysis of tetraethyllead in gasoline samples.
Speciation