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
Website: @unf

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Fish Tissue

Classification: Biological tissue -> fish

Citations 6

"Comparison Of Digestion Methods For The Determination Of Selenium In Fish Tissue By Cathodic Stripping Voltammetry"
Anal. Chim. Acta 2000 Volume 408, Issue 1-2 Pages 97-102
David F. Lambert and Nicholas J. Turoczy

Abstract: A certified reference material (NIST-RM-50 Albacore Tuna) was analyzed for selenium by cathodic stripping voltammetry (CSV), after digestion of the material by a number of methods that avoid the use of perchloric acid. The digestion techniques tested included wet and dry ashing methods, oxygen bomb digestion, ultraviolet (UV) digestion, and methods involving elevated pressure. The only method that reliably produced results that agreed with the certified value for selenium in the reference material was the combination wet/dry ashing method incorporating elevated pressure recommended by the Association of Official Analytical Chemists (AOAC) for determination using hydride generation atomic absorption spectrometry (AAS). Recoveries using the other methods were low and variable, apparently because of incomplete destruction of organic matter and losses caused by volatilisation of selenium.
Selenium Voltammetry Sample preparation Sample preparation Sample preparation Sample preparation Sample preparation Spectrophotometry Reference material Method comparison Standard method

"Distillation, Online RP C18 Preconcentration And HPLC-UV-PCO-CVAAS As A New Combination For The Determination Of Methylmercury In Sediments And Fish Tissue"
Fresenius J. Anal. Chem. 1997 Volume 357, Issue 4 Pages 439-441
Ralf Eiden, Falf Falter, Barbara Augustin-Castro, Heinz Friedrich Scholer

Abstract: Distillation as a way of sample digestion has been combined with on-line RP C18 pre-concentration and HPLC-UV-PCO-CVAAS (high performance liquid chromatography - ultra violet - post column oxidation - cold vapor atomic absorption spectrometry) for the determination of methylmercury at background levels in sediments, soils and fish tissue. To prove the accuracy of this method, it was applied to sediment and fish tissue reference materials. The results correspond with the reference values within their error ranges. Excellent recoveries (92-95%) were obtained for the sediment samples by means of the standard addition method. The standard deviations of the sediment samples were within an acceptable range (7.2-12.5%), those of the fish samples were substantially lower (3.4-5.0%). The detection limit is 0.04 ng/g for 1 g sample weight.
Methylmercury ion HPLC Spectrophotometry C18 UV reactor Preconcentration Volatile generation Speciation Volatile generation Photochemistry

"Quantitation Of DNA And RNA In Crude Tissue Extracts By Flow Injection Analysis"
Anal. Biochem. 1991 Volume 199, Issue 1 Pages 137-141
Elaine M. Caldarone and Lawrence J. Buckley

Abstract: An automated two-dye flow injection analysis system to quantitate DNA and RNA in crude extracts of tissues is described. The method uses the fluorochrome dyes ethidium bromide and Hoechst 33258. DNA concentration is determined directly from its fluorescence in Hoechst dye. RNA is estimated from fluorescence in ethidium bromide after subtraction of the fluorescence due to DNA. This method has several advantages: a simple extraction procedure, a low detection limit (0.01 µg DNA and 0.10 µg RNA), automation, and a high sample throughput. Tissue was extracted with N-dodecanoylsarcosine (I) solution in Tris - EDTA buffer solution to give a final I concentration. in the supernatant solution of 0.1%. A diagram of the flow injection system is presented. DNA was determined from its fluorescence at 458 nm with 4-~5-(4-methylpiperazin-1-yl)[2,5'-bi-1H-benzimidazol]-2'-yl~phenol (excitation at 356 nm), and RNA from its fluorescence at 600 nm with homidium bromide (excitation at 525 nm). A DNA - homidium bromide calibration graph was also constructed and used to correct the RNA fluorescence for the presence of DNA. The detection limits were 0.01 µg for DNA and 0.1 µg for RNA. The method was applied to eggs, larvae and tissues of fish.
DNA RNA Fluorescence Spectrophotometry

"Selective Determination Of Methylmercury By Flow Injection Fast-scan Voltammetry"
Electroanalysis 1998 Volume 10, Issue 13 Pages 926-930
Rebecca Lai, Eva L. Huang, Feimeng Zhou *, David O. Wipf

Abstract: A simple flow injection system, suitable for solution flow rates at microliters-per-minute, was combined with fast-scan voltammetry for selective determination of MeHg+. A thin Hg film was formed at a Pt microelectrode prior to the measurement. Detection of MeHg+ is carried out by measuring the oxidation of MeHg radicals that were generated at the Hg microelectrode. At slow scan rates, the electrogenerated MeHg radicals undergo a follow-up dimerization reaction to form M2Hg2 (ErCi2 mechanism). At fast scan rates, MeHg radicals can be quantitatively reoxidized (reversible electron-transfer). Optimization of the experimental conditions of the system was performed based on studies of the relationship between the scan rate and the dimerization rate of the MeHg radical. Under optimized conditions, detection level of sub-nanomole was obtained with a sample consumption <10 µL, and the concentration. detection limit for MeHg+ at 50 V/s was estimated to be ~0.56 µM. To demonstrate the applicability of this method to automatic analysis, repetitive fast-scan cyclic voltammetry was conducted in conjunction with multiple sample injections. Determination of MeHg+ in the presence of excess inorganic Hg was also conducted. This approach to MeHg+ determination was successfully applied to the analysis of elevated dogfish muscle samples.
Methylmercury ion Voltammetry Electrode Electrode Speciation Optimization Apparatus

"Simultaneous Determination Of Ascorbic Acid And Dehydroascorbic Acid In Fish Tissues By High Performance Liquid Chromatography"
J. Chromatogr. B 1995 Volume 667, Issue 2 Pages 355-357
Takafumi Ito, Hisashi Murata, Yoshihide Yasui, Morimasa Matsui, Tadashi Sakai,* and Kiyoshi Yamauchi

Abstract: An high performance liquid chromatographic method with post-column derivatization has been developed for the simultaneous determination of ascorbic acid (AA) and dehydroascorbic acid (DHAA) in fish tissues. Extracted AA and DHAA were separated by a Shim-pack SCR-1O1H column within 20 min, reacted with sodium hydroxide containing sodium borohydride and monitored at 300 nm. The detection limits for both AA and DHAA were 0.1µg/ml.
Ascorbic acid dehydroascorbic acid HPLC Spectrophotometry Post-column derivatization

"Multivariate Statistical Analyses Of Some Selected Chemical And Physical Freshness Indicators Of Fish Muscle Tissue Samples"
Chemom. Intell. Lab. Syst. 1998 Volume 40, Issue 2 Pages 175-192
Derrick A. Balladin*, Dyer Narinesingh, Valerie A. Stoute and That T. Ngod

Abstract: Seventy-eight samples of [Scomberomorus brasiliensis (carite)] muscle tissue were analyzed for % fat, hypoxanthine content (determined. by a flow injection method), total volatile acids and bases, total bacterial count, and textural parameters (firmness, hardness, fracturability, cohesiveness, chewiness, and elasticity) were subjected to discriminant and factor analyzes. The apparent error rate obtained by discriminant anal. with all the parameters in the anal. was about 5.6%. However, classification was not improved (apparent error rate 6.9%) when cohesiveness and chewiness were excluded from the anal. The stepwise methods of selection (Wilks and Minresid) HxFI ranked second, and fourth when the Mahal and Maxminf methods were used. In the factor anal., using the principal component anal., five factors were extd. Factor loadings relate factor 1 (tastiness) with hypoxanthine concentration, total volatile acids and bases: factors 2, 3, 5 (texture) with the textural attributes; and factor 4 (rancidity) with the % fat content. Rotation of the reference axes showed that factors 1, 2 and 5 remained unchanged, while factors 3 and 4 were interchanged.
Fatty acids Hypoxanthine Chemometrics