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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Nucleic acids

@ ChemSpider@ NIST@ PubChem

Citations 5

"Spectrophotometric Determination Of PK(a) Values Based On A PH Gradient Flow Injection System"
Anal. Chim. Acta 2000 Volume 408, Issue 1-2 Pages 135-143
Javier Saurina, Santiago Hernández-Cassou, Romà Tauler and Anna Izquierdo-Ridorsa

Abstract: This paper describes a pH gradient flow injection method for fast spectrophotometric determination of acidity constants. The flow injection system consists of a three-channel manifold in which the sample bolus is injected between acidic and basic zones. Therefore, the front of the flow injection peak is made acidic while the tail of the peak is alkalinized, and consequently, a pH gradient from acidic to basic medium is generated along the flow injection peak in an easy and reproducible way. The whole procedure is composed of two steps; first, the in situ determination of the pH gradient profile by using a standard compound with a known pK(a) value, and second, this pH gradient profile is used to calculate the pK(a) of an unknown compound. An alternating least squares multivariate curve resolution method is used in both steps to resolve the concentration profiles of the acidic and basic species in the standard and in the unknown samples which are the basis of the calculations. The method is tested using several nucleic acid components. An additional advantage of the proposed method is that no pH experimental measurement is needed for the fast determination of pK(a) values. Results obtained using the proposed procedure are consistent with those listed in the literature.
Water Spectrophotometry pH gradient Titrations Multivariate calibration

"Trace Measurements Of Nucleic Acids Using Flow Injection Amperometry"
Anal. Chim. Acta 1996 Volume 319, Issue 3 Pages 347-352
Joseph Wang*, Liang Chen and Manuel Chicharro

Abstract: The FIA method for the determination of nucleic acids was based on the oxidation of the bound guanine moiety at an untreated C paste electrode. A 20 µL sample was injected into a phosphate buffer carrier stream (0.75 ml/min) at pH 7.5 and transported to the detection cell which was equipped with a thin-layer C paste electrode at 1 V vs. Ag/AgCl. Linear calibration graphs were obtained for up to 10 ppm of double-stranded DNA, single-stranded DNA and transfer (t)-RNA and detection limits were 460, 540 and 750 pg, respectively. The RSD (n = 30) for the determination of 10 mg/l double-stranded DNA and single-stranded DNA and 14 mg/l t-RNA were 1.9-2.7%.
Amperometry

"Nucleic Acid Quantitation By Continuous-flow Fluorimetry"
Anal. Biochem. 1986 Volume 154, Issue 2 Pages 638-642
Michael G. Murray and Herbert E. Paaren

Abstract: A solution of the fluorochrome (ethidium bromide or Hoechst 33258 dye) in 10 mM Tris - HCl (pH 7.5) - 10 mM NaCl - 1 mM EDTA is pumped through a pulse-damping coil to an injection valve, equipped with a constant-volume fill loop. The sample solution is injected into the fluorochrome stream and the mixture is pumped to a fluorescence detector. Samples (5 µL) ranging in concentration from 0.05 to 40 µg mL-1 of nucleic acid can be analyzed accurately at a rate of 3 to 5 min-1. The samples can be recovered.
Fluorescence Pulse dampener

"Development Of A Multi-component Analysis System. Application And Preliminary Results Of A Comparative Study Of Cellular Metabolism In Healthy And Damaged Picea Trees From Polluted Areas"
J. Chromatogr. A 1987 Volume 393, Issue 1 Pages 97-105
V. R. Villanueva, M. Mardon, M. Th. Le Goff and F. Moncelon

Abstract: A system is described for determination of high- and low-mol.-wt. compounds in a single crude biological sample. The sample is extracted and centrifuged, and the solid containing the high-mol.-wt. compounds is analyzed by polyacrylamide-gel electrophoresis to determine the proteins, nucleic acids and polysaccharides. The supernatant solution containing the low-mol.-wt. compounds is analyzed by ion-exchange HPLC on a number of automatic analyzer.s to determine, e.g., amino-acids, polyamines, sugars, organic acids and nucleotides. A total functional analysis of the ppt. and supernatant solution is carried out by flow injection analysis. The components of the system are connected by the Spectra-Physics LABNET network to an IBM-XT microcomputer. The system has been used to study the physiological effects of acid rain on Picea needles.
Needles HPLC Computer

"High Performance Liquid Chromatography Of Bioactive Substances Using Bifunctional Fluorigenic Reagents For Derivatization. Review"
Anal. Sci. 1989 Volume 5, Issue 4 Pages 371-388
Y. OHKURA

Abstract: A review is presented of pre- and post-column derivatization methods for HPLC in which bifunctional compounds are used to react with 1,2-dioxo- or mono-oxo-compounds to yield fluorescent cyclic products. Examples are provided of applications to, e.g., aldehydes, 2-oxo-acids, catecholamines, peptides, fatty acids (including prostaglandins), nucleic acids derivatives and biogenic alcohols. (132 references).
HPLC Fluorescence Post-column derivatization Pre-column derivatization Review