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The coastal zone is one of the most important features on the earth’s surface; therefore, it is imperative to extract the coastline, a representative coastal zone feature with high quality. Previou...

A new system for the determination of nucleic acid by rare earth metallic porphyrin of [tetra-(3-methoxy-4-hydroxyphenyl)]–Tb3+ [T(3-MO-4HP)–Tb3+] porphyrin as fluorescence spectral probe has been developed in this paper. Nucleic acid can enhance the fluorescence intensity of the T(3-MO-4HP)–Tb3+ porphyrin in the presence of bis(2-ethylhexyl)sulfosuccinate sodium salt(AOT) micelle. In pH 8.00 Tris–HCl buffer solution, under optimum conditions, the enhanced fluorescence intensity is in proportion to the concentration of nucleic acids in the range of 0.05–3.00 µg mL−1 for calf thymus DNA (ct DNA) and 0.03–4.80 µg mL−1 for fish sperm DNA(fs DNA). Their detection limits are 0.03 and 0.01 µg mL−1, respectively. In addition, the binding interaction mechanism between T(3-MO-4HP)–Tb3+ porphyrin and ct DNA is also investigated by resonance scattering and fluorescence spectra. The maximum binding number is calculated by molar ratio method. The new system can be used for the determination of nucleic acid in pig liver, yielding satisfactory results. Copyright © 2009 John Wiley & Sons, Ltd.

A novel method for the determination of proteins was developed, based on the enhancement of fluorescence with 4-chloro-(2'-hydroxylophenylazo)rhodanine-Ti(IV) [ClHARP-Ti(IV)] complex as a fluorescence probe. The excitation and emission wavelengths of the system were 335 nm and 376 nm, respectively. The presence of bis(2-ethylhexyl)sulphosuccinate sodium salt (AOT) microemulsion greatly increased the sensitivity of the system. Under optimal conditions, four kinds of proteins, including bovine serum albumin (BSA), human serum albumin (HSA), egg albumin (Ova), and gamma-globin (gamma-G) were studied. The detection limits were 0.182 microg/mL for BSA, 0.0788 microg/mL for HSA, 0.216 microg/mL for Ova and 0.484 microg/mL for gamma-G. The linear ranges of the calibration were 0-12.0, 0-10.0, 0-18.0 and 0-18.0 microg/mL, respectively. The method possessed high sensitivity, good selectivity and was applied to the analysis of protein in milk powder and cornmeal with satisfactory results.

Inspired by a reactivity study between sodium trimetaphosphate (P3m) and amino acids in prebiotic chemistry, a one-step reaction with efficient purification procedure in aqueous media has been developed for the synthesis of N-phosphono-amino acids (NPAA). P3m was used to phosphorylate amino acids to NPAA with yields of 60∼91%. The by-products, inorganic polyphosphates, were recycled to regenerate the phosphorylation reagent P3m.