The centrifugal liquid membrane (CLM) method, designed for the rapid sample injection, was applied to the kinetic study of the complexation of palladium(II) with 2-(5-bromo-2-pyridylazo)-5-diethyaminophenol (5-Br-PADAP) in the heptane/water system. The formation rates of Pd(II)-5-Br-PADAP complex, which existed only at the heptane/water interface, could be directly measured by the CLM method co...

Serratia entomophila and Serratia proteamaculans cause amber disease in the grass grub Costelytra zealandica (Coleoptera: Scarabaeidae), an important pasture pest in New Zealand. Larval disease symptoms include cessation of feeding, clearance of the gut, amber coloration, and eventual death. A 115-kb plasmid, pADAP, identified in S. entomophila is required for disease causation and, when introd...

Some strains of Serratia entomophila and S. proteamaculans cause amber disease of the grass grub Costelytra zealandica (Coleoptera: Scarabaeidae). Three genes required for virulence, sepABC, are located on a large plasmid, pADAP. Sequence analysis suggests that the sepABC gene cluster may be part of a horizontally mobile region. This study presents evidence for the putative mobility of the sep ...

Serratia entomophila and Serratia proteamaculans (Enterobacteriaceae) cause amber disease in the grass grub Costelytra zealandica (Coleoptera: Scarabaeidae), an important pasture pest in New Zealand. Larval disease symptoms include cessation of feeding, clearance of the gut, amber coloration, and eventual death. A 155-kb plasmid, pADAP, carries the genes sepA, sepB, and sepC, which are essentia...

A new visual colorimetry for trace antimony(V) based on ion-pair solid-phase extraction to a PTFE-type membrane filter with bis[2-(5-chloro-2-pyridylazo)-5-diethylaminophenolato]cobalt(III) ion ([Co(5-Cl-PADAP)(2)](+)) has been developed. Experiments showed that hexachloroantimonate(V) ion (SbCl(6)(-)) was adsorbed with [Co(5-Cl-PADAP)(2)](+) to the front surface of the PTFE filter. The adsorpt...

This paper discusses the development of and proposed enhancements to a colorimetric test for the detection of uranium in biological samples such as urine. The goal of this work is to develop a technique for the detection of uranium that could: 1) be conducted rapidly and accurately; 2) would not require extensive sample preparation; 3) would not require expensive or complicated instrumentation;...

A ratiometric indicator-displacement assay (RIDA) array has been developed for the semi-quantitative colorimetric determination of chloride, bromide, and iodide anions. Determinations of these halide anions follow the displacement reaction using the chelate compound of (2-(3,5-dibromo-2-pyridylazo)-5-(diethylamino)phenol) (3,5-Br2-PADAP) and heavy metal salts as colorimetric reagent. Different ...

A new method for the simultaneous separation and determination of mercury(II) with other heavy and transition metals by ion chromatography (IC) was developed. This method involves on-column derivatization with 2,6-pyridinedicarboxylic acid (PDCA) and anion-exchange separation, followed by a post-column reaction with 2-[(5-bromo-2-pyridyl)-azo]-5-diethylaminophenol (5-Br-PADAP) to form metal–5-B...

Strains of Serratia spp. showed a high level of virulence when injected into the hemocoel of larvae Costelytra zealandica, with Serratia entomophila, S. plymuthica, and S. marcescens showing significantly higher virulence than S. proteamaculans. Toxicity was independent of the amber disease-causing plasmid pADAP, suggesting a generalized Serratia toxin.