A sensitive solid-phase fluoroimmunoassay for detection of opiates in urine

An automated flow fluorometer designed for kinetic binding analysis was adapted to develop a solid-phase competitive fluoroimmunoassay for urinalysis of opiates. The solid phase consisted of polymer beads coated with commercial monoclonal antibodies (MAbs) raised against morphine. Fluorescein-conjugated morphine (FL-MOR) was used as the fluorescein-labeled hapten. The dissociation equilibrium constant (K _D ) for the binding of FL-MOR to the anti-MOR MAb was 0.23 nM. The binding of FL-MOR to the anti-MOR MAb reached steady state within minutes and was displaced effectively by morphine and other opiates. Morphine-3-glucuronide (M3G), the major urinary metabolite of heroin and morphine, competed effectively with FL-MOR in a concentration-dependent manner for binding to the antimorphine MAb and was therefore used to construct the calibration curve. The sensitivity of the assay was 0.2 ng/mL for M3G. The assay was effective at concentrations of M3G from 0.2 to 50 ng/mL, with an IC₅₀ of 2 ng/mL. Other opiates and heroin metabolites that showed >50% crossreactivity when present at 1 μg/mL included codeine, morphine-6-glucuronide, and oxycodone. Methadone showed very low crossreactivity (<5%), which is a benefit for testing in patients being treated for opiate addictions. The high sensitivity of the assay and the relatively high cutoff value for positive opiate tests allows very small sample volumes (e.g., in saliva or sweat) to be analyzed. A double-blind comparison using 205 clinical urine samples showed good agreement between this single-step competitive assay and a commercially performed enzyme multiplied immunoassay technique for the detection of opiates and benzoylecgonine (a metabolite of cocaine).     

Substituent electronic effects on the persistence and absorption spectra of (Z)-o-xylylenols. A nanosecond laser flash photolysis study

[reaction: see text] A systematic investigation on a broad set of aldehydes reveals that the lifetimes of (Z)-photoenols can be modulated by variation of the substituents. We have found that the lifetimes of (Z)-enols (in benzene) can be varied by more than 1 order of magnitude with a judicious choice of the substituents that exert mesomeric and inductive effects as, for example, in the case of pentamethylbenzaldehyde (tau = 35 ns) and dicyanomesitaldehyde (tau = 760 ns). This study thus points to the fact that the electronic factors in conjunction with hydrogen bonding stabilization can considerably broaden the uni- as well as bimolecular chemistry based on photoenolization. Further, we have shown that the photoenols exhibit dramatic shifts in their absorption properties with variation of the substituents; although the photoenols have long been considered to be colored, their absorption properties have not been heretofore comprehensively examined.     

Oxidations with IBX: benzyl halides to carbonyl compounds, and the one-pot conversion of olefins to 1,2-diketones

A variety of benzyl halides were converted to the corresponding aldehydes/ketones in respectable yields by IBX in DMSO at 65 °C. The bromohydrin reaction of olefins using NBS-H₂O in DMSO can be nicely adapted to IBX-mediated oxidation of benzyl halides in such a way that olefins are converted to the corresponding 1,2-diketones in good isolated yields in one-pot.     

SH-waves in viscoelastic heterogeneous layer over half-space with self-weight

The effect of gravity, heterogeneity and internal friction on propagation of SH-waves (horizontally polarised shear waves) in viscoelastic layer over a half-space has been studied. Using the method of separation of variables, dispersion equation has been obtained and used to recover the damped velocity of SH-waves. Both the real and imaginary parts of dispersion equation are in well agreement with the classical Love wave equation. It has been observed that heterogeneity of the medium affects the velocity profile of SH-wave significantly. Some other peculiarities have been observed and discussed in our study.     

Temperature Dependent Raman Spectroscopic Study of the Fe Doped La0.67Sr0.33MnO3 Prepared Using Ball Milling Method

Physics of the Solid State - Polycrystalline samples of La0.67Sr0.33Mn0.65Fe0.35O3 (LSMFO) were synthesized using the standard ball mill method with different calcination temperatures ranging from...     

Bioactive Penta-Coordinated Diorganotin(Iv) Complexes of Pyridoxalimine Schiff Bases

Abstract

Diorganotin(IV) complexes of an extended system derived from the condensation of pyridoxal hydrochloride with 2-amino phenol (H₂L¹), 2-amino-4-methyl phenol (H₂L²), 2-amino-4-chloro phenol (H₂L³), 2-amino-4-nitro phenol (H₂L⁴), 1-amino-2-naphthol hydrochloride (H₂L⁵) have been synthesized by the reaction of dichlorodiorganotin(IV) in a 1:1 molar ratio with these ligands. Spectral studies (IR, ¹H, ¹³C, ¹¹⁹Sn NMR) along with physical data evidenced the formation of penta-coordinated species with the ligands acting as tridentate (ONO) with oxygen occupying the axial positions, and nitrogen at one of the equatorial positions. The ligands and their organotin complexes have been evaluated for antimicrobial activity against phytopathogenic fungi Candida albicans and Aspergillus niger at 25 ± 1 °C and bacteria Bacillus subtilis, Escherichia coli, and Staphylococcus aureus at 37 ± 1 °C. The activities of the ligands have been enhanced on complexation and the results indicate that they exhibit significant antimicrobial properties.

Supplemental materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfur, and Silicon and the Related Elements to view the free supplemental file.     

Liquid-Phase and Solventless Oxidation of Cyclohexane,Benzene, and Other Hydrocarbons by Cerium(IV) Catalyzed by Iridium(III) in Acidic Medium

Oxidation of some hydrocarbons dissolved in acetic acid by cerium(IV) sulphate at 100 °C in the presence of traces of iridium(III) chloride (catalyst-substrate 1:56818 to 151515) in the solution phase resulted in good to excellent yields of corresponding carbonyl compounds. In the cases of cyclohexane and benzene, 44% and 51.8% yields of corresponding carbonyl compounds were obtained, whereas in other cases, yield ranged from 34.9 to 99.8%. Yield decreased when reactions were performed in a microwave oven by adsorbing reactants (except acetic acid) on alumina. Decrease in the yield was probably due to the high temperature generated during the course of the reaction, resulting in the loss of organics from evaporation. Conditions were optimized for the highest yields under ambient conditions.