A tutorial and mini-review of the ICP-MS technique for determinations of transition metal ion and main group element concentration in the neurodegenerative and brain sciences

Abstract  

New techniques in the biosciences are always welcomed and important. Reviews help in updating and disseminating information in scientific fields, especially when there are many advances such as in the vital area in neuroscience. Herein is a recent review of inductively coupled plasma mass spectrometry (ICP-MS) in the context of trace elements, relating to neurodegenerative diseases. The accurate determination of such elemental distributions in Alzheimer’s disease, Parkinson’s disease, etc. allows for a better understanding of such diseases and relates to the sensitivity and scope of the ICP-MS technique. The elements detected are often “trace” and can be analyzed for both body tissues and fluids. We discuss the practical use of ICP-MS. This includes the explanations of the instrumental setup, elements and their detection limits, a brief comparison of ICP-MS with other inorganic analysis instruments, sample preparation, and the analysis method. Next, we discuss neurodegenerative disease and metal ion analysis with ICP-MS. This includes introductions to neurodegenerative diseases, tissue analysis, fluid analysis, and bioimaging of metals in brain tissue samples, and protein analysis application with metals and ICP-MS, broken down into the subtopics of (1) isotope dilution analysis, (2) related immunoassay techniques, and (3) hyphenated instrumental applications. This article is meant to be a primer for a synthetic chemist interested in utilizing this technique and is current through the middle of 2010.     

An X-Ray Analysis on Restricted Rotational Isomers of 2-Thioxo-4-oxazolidinone

The thermodynamically more stable diastereomeric rotational isomer I, of 3-(o-tolyl)-5-methyl-2-thioxo-4-oxazolidinone, which is first crystallized out in solution, shows that the ortho methyl substituent is cisoid to the methyl group of the hetero ring, and the thermodynamically less stable isomer II, crystallized later, has both methyl groups in transoid conformation, as is found in X-ray studies. The carbonyl and thiocarbonyl bonds are found to be longer in isomer II than in isomer I, which is attributed to the favored conjugation interaction of carbonyl, thiocarbonyl groups with the lone pair electrons of nitrogen, that may cause the lessened stability of isomer II.     

Multivariable state-feedback self-tuning controllers ∗

This paper describes a state-space approach for self-tuning control of a class of multivariable stochastic systems having the same number of inputs as outputs. A multivariable state-feedback self-tuning controller, based on pole-assignment concepts, is derived. The developed multivariable self-tuner can be applied to stable/unstable and minimum/non-minimum phase linear time-invariant multivariable systems. A multivariable reduced-order self-tuner and a state-feedback minimum-variance self-tuner are also derived. The simplicity and flexibility of the proposed state-space approach facilitate the practical applications of self-tuning control concepts to real systems     

Development of a new and practical route to chiral 3,4-disubstituted cyclopentanones: asymmetric alkylation and intramolecular cyclopropanation as key C-C bond-forming steps

An efficient and practical asymmetric synthesis of (+)-trans-3-hydroxymethyl-4-(3-fluorophenyl)cyclopentanone (1) is described. An asymmetric Mo-catalyzed alkylation reaction was used to establish the first stereocenter and a Cu-catalyzed intramolecular diastereoselective cyclopropanation reaction was used to set the second stereocenter. The last step involved a one-pot ring-opening/deprotection/hydrolysis/decarboxylation sequence that furnished the desired product in good yield.