Electrochemically synthesized polymers in molecular imprinting for chemical sensing

This critical review describes a class of polymers prepared by electrochemical polymerization that employs the concept of molecular imprinting for chemical sensing. The principal focus is on both conducting and nonconducting polymers prepared by electropolymerization of electroactive functional monomers, such as pristine and derivatized pyrrole, aminophenylboronic acid, thiophene, porphyrin, aniline, phenylenediamine, phenol, and thiophenol. A critical evaluation of the literature on electrosynthesized molecularly imprinted polymers (MIPs) applied as recognition elements of chemical sensors is presented. The aim of this review is to highlight recent achievements in analytical applications of these MIPs, including present strategies of determination of different analytes as well as identification and solutions for problems encountered

Recognition of conformational changes in β-lactoglobulin via molecularly imprinted thin films

Pathogenesis in protein conformational diseases is initiated by changes in protein secondary structure. This molecular restructuring presents an opportunity for novel shape-based detection approaches, as protein molecular weight and chemistry are otherwise unaltered. Here we apply molecular imprinting to discriminate between distinct conformations of the model protein β-lactoglobulin (BLG). Thermal- and fluoro-alcohol-induced BLG isoforms were imprinted in thin films of 3-aminophenylboronic acid on quartz crystal microbalance chips. Enhanced rebinding of the template isoform was observed in all cases when compared to the binding of nontemplate isoforms over the concentration range of 1−100 μg mL-1. Furthermore, it was observed that the greater the changes in the secondary structure of the template protein the lower the binding of native BLG challenges to the imprint, suggesting a strong steric influence in the recognition system. This feasibility study is a first demonstration of molecular imprints for recognition of distinct conformations of the same protein

Proving Atomicity: An Assertional Approach

Atomicity (or linearizability) is a commonly used consistency criterion for distributed services and objects. Although atomic object implementations are abundant, proving that algorithms achieve atomicity has turned out to be a challenging problem. In this paper, we initiate the study of systematic ways of verifying distributed implementations of atomic objects, beginning with read/write objects (registers). Our general approach is to replace the existing operational reasoning about events and partial orders with assertional reasoning about invariants and simulation relations. To this end, we define an abstract state machine that captures the atomicity property and prove correctness of the object implementations by establishing a simulation mapping between the implementation and the specification automata. We demonstrate the generality of our specification by showing that it is implemented by three different read/write register constructions (the message-passing register emulation of Attiya, Bar-Noy and Dolev, its optimized version based on real time, and the shared memory register construction of Vitanyi and Awerbuch), and by a general atomic object implementation based on the Lamport\'s replicated state machine algorithm