MIP-based Sensors Research Articles

MIP-based solid phase extraction cartridges combined with MIP-based sensors for the detection of microcystin-LR

Microsystin-LR is one of the most widespread and dangerous toxins produced by the freshwater Cyanobacteria. The contamination of water supplies with microcystin-LR has been reported in several areas around the world and the development of an easy-to-use, rapid, robust and inexpensive sensor for this toxin is urgently required. In this work an artificial receptor for microcystin-LR was synthesised using the technique of molecular imprinting. The composition of the molecularly imprinted polymer (MIP) was optimised using computer modelling. The synthesised polymer was used both as a material for solid-phase extraction (SPE) and as a sensing element in a piezoelectric sensor. Using the combination of SPE followed by detection with a piezoelectric sensor the minimum detectable amount of toxin was 0.35 nM. The use of MIP–SPE provided up to 1000 fold pre-concentration, which was more than sufficient for achieving the required detection limit for microcystin-LR in drinking water (1 nM). This work is the first example where the same MIP receptor has been used successfully for both SPE and the corresponding sensor.

Electrochemical Sensors Based on Molecularly Imprinted Polymers

Over the past two decades, molecularly imprinted polymers (MIPs) have attracted broad interest from scientists engaged in sensor development. This attention can be explained by the serious potential advantages of using MIPs in place of natural receptors and enzymes such as their superior stability, low cost and easy preparation. This review encompasses recent achievements in molecular imprinting related to the area of sensor technology. Since electrochemical biosensors dominate the market and due to specific requirements of this journal, the emphasis of this review will be on the development of electrochemical MIP sensors. The problems associated with application of imprinted polymers in sensors are highlighted and possible solutions indicated. The commercial potential of MIP-based sensors is analyzed in the expectation that they can offer improved performance in the analytical market place.

Electrochemical Sensors Based on Molecularly Imprinted Polymers

Over the past two decades, molecularly imprinted polymers (MIPs) have attracted broad interest from scientists engaged in sensor development. This attention can be explained by the serious potential advantages of using MIPs in place of natural receptors and enzymes such as their superior stability, low cost and easy preparation. This review encompasses recent achievements in molecular imprinting related to the area of sensor technology. Since electrochemical biosensors dominate the market and due to specific requirements of this journal, the emphasis of this review will be on the development of electrochemical MIP sensors. The problems associated with application of imprinted polymers in sensors are highlighted and possible solutions indicated. The commercial potential of MIP-based sensors is analyzed in the expectation that they can offer improved performance in the analytical market place.

Influence of proteinuria on long-term outcome among patients with diabetes: The evidence continues to accumulate

Molecularly imprinted polymers (MIPs) rendered selective solely by the imprinting with protein templates lacking of distinctive properties to facilitate strong target-MIP interaction are likely to exhibit medium to low template binding affinities. While this prohibits the use of such MIPs for applications requiring the assessment of very low template concentrations, their implementation for the quantification of high-abundance proteins seems to have a clear niche in the analytical practice. We investigated this opportunity by developing a polyscopoletin-based MIP nanofilm for the electrochemical determination of elevated human serum albumin (HSA) in urine. As reference for a low abundance protein ferritin-MIPs were also prepared by the same procedure. Under optimal conditions, the imprinted sensors gave a linear response to HSA in the concentration range of 20–100 mg/dm3, and to ferritin in the range of 120–360 mg/dm3. While as expected the obtained limit of detection was not sufficient to determine endogenous ferritin in plasma, the HSA-sensor was successfully employed to analyse urine samples of patients with albuminuria. The results suggest that MIP-based sensors may be applicable for quantifying high abundance proteins in a clinical setting.

97/03229 Variable flow—the quest for system energy efficiency

The increasing global reports on the occurrence of macrolide antibiotics resistance, especially erythromycin (Ery) resistant strains, suggests the possible presence of these antibiotics in the environment hence, their inclusion in the EU watchlist of water pollutants. Consequently, there is an urgent need for the development of portable and cost effective analytical sensing devices for their monitoring in water. The combination of molecularly imprinted polymer (MIP) as a sensing element with a portable electrochemical transducer such as screen printed electrode (SPE) may offer a valuable approach for the desired routine environmental monitoring. This work demonstrates the preparation of an electrochemical MIP-based sensor for Ery detection in aqueous media. Ery-selective MIP, Ery-MIP was generated directly on SPE, Ery-MIP/SPE via electrochemical polymerization of m-phenylenediamine (mPD). The optimization of sensor performance was achieved with special attention given to the selection of functional monomer, template removal, polymer thickness and incubation time. Ery-MIP/SPE sensor demonstrated the ability to discriminate target analyte against very close analogues i.e clarithromycin and azithromycin in both PBS and tap water. In addition, Ery-MIP/SPE could detect Ery down to low limits (LOD = 0.1 nM and LOQ = 0.4 nM) and exhibited good recovery in tap water. The presented analytical approach could be potentially suited and/or further developed for adequate monitoring of Ery as well as other macrolides in environmental water.