A molecularly imprinted polymer for the determination of neopterin

Molecularly Imprinted Polymers for the Determination of Cancer Biomarkers

Biomarkers can provide critical information about cancer and many other diseases; therefore, developing analytical systems for recognising biomarkers is an essential direction in bioanalytical chemistry. Recently molecularly imprinted polymers (MIPs) have been applied in analytical systems to determine biomarkers. This article aims to an overview of MIPs used for the detection of cancer biomarkers, namely: prostate cancer (PSA), breast cancer (CA15-3, HER-2), epithelial ovarian cancer (CA-125), hepatocellular carcinoma (AFP), and small molecule cancer biomarkers (5-HIAA and neopterin). These cancer biomarkers may be found in tumours, blood, urine, faeces, or other body fluids or tissues. The determination of low concentrations of biomarkers in these complex matrices is technically challenging. The overviewed studies used MIP-based biosensors to assess natural or artificial samples such as blood, serum, plasma, or urine. Molecular imprinting technology and MIP-based sensor creation principles are outlined. Analytical signal determination methods and the nature and chemical structure of the imprinted polymers are discussed. Based on the reviewed biosensors, the results are compared, and the most suitable materials for each biomarker are discussed.

Raclopride-Molecularly Imprinted Polymers: A Promising Technology for Selective [11C]Raclopride Purification

In this work, we developed a novel approach to purify [¹¹C]Raclopride ([¹¹C]RAC), an important positron emission tomography radiotracer, based on tailored shape-recognition polymers, with the aim to substitute single-pass HPLC purification with an in-flow trap & release process. Molecular imprinting technology (MIT) applied to solid phase extraction (MISPE) was investigated to develop a setting able to selectively extract [¹¹C]RAC in a mixture containing a high amount of its precursor, (S)-O-Des-Methyl-Raclopride (DM-RAC). Two imprinted polymers selective for unlabeled RAC and DM-RAC were synthesized through a radical polymerization at 65 °C using methacrylic acid and trimethylolpropane trimethacrylate in the presence of template molecule (RAC or DM-RAC). The prepared polymer was characterized by scanning electron microscopy and Fourier transform infrared spectroscopy and tested in MISPE experiments. The polymers were used in testing conditions, revealing a high retention capacity of RAC-MISPE to retain RAC either in the presence of similar concentrations of RAC and DM-RAC precursor (96.9%, RSD 6.6%) and in the presence of a large excess of precursor (90%, RSD 4.6%) in the loading solution. Starting from these promising results, preliminary studies for selective purification of [¹¹C]Raclopride using this RAC-MISPE were performed and, while generally confirming the selectivity capacity of the polymer, revealed challenging applicability to the current synthetic process, mainly due to high backpressures and long elution times.

Determination of Neopterin as a Prognostic Indicator Using Neopterin-Imprinted Cryogel Membranes

Neopterin (Neo) is thought of as a key biomarker for the diagnosis and prognosis of a wide variety of diseases associated with cellular immune response. Therefore, it has become a vital need to be able to specifically determine the Neo concentration in human serum. Molecularly imprinted cryogels have come into prominence among other affinity systems by combining advantages of Molecular Imprinting Technology (MIT) and cryogels. In this chapter, synthesis of novel Neopterin-imprinted cryogel membranes (Neo-mip), characterization studies of synthesized materials, and their use in the determination of Neo in human serum is described in detail. In addition, the evaluation of selective Neo adsorption properties of Neo-mip against competitors (Pterin and Glucose) is discussed. Neo-mip will come into prominence as important affinity materials for the selective Neo recognition in body fluids, prior to use in the health sector.