Selective Extraction of Proteins and Other Macromolecules from Biological Samples Using Molecular Imprinted Polymers

Abstract

Background 12The determination of drugs, metabolites and biomarkers in biological samples 13 continues to present one of the most difficult challenges to analytical scientists. 14 Matrices such as plasma, serum, blood, urine or tissues for example, usually 15 contain the analyte(s) of interest at low concentration in the presence of many 16 other components which may interfere directly or indirectly with the accurate 17 determination of species and concentration. Historically, the most common 18 methods have involved some form of extraction or isolation such as liquid-liquid 19 extraction (LLE), solid phase extraction (SPE) or protein precipitation. For a 20 recent review of sample preparation methods for bioanalysis, see [1]. This 21 includes comments on costs, automation, and miniaturisation with an overall 22 focus on productivity. 23 24Accurate quantitative measurement over the last 40 years has traditionally been 25 carried out by chromatography, mainly high performance liquid chromatography 26 (HPLC) and occasionally gas chromatography (GC). Although a range of 27 detectors has been available for both, most typically, HPLC used ultraviolet (UV) 28 and GC used flame ionisation and then both have used mass spectrometry (MS). 29Sample preparation has been usually by a variant of LLE, SPE or protein 30 precipitation [2]. As the need for greater sensitivity has been a constant 31 challenge, sophisticated and more selective methods of sample preparation have 32 been explored. One of the most attractive of these has been the use of 33 immobilised antibodies [3] selectively bind the analyte, in a similar way to an antibody. Immobilized 57 antibodies can be very specific but they are inherently quite fragile molecules, 58 particularly when exposed to organic solvents, pH values of more than 2-3 units 59 from neutral and/or heat. They can also be quite time-consuming to produce, in 60 many cases requiring repeated dosing to animals, with no certainty that useful 61 antibodies will eventually be obtained. In contrast, MIPs are produced rapidly in 62 the chemistry laboratory and use well-established synthetic routes which lead to 63 comparatively lower production costs. They are more stable over a wider pH 64 range and can be used with a broader range of solvents. This potentially also 65 offers the advantage that they could be re-usable, further lowering the costs. solid phase microextraction (SPME) or ultrasonic assisted SPME [17][18][19] and 80 matrix dispersant SPME [20, 21]. MIPs which are integrated with magnetic 81 nanoparticles offers the added advantage of a simple separation using a magnet 82 following the selective template (analyte) binding/extraction step. Ding et al. 2014 83 [22] has written a recent review on surface imprinting technologies for nano-84MIPs. This described both small and large molecule templates in two different 85 sections. Examples of biomacromolecules that have been imprinted include 86 lysozyme, bovine haemoglobin, human haemoglobin, amylase and bovine serum 87 albumin (BSA) as...

Exploring the peptide retention mechanism in molecularly imprinted polymers

“…These applications have just risen from the recent development of imprinting strategies due to the complexity of imprinting macromolecules. This has to take in account many different interactions, simultaneously occurring around the template molecule, and the template insolubility into organic solvents generally used for the polymeric synthesis [26][27] . However, several MIPs have been developed for peptide enrichment and employed in the sample preparation of proteomic workflows [28][29][30][31][32][33][34][35] .…”

Combined Layer/Particle Approaches in Surface Molecular Imprinting of Proteins: Signal Enhancement and Competition

“…A species/biomacromolecule usually contains several epitopes to which (different) antibodies can bind. In a future step it will be necessary to assess selectivity of the approach toward other proteins for this system, although recent BSA MIP have reported excellent selectivity [ 28 , 29 , 30 ]. Furthermore, previous experience with chemically related MIP matrices shows that they are much more rugged than biospecies.…”

Molecularly Imprinted Polymers as Extracting Media for the Chromatographic Determination of Antibiotics in Milk

“…MIPs have already been reviewed as sorbents in sample preparation techniques [ 9 , 10 , 11 ] such as solid-phase extraction (SPE) [ 12 , 13 , 14 ], solid-phase microextraction (SPME) [ 15 , 16 ] and on-line extraction techniques [ 17 ] for bioanalysis [ 18 ], pharmaceutical [ 19 ], environmental [ 20 ], food [ 21 ], and forensic analysis [ 22 ]. MIPs have also been reviewed for the extraction of non-steroidal anti-inflammatory drugs and analgesics [ 23 ], drugs of abuse [ 24 ], personal care products [ 25 ] and proteins [ 26 ]. Apart from sample preparation purposes, MIPs have already been reviewed as monolithic columns in high-performance liquid chromatography (HPLC) and capillary electrophoresis (CE) [ 27 , 28 ], in biosensors [ 29 ] and gas sensors [ 30 ], in drug delivery [ 31 ], for diagnostic purposes [ 32 , 33 ], in wastewater treatment [ 34 ] and for biomolecule identification and separation [ 35 ].…”