227 research outputs found
Selection of imprinted nanoparticles by affinity chromatography
Soluble molecularly imprinted nanoparticles were synthesised via iniferter
initiated polymerisation and separated by size via gel permeation
chromatography. Subsequent fractionation of these particles by affinity
chromatography allowed the separation of high affinity fractions from the
mixture of nanoparticles. Fractions selected this way possess affinity similar
to that of natural antibodies (Kd 6.6 Ă 10â8) M and were also able to
discriminate between related functional analogues of the templ
The stabilisation of receptor structure in low cross-linked MIPs by an immobilised template
In molecularly imprinted polymers (MIPs) a high level of cross-linking is
usually important for preserving the receptor structure. We propose here an
alternative approach for stabilising binding sites, which involves the use of an
immobilised template. The idea is based on the assumption that an immobilised
template will ââholdââ polymeric chains and complementary functionalities
together, preventing the collapsing of the binding sites. To test this
postulate, a range of polymers was prepared using polymerisable (2,4-diamino-6-
(methacryloyloxy)ethyl-1,3,5-triazine) and non-polymerisable (or extractable)
(2,4-diamino-6-methyl-1,3,5-triazine) templates, methacrylic acid as functional
monomer and ethylene glycol dimethacrylate as cross-linker. The level of cross-
linking was varied from 12 to 80%. Polymerisations were performed in
acetonitrile using UV initiation. Binding properties of the synthesised
materials were characterised both by HPLC and equilibrium batch binding
experiments followed by HPLC-MS or UV-visible detection. The adsorption
isotherms of polymers were obtained and fitted to the Langmuir model to
calculate dissociation constant, Kd, and concentration of binding sites for each
material. The results strongly indicate that the presence of an immobilised
template improves the affinity of MIPs containing low percentages of cross-
linker. The low cross-linked MIPs synthesised with a polymerisable template also
retain a reasonable degree of selectivity. Low crosslinked MIPs with such
binding characteristics would be useful for the creation of new types of optical
and electrochemical sensors, where induced fit or the ââgate effectââ could be
used more effectively for generating and enhancin
Direct replacement of antibodies with molecularly imprinted polymer (MIP) nanoparticles in ELISAÂ - development of a novel assay for vancomycin
A simple and straightforward technique for coating microplate wells with molecularly imprinted polymer nanoparticles (nanoMIPs) to develop ELISA type assays is presented here for the first time. NanoMIPs were synthesized by a solid phase approach with immobilized vancomycin (template) and characterized using Biacore 3000, dynamic light scattering and electron microscopy. Immobilization, blocking and washing conditions were optimized in microplate format. The detection of vancomycin was achieved in competitive binding experiments with a HRP-vancomycin conjugate. The assay was capable of measuring vancomycin in buffer and in blood plasma within the range 0.001-70 nM with a detection limit of 0.0025 nM (2.5 pM). The sensitivity of the assay was three orders of magnitude better than a previously described ELISA based on antibodies. In these experiments nanoMIPs have shown high affinity and minimal interference from blood plasma components. Immobilized nanoMIPs were stored for 1 month at room temperature without any detrimental effects to their binding properties. The high affinity of nanoMIPs and the lack of a requirement for cold chain logistics make them an attractive alternative to traditional antibodies used in ELIS
What children know about the source of their knowledge without reporting it as the source
We argue that, amongst 3- to 5- year-olds, failure to report the source of knowledge recently acquired in answer to âHow do you knowâŠ?â is due to a specific failure to make a causal inference, in line with source monitoring theory but not fuzzy trace theory. In three Experiments, children (N = 37; 30; 59) identified a hidden toy by seeing, feeling, or by being told, having had two modes of access on each trial, one informative (e.g. seeing a toy identified by colour) and the other uninformative (e.g. being told the toyâs colour by the Experimenter who had only felt it). Children who answered the know question wrongly nevertheless reported accurately who saw and who felt the toy, and what the well-informed player had said. They also realised when
the Experimenterâs uninformative access implied their own knowledge was unreliable, suggesting precocious working understanding of knowledge sources
A scoping review on occupational science research in European contexts
Background
A survey showed European occupational scientists cover a broad range in occupational science (OS) research, however, no contemporary overviews of European OS research exists, and current research may provide valuable information for OS and occupational therapy.
Aim
The aim was to provide an overview of contemporary European OS research.
Materials and method
A scoping review was performed, including studies conducted in Europe and published in the British Journal of Occupational Therapy (BJOT), the Scandinavian Journal of Occupational Therapy (SJOT) or the Journal of Occupational Science (JOS) between 2015 and 2020. The journals were systematically searched, and quality assessment and thematic analysis were undertaken.
Results
Findings from 93 articles identified many studies from the Nordic countries. Most studies applied qualitative research methods. Theoretical concepts from OS were used in data generating and discussions. A wide range of demographics, and living conditions were explored. Recent articles took a reflexive stance on the positionality of the researcher/s.
Conclusions
This review highlights the diversity of OS research, suggesting a solid theoretical knowledge base within European OS research.
Significance
The results contribute to further development and maturation of the discipline of OS in Europe and internationally
Introducing MINA-The Molecularly Imprinted Nanoparticles Assay
A new ELISAâ (enzymeâlinked immunosorbent assay)âlike assay is demonstrated in which no elements of biological origin are used for molecular recognition or signaling. Composite imprinted nanoparticles that contain a catalytic core and which are synthesized by using a solidâphase approach can simultaneously act as recognition/signaling elements, and be used with minimal modifications to standard assay protocols. This assay provides a new route towards replacement of unstable biomolecules in immunoassays
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