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Imprinted bead production methods

1 Utilising the pores in preformed beads (method 1 in Table 12.1) [Pg.307]

Cross-linked beads made by vinylic polymerisations usually have some residual polymerisable functionalities [8], which allows the secondary imprinting polymerisation to covalently attach to the bead structure giving very stable particles. Where glass or silica is used a pretreatment with vinyl [9] or methacryloxy [2] silane derivatives ensures stable covalent attachment, while at the same time blocking surface silanol groups which might otherwise interfere with imprinting. [Pg.307]

In a typical procedure, the beads are mixed with an imprinting mixture (containing somewhat more solvent than usual) and mixed for some time with application of mild vacuum and/or sonication to ensure penetration of the mixture into the pore structure. The slurry is then heated to initiate polymerisation. After completion the beads are extensively washed and treated as for ground particles. [Pg.307]

Bulk — in bead pores (may fill the pores or just coat the surfaces of the pores) [Pg.308]

Random aggregates or precipitates (could be monodisperse beads if stabilisers are present) [Pg.309]


When considering the suitability of a bead production technique for imprinting, it is essential to evaluate the compatibility of the conditions used for polymerisation with those required for complex formation between functional monomers and templates. Where covalent imprinting methods are used, the covalent adducts are often highly stable and need quite harsh conditions to disrupt them. Such adducts could be used in most of the procedures described below with reasonable expectation of success. The same can be said for many metal-chelate complexes, which have stabilities approaching covalently bonded structures. The use of cyclic boronate esters is an exception. This adduct is unstable in water and hence cannot be combined efficiently with aqueous suspension polymerisation. [Pg.306]

In summary, no perfect and universally applicable solution to making beaded imprinted polymers has yet been invented, but a number of promising techniques have been introduced during the last few years which will doubtless be further developed and refined alongside a range of novel approaches. Only time will tell whether any of these techniques will displace crushed bulk polymer as the production method of choice, either in the laboratory or on a production scale. [Pg.322]

Liquid fluorocarbon was used as continuous phase by Perez-Moral and Mayes [19] as well. They proposed a new method for rapid synthesis of MIP beads, in that they prepared 36 polymers imprinted for propranolol and morphine with different amounts of EDMA as a cross-linker and different functional monomers (MAA, acrylic acid, hydroxyethyl methacrylate, 4-vinylpyridine) directly in SPE cartridges. The properties of MIP microspheres prepared by this method were very similar in terms of size, morphology and extent of rebinding to microspheres prepared by conventional suspension polymerisation in perfluorocarbons as well as to bulk polymers prepared in the same solvent. The most notable advantages of this method are no waste production (no transfer of beads during washing steps) and possible direct use for a variety of screening, evaluation and optimisation experiments. [Pg.34]

Figure 9 Common preparation methods for making molecularly imprinted polymer beads and the size range of the product beads. A general comment (+ pro con) on the different methods is included. Figure 9 Common preparation methods for making molecularly imprinted polymer beads and the size range of the product beads. A general comment (+ pro con) on the different methods is included.

See other pages where Imprinted bead production methods is mentioned: [Pg.307]    [Pg.307]    [Pg.315]    [Pg.311]    [Pg.305]    [Pg.435]   


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