Polystyrene, derivatized

Using both elemental percentage nitrogen and adsorption studies with picric acid, maximum ion-exchange capacity has been calculated to be 2.7 mEq/g (37). This corresponds to exchange capacities typically observed for polymeric polystyrene-derivatized anion exchangers J04). 

The GBR resin works well for nonionic and certain ionic polymers such as various native and derivatized starches, including sodium carboxymethylcel-lulose, methylcellulose, dextrans, carrageenans, hydroxypropyl methylcellu-lose, cellulose sulfate, and pullulans. GBR columns can be used in virtually any solvent or mixture of solvents from hexane to 1 M NaOH as long as they are miscible. Using sulfonated PDVB gels, mixtures of methanol and 0.1 M Na acetate will run many polar ionic-type polymers such as poly-2-acrylamido-2-methyl-l-propanesulfonic acid, polystyrene sulfonic acids, and poly aniline/ polystyrene sulfonic acid. Sulfonated columns can also be used with water glacial acetic acid mixtures, typically 90/10 (v/v). Polyacrylic acids run well on sulfonated gels in 0.2 M NaAc, pH 7.75. 

Iodobeads (Thermo Fisher) is an immobilized preparation of a chloramine-T analog, consisting of nonporous, polystyrene beads of diameter 1/8" that have been derivatized to contain N-chlorobenzenesulfonamide groups (as the sodium salt) (refer to US patents 4,448,764 and 4,436,718). During the manufacturing process, the hydrophobic nature of the polystyrene is changed to a rather hydrophilic surface due to the chlorosulfonamide modifications. The surface... 

The microspheres—synthesised via a two-step process (acid-catalysed hydrolysis and condensation of 3-mercaptopropyltrimethoxysilane (MPS) in aqueous solution, followed by condensation catalysed by triethanolamine)—have a narrow size distribution (Figure 5.16) and are considerably more stable than polystyrene divinylbenzene microspheres as shown in phosphoramidite oligonucleotide synthesis by the excellent retention of fluorescence intensity in each of the reagent steps involved in phosphoramidite DNA synthesis (Figure 5.17, in which the organo-silica microsphere free thiol groups are derivatized with ATTO 550 maleimide coupled to the entrapped dye). 

Briefly, norbornene-derivatized silica was first reacted with Mo(N-2,6-i-Pr2-C6H3)(CHCMe2Ph)(OCMe(CF3)2)2, followed by (4 -(norbom-2-en-5-ylmethylen-oxy)terpyridine). Loading with Cu (I) afforded the desired ATRP support [18, 22-24], Typical metal loadings were in the range of 15 mmolg. Polystyrene (PS) obtained with these supports under ATRP-conditions showed comparably low poly-dispersities (PDI = 1.55-1.77). The ATRP system consisted of a metal center with one terpyridyl and presumably three acetonitrile ligands, which were at least in part substituted by monomer. Consequently, in contrast to standard systems [25], the equilibrium in this type of reaction did not require conformational... 

Sulfonated 8 and biotinylated polymer 38-coated streptavidin-derivatized polystyrene microspheres were useful as a platform for the detection of DNA... 

The surfaces included PLL, polystyrene, epoxy-terminated polyethylene glycol (PEG) or dendrimer slides, various amine-derivatized surfaces, and nitrocellulose-coafed slides. All proteins were printed in PBS, rinsed in TBS, and then blocked in 3% nonfat dry milk powder dissolved in TBS-0.1% Tween-20. A final rinse in TBS was performed prior to incubation. While no attempt was made to optimize print buffer or blocking conditions for each of the selected surfaces, if was apparenf fhaf wifh fhe exception of activated polystyrene, most chemistries performed af abouf fhe same levels, i.e., within two- to threefold af saturation. 

Fig. 6 Transmission electron micrograph (TEM) of the cross-section of a PDMAAm(poly-dimethylacrylamide)-b-PST(polystyrene) block-graft-copolymerized surface stained in iodine vapor, a Spurr s resin, b PST layer, c PDMAm layer, d dithiocarbamate (DC)-derivatized PST film...

Polystyrene does not enable the covalent, reversible attachment of synthetic intermediates unless the support is derivatized with suitable functional groups. The most common groups for the reversible attachment of intermediates are chloromethyl and hydroxymethyl, whereas aminomethyl groups are mainly used as non-cleavable points of attachment for linkers (see Chapter 3). 

Metallated polystyrenes are versatile intermediates for the preparation of a number of polystyrene derivatives. Metallated polystyrene has been prepared from haloge-nated polystyrenes by halogen-metal exchange [41,42,65,66] and by direct metallation of polystyrene [67-69] (see Chapter 4). Electrophiles suitable for the derivatization of metallated polystyrene include carbon dioxide, carbonyl compounds, sulfur, trimethyl borate, isocyanates, chlorosilanes, alkyl bromides, chlorodiphenylphosphine, DMF, oxirane, selenium [70], dimethyldiselenide [71], organotin halides [69], oxygen [72], etc. [41,42,65-67],... 

Polystyrene-bound 2-bromothiophene can be metallated by treatment with Grignard reagents. The resulting thienylmagnesium compounds can be directly treated with carbon electrophiles to yield the corresponding derivatized thiophenes. For some types of electrophile, transmetallation with CuCN might be required in order to obtain clean products (Entry 6, Table 15.10). 

The peptide is synthesized on a derivatized solid support, often a polyamide or polystyrene resin, and synthesis proceeds from C-terminus to N-terminus. The linker group, which provides the link between the resin and the peptide... 

An alternative solution is to produce a solid-phase particle that yields micromolar amount of product. Mimotopes Pty. Ltd. has developed and commercialized the SynPhase Crown and later Lanterns, a rigid polypropylene mold with a grafted layer of polystyrene. The solid-phase synthesis takes place on the derivatized graft.11... 

Reductive Animation for Synthesis of PAL-Resin-Bound Amines (59) (Fig. 10)15. To a suspension of 4-formyl-3,5-dimethoxyphennoxymethyl functionalized polystyrene resin (PAL)25 (10.0 g, 11.3 mmol) in DMF (350 ml) a primary amine (56.5 mmol) is added followed by addition of sodium triacetoxyborohydride (7.18 g, 33.9 mmol) and acetic acid (6.52 ml, 113 mmol). The suspension is shaken gently at RT overnight. Resin 59 is washed with methanol (4 x 300 ml) and CH2C12 (4 x 300 ml) and dried under vacuum. Subsequent derivatization products can be cleaved from the resin by a 2 h treatment with CH2Cl2/TFA/Me2S/H20 45 45 5 5. 

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