Polystyrene streptavidin-coated

Wilson JN, Wang Y, Lavigne JJ, Bunz UHF. A biosensing model system selective interaction of biotinylated PPEs with streptavidin-coated polystyrene microspheres. Chem Commun 2003 1626-1627. 

Figure 8 Chemiluminescent (A and B) and bioluminescent (C) detections for immobilized hybridizations of PCR product. Dg, digoxigenin Bt, biotin Ad, avidin. Procedure A [30] Biotin moiety is incorporated into PCR products during the amplification reaction, using one 5 -biotinylated primer. The product is hybridized with a Dg-labeled probe and is immobilized on streptavidin-coated magnetic beads. This capture reaction is carried out for 30 min at 37°C. A permanent magnet is used to sediment the beads during washing to remove unbound DNA. By incubation with the washed beads for 45 min at 37°C, anti-Dg antibody conjugated to HRP enzyme is bound to the Dg-labeled probe, and luminol reaction is performed for CL detection. Procedure B [31] Wells of a polystyrene microtiter plate are activated with l-ethyl-3-(3-dimethylaminopropyl)-carbodiimide, and then coated with a labeled cDNA probe complementary to an internal region of the target DNA.

In one report, the optical tweezers were used to hold a bend in order to stretch a DNA molecule. First, a DNA molecule (XDNA) was biotin-congugated so that it could be attached to a streptavidin-coated polystyrene bead. The bead was held by optical tweezers inside a PDMS chip. The other end of the DNA was labeled with digoxigenin to be immobilized on the channel coated with anti-digoxigenin antibody. The DNA was stretched by moving the chip, with the bead being held by the optical tweezers [868]. 

Streptavidin-coated fluorescent polystyrene nanospheres [Huospheies (green fluores cence) and TransFluospheres (red fluorescence)] were used in single color flow cytometry to detect the EGFR on A431 cells (human epidermoid carcinoma cells) [53]. The results showed that the fluorescent nanospheres provided a... 

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

In protein microarrays, capture molecules need to be immobilized in a functional state on a solid support. In principle, the format of the assay system does not limit the choice of appropriate surface chemistry. The same immobilization procedure can be applied for both planar and bead-based systems. Proteins can be immobilized on various surfaces (Fig. 1) (12). Two-dimensional polystyrene, polylysine, aminosilane, or aldehyde, epoxy- or thiol group-coated surfaces can be used to immobilize proteins via noncovalent or covalent attachment (13,14). Three-dimensional supports like nitrocellulose or hydrogel-coated surfaces enable the immobilization of the proteins in a network structure. Larger quantities of proteins can be immobilized and kept in a functional state. Affinity binding reagents such as protein A, G, and L can be used to immobilize antibodies (15), streptavidin is used for biotinylated proteins (16), chelate for His-tagged proteins (17, 18), anti-GST antibodies for GST fusion proteins (19), and oligonucleotides for cDNA or mRNA-protein hybrids (20). 

Fig.26 Pseudo-color time-resolved image of polystyrene nanobeads containing Pt porphyrin and conjugated to streptavidin immobilized to a biotinylated microarray surface (black teflon coated 96-well glass slide, spot diameter 1 mm, Erie Scientific) in different concentrations (25, 15, 10, 5, Ong streptavidin per well) [167]...

An example of the immobilization on polystyrene beads is the bead-bed micro-ELISA system of Kitamori et al. [403]. The beads were coated with a capture antibody and loaded into the reaction channel of the ELISA microchip (Scheme 4.92a). Next, solutions containing antigen (Scheme 4.92b), a biotinylated secondary antibody (Scheme 4.92c) and a streptavidin-peroxidase conjugate were introduced into the channel (Scheme 4.92d). Finally, the substrate for peroxidase was continuously... 

Similar assays for measuring protease activity were also reported by Whitten and coworkers [49], These assays utilize polystyrene microspheres that are coated with streptavidin (a biotin-binding protein) and a biotinylated anionic fluorescent conjugated polyelectrolyte or a cationic polyelectrolyte, A biotinylated quencher-labeled peptide serves as a substrate for the enzyme and when mixed with the microspheres, a strong complex similar to the one in the DNA assays described in Section 13,3,1, through the biotin-avidin interaction is created [49], A schematic drawing of the assay is shown in Figure 13,7,... 

Lanthanide chelate-dyed polystyrene particles containing carboxylic acid groups have been covalently coated with antibodies, streptavidin [95], and nucleic acids [96] for different biomolecular-binding assays. Particulate labels can be coated with antibodies and used as such, but the obvious steric and kinetic problems associated with the large molecular size can be particularly avoided by indirect detection of the bound antibodies using, e.g., biotin-streptavidin interaction [97,... 

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