Affinity ladders

The results of these measurements are affinity ladders, in which a qualitative trend of binding affinities can be observed. Because of the temperature problem these values are only relative data and conversion into absolute data is not easily possible. 

Meot-Ner Mautner M, Sieck LW (1991) Proton affinity ladders from variable-teanptuature equilibrium measurements. 1. A reevaluation of the upper proton affinity range. J Am Chem Soc 113 4448-4460... 

We have used gel retardation assays to study proteins binding to the ARE. We used a probe consisting of the 42 base ARE. When the probe was multimerised in four or six tandem copies, protein, AREF (ARE Factor) from nuclear extracts of anaerobically induced suspension cultures was bound to the probe and showed a ladder of retarded bands (Fig. 2). This ladder of bands was completed specifically by the 4x ARE probe but not by a probe containing four copies of the octopine synthase enhancer element or pUC DNA even in 100-fold excess. Probes which contained one or two copies of the ARE did not show any binding. The need to multimerise the probe presumably results either from low affinity of the protein for the DNA or low abundance of AREF in nuclear extracts. 

Fluoroalkyl-substituted naphtalenetetracarboxyUc diimide can be processed into thin films from fluorinated solvents to yield mobilities of 0.01 cmWs (bottom gate FET with Si02 dielectric, and gold contacts) [57]. The ladder polymer poly(benzobi-simidazobenzophenanthroline) (BBL) has an electron affinity of 4.0-4.4 eV and can be solution processed into microcrystaUine thin films from Lewis and methanesulfonic... 

In the ladder model treatment of Blizard, an alternative termination of the line of springs (Fig. 10-3) was considered in which each end, rather than being fixed, is attached to three other such lines, each of these to three more, and so on indefinitely, thus reproducing the connectivity of a tetrafunctional network. This.proyision increases the equilibrium compliance by a factor of 2 (corresponding-fo the factor of (/ — 2)//mentioned in Section I above), and it modifies the frequency dependence, which is now expressed by a rather complicated combination of hyperbolic functions. This frequency dependence of J" is also shown in Fig. 10-7 the maximum is slightly broader than for fixed cross-links (i.e., cross-links with affine deformation). 

This procedure is carried out for the desired number of cycles, and the final array of beads is screened for binding with a particular receptor. Beads that exhibit high-affinity binding can be isolated and reacted with CNBr to produce a set of ladder peptides ... 

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