Peptide screening, dose-response analyses and spatial immobilization of targeted particles onto intact matrices. Using the methods described in the text, individual phage were tested for either their ability to bind to immobilized components (for example, chondroitin sulfate, collagen 4, bovine serum albumin or to sonicated matrix samples, as illustrated by (A) binding of IT8 peptides to immobilized chondroitin sulfate or (B) dose-response analyses to specific peptides binding to sonicated matrix samples immobilized in ELISA wells. Spatial binding to matrix sections was established by placing targeted particles as (C) continuous lines along two sides (sample 2) or as a dot (sample 3). Phosphate-buffered saline alone was negative (sample 1). In all instances, binding of particles was assessed by chemiluminescence.