Epitope Mapping (also called antibody epitope mapping) is the set of experimental and computational approaches used to identify the precise antigen features an antibody recognizes and binds—down to specific amino acids, structural patches, or even interaction “hot spots.” In immunology terms, the epitope is the binding site on the antigen, while the antibody’s complementary binding surface is the paratope. Knowing exactly where binding occurs is foundational for understanding immune recognition, improving biologics, and designing better diagnostics and vaccines. Why Epitope Mapping Matters (Beyond “It Binds”) Antibodies can bind the same antigen in very different ways. Two antibodies may both “hit” the same protein yet differ dramatically in neutralization strength, cross-reactivity, or tolerance to mutations. Epitope mapping turns binding into actionable knowledge, helping teams: Differentiate antibodies that otherwise look similar by affinity alone (e.g., classifying binding regions and overlap patterns). Explain potency and mechanism of action, especially when blocking a receptor site or preventing conformational changes. Reduce off-target risk by detecting binding to conserved motifs shared across proteins. Guide design decisions for vaccines and diagnostics by focusing on minimal, protective, or assay-relevant epitopes. Two Big Epitope Types: Linear vs Conformational A key concept for practical…
SPOT Synthesis (often written as SPOT peptide synthesis or SPOT synthesis technique) is a positionally addressable, parallel solid-phase peptide synthesis method where many peptides are built simultaneously as discrete “spots” on a derivatized cellulose membrane. Instead of synthesizing one peptide at a time on resin beads, SPOT Synthesis dispenses activated amino acid solutions onto predefined membrane coordinates, enabling rapid generation of peptide libraries and arrays for downstream screening.  ⸻ What Makes SPOT Synthesis Unique? 1) Parallel synthesis on a planar cellulose support In SPOT Synthesis, the membrane acts as a flat solid support. Each printed droplet is absorbed into the porous cellulose and behaves like a tiny reaction “micro-compartment,” allowing hundreds to thousands of peptides to be synthesized in parallel on one sheet.  2) Addressable peptide libraries (arrays you can map by position) Every spot corresponds to a known sequence (or sequence mixture), which makes SPOT arrays especially useful when you need systematic coverage—such as scanning a protein sequence with overlapping peptides or exploring sequence–activity relationships.  3) Scale and throughput The method is widely described as supporting very high spot counts (from hundreds up to many thousands, depending on format and spot size). This density makes it…
