A280

A280 is a designation used in several distinct domains. In transportation, A280 is used as a route number for major roads in various countries; the actual path and jurisdiction vary across regions, and the designation typically identifies an arterial connector or feeder route.

In science, A280 refers to absorbance at 280 nanometers, a standard measurement in spectrophotometry for assessing protein concentration and nucleic acid purity. The A260/A280 ratio is commonly used as a criterion for purity; a ratio of about 1.8–2.0 suggests relatively pure DNA or RNA, while lower values indicate protein contamination. Absorbance at 280 nm arises mainly from aromatic amino acids such as tryptophan and tyrosine.

In industry and product catalogs, A280 can be a model or part number used by manufacturers to identify components or equipment. The same label may appear across different product lines or companies, sometimes representing unrelated items.

Because A280 spans multiple domains, context is essential to determine which meaning applies. If encountered in scientific data, it most likely refers to spectrophotometry; in infrastructure planning or travel literature, it may denote a road; in catalogs, it could indicate a specific model or part.