Microspots

Microspots are very small, localized regions on a surface or within a system, typically defined by dimensions in the micrometer range. The term is used across multiple disciplines to describe tiny spots produced by focused energy, deposition methods, or imaging techniques. There is no single universal standard for a microspot size; instead, the size is determined by the specific equipment and purpose, with common diameters ranging from about 10 to several hundred micrometers (µm).

In microscopy and imaging, microspots can serve as calibration markers or localized sources of signal. They may represent small illuminated regions, fluorescence targets, or test points used to assess resolution, point-spread function, or photobleaching. In laser-based systems and confocal microscopes, microspots enable precise, localized measurements or demonstrations of optical performance.

In microfabrication and surface patterning, microspots are discrete deposition sites created by techniques such as inkjet printing, microcontact printing, or photolithography. These spots act as sensor elements, template features, or catalytic test sites. Typical spot sizes in these applications span from about 10 µm to a few hundred µm, with spacing and uniformity tailored to the task.

In biology and biotechnology, microspots underpin microarray technologies, where spots containing DNA, peptides, or proteins are printed on slides. Spot diameters commonly range from 25 to 150 µm, chosen to balance signal strength with high-density sampling and to minimize cross-talk between neighboring spots.

Practical considerations for working with microspots include controlling spot size uniformity, wettability of the substrate, alignment precision, and the potential for edge effects or material diffusion.