When the coated probe, sorptive material, or small solvent phase contacts a target surface, chemical compounds partition from that surface into the extracting phase. The extracted material is then desorbed or transferred for instrumental measurement. This sequence concentrates surface-associated molecules before analysis, allowing a small sampled region to provide chemically informative material.
The probe or sorptive material provides the phase that receives compounds from the contacted surface. Its small format supports localized sampling while limiting the amount of sample and solvent required. After contact, the retained analytes can be desorbed or transferred to an instrument, linking the physical sampling step with chemical measurement.
Localized contact lets investigators examine chemical composition at a defined position rather than treating an entire specimen as uniform. In biological analysis, this supports spatially resolved measurements across tissues, cells, biomaterials, or laboratory surfaces. The approach can therefore retain positional information while using limited material from specimens that may be complex or difficult to replace.
A typical workflow begins by bringing a coated probe, sorptive material, or small solvent phase into contact with the selected surface. Compounds move into the extracting phase during contact. The collected material is then desorbed or transferred for instrumental measurement, producing an analytical record of chemical residues present at the sampled location.
In biology, Surface micro-extraction can be applied to tissues, cells, biomaterials, and laboratory surfaces. The collected compounds may include metabolites, lipids, drugs, and other molecular residues. This range makes the technique useful when researchers need chemical information from a particular biological or experimental surface rather than from a large, homogenized sample.
The method is especially useful when specimens are limited, complex, or require localized examination. Its low sample consumption can help preserve biological material, while direct surface sampling supports spatially resolved analysis. Researchers can consequently investigate molecular residues on specific regions of tissues, cells, biomaterials, or laboratory surfaces without requiring extensive sample preparation described in the source.