Advances in chitosan-based adsorbents for sustainable and miniaturized analytical methods: a review.

The growing demand for sustainable analytical strategies has stimulated the study of new renewable materials for sample preparation. Chitosan, a low-toxicity, biodegradable, and low-cost biopolymer obtained from chitin, has emerged as a promising alternative for the adsorption and pre-concentration of organic and inorganic analytes. Its functional groups allow for various chemical modifications, enhancing selectivity and stability in acidic media. This review presents advances in chitosan-based adsorbents used in analytical methods from 2000 to 2026, emphasizing their performance in the extraction, pre-concentration, and matrix purification steps in spectrometric and chromatographic determinations. Key analytical parameters, including detection limits, precision, and recovery, are comparatively discussed to highlight progress, current challenges, and perspectives for the development of highly efficient and environmentally friendly analytical methods.