{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,12,13]],"date-time":"2025-12-13T05:17:39Z","timestamp":1765603059765,"version":"3.48.0"},"reference-count":75,"publisher":"MDPI AG","issue":"12","license":[{"start":{"date-parts":[[2025,12,11]],"date-time":"2025-12-11T00:00:00Z","timestamp":1765411200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100000780","name":"European Commission","doi-asserted-by":"publisher","award":["101060941"],"award-info":[{"award-number":["101060941"]}],"id":[{"id":"10.13039\/501100000780","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Daniel Greenberg, Susan Steinhauser, and The Greenberg Foundation","award":["NA"],"award-info":[{"award-number":["NA"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Gels"],"abstract":"<jats:p>LACMA\u2019s 19th-century Tibetan Altar Table with Auspicious Symbols is characterized by a complex stratigraphy comprising animal glue-based ground and paint layers, a presumably original tung oil-based varnish, and a dark surface layer composed of a complex mixture of paraffinic wax, shellac, and rapeseed oil, which obscures the object\u2019s original decorative scheme. This study examines the use of nanostructured fluids and organic solvents confined within hydrogels and organogels for the selective removal of the dark surface layer while preserving the underlying paint and varnish. Following the analysis of the artwork\u2019s constituent materials, cleaning tests were conducted and evaluated using visible and ultraviolet fluorescence (UVF) imaging, spectrophotometry, and digital microscopy. The homogeneous absorption of solvent mixtures by the organogels was assessed through gas chromatography\u2013mass spectrometry (GC\u2013MS). Results indicate that confining cleaning fluids within the gels\u2019 porous networks significantly improved solvent retention and control of fluid release. While conventional cleaning methods proved insufficiently selective, the gradual release of a nanostructured fluid containing a small amount of benzyl alcohol, combined with the nanostructural properties of the poly(vinyl alcohol)\u2013sebacic acid (PSA2) hydrogel, enabled targeted removal of the surface layer while preserving the integrity of the underlying layers.<\/jats:p>","DOI":"10.3390\/gels11121001","type":"journal-article","created":{"date-parts":[[2025,12,11]],"date-time":"2025-12-11T17:13:34Z","timestamp":1765473214000},"page":"1001","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Confined Fluids in Gel Matrices for the Selective Cleaning of a Tibetan Altar Table"],"prefix":"10.3390","volume":"11","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-4522-4142","authenticated-orcid":false,"given":"Chiara","family":"Biribicchi","sequence":"first","affiliation":[{"name":"Conservation Center, Los Angeles County Museum of Art, 5905 Wilshire Blvd, Los Angeles, CA 90036, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0009-0003-1515-5929","authenticated-orcid":false,"given":"Jessica","family":"Chasen","sequence":"additional","affiliation":[{"name":"Conservation Center, Los Angeles County Museum of Art, 5905 Wilshire Blvd, Los Angeles, CA 90036, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7373-445X","authenticated-orcid":false,"given":"Laura","family":"Maccarelli","sequence":"additional","affiliation":[{"name":"Conservation Center, Los Angeles County Museum of Art, 5905 Wilshire Blvd, Los Angeles, CA 90036, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2025,12,11]]},"reference":[{"key":"ref_1","unstructured":"Los Angeles County Museum of Art (2025, August 09). 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