The present invention is a patch-sized apparatus for use with an apparel to detect seminal fluid that includes disposable housing. The disposable housing is removably attached to the apparel. The disposable portion incorporates therein a fluid channel comprising a chemical solution to detect seminal fluid present on the surface of the apparel. The chemical solution includes but not limited to 1-Naphthylphosphate (disodium salt); and prostate-specific antigen (PSA)(A67-B/E3).

Porous sol-gel material essentially consisting of units of one or more first polyalkoxysilanes chosen from the following compounds: (chloromethyl)triethoxysilane; 1,3-dimethyltetramethoxydisiloxane; ethyltrimethoxysilane; triethoxy(ethyl)silane; triethoxymethylsilane; triethoxy(vinyl)silane; trimethoxymethylsilane; trimethoxy(vinyl)silane; tetraethoxysilane or tetramethoxysilane (TMOS) and of units of one or more second polyalkoxysilanes chosen from the following compounds: (N-(3-(trimethoxysilyl)propyl)ethylenediamine; 3-aminopropyltriethoxysilane (APTES) and 3-aminopropyltrimethoxysilane, in a first polyalkoxysilane/second polyalkoxysilane molar ratio of 1/0.01 to 1/1, optionally comprising a probe molecule, method of preparation and applications in the trapping of monocyclic aromatic hydrocarbons and other pollutants or in their detection.