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Solid-phase microextraction (SPME) via on-fiber derivatization with O-(2,3,4,5,6-pentafluorobenzyl)-hydroxylamine (PFBHA) and gas chromatographic determination is considered a technique of choice in many analytical fields for formaldehyde (FA) monitoring. Vapor phase adsorption models of experimentally loaded PFBHA on porous divinylbenzene (DVB) SPME were investigated at 60°C, 35 cm s−1 of air velocity, in a 1-64 min range: with the fiber completely exposed, loaded PFBHA was about 276 μg. Among the models tested, i.e. heat transfer, pseudo-second-order (PSO), Elovich, intra-particle diffusion, extra-particle diffusion and Langmuir, PFBHA adsorption was best fit by the PSO model, showing agreement with experimental data (272 μg). The sampling rate of FA in our conditions, obtained with a permeation tube system, was in agreement with literature (17.4 and 18.3 mL min−1, respectively). Thus, an overall standardization of the sampling phase is presented, leaving the sampling time as the most crucial parameter to be set for future applications.

Formaldehyde (FA) is a carbonyl compound, ubiquitous in the environment and among the most widespread pollutants: it has exhibited toxic properties and is classified as a human carcinogen. FA is released from several sources, both temporary (e.g., combustion processes) and permanent (e.g., building products). This work proposes an innovative fully-automated application of headspace solid-phase microextraction (SPME) with on-fiber derivatization for the analysis of airborne FA emitted from liquid solutions or solid manufacts, in static mode, via gas chromatography-mass spectrometry. The method was tested in a wide range of airborne FA concentrations, using SPME and SPME Arrow fibers: the inter-day LOD and LOQ for SPME and SPME Arrow were evaluated, resulting in 0.072 and 0.215 ppm and 0.014 and 0.042 ppm, respectively. Moreover, other conventional detectors, such as Electron Capture Detector (ECD), Thermoionic Specific Detector (TSD), Photoionization Detector (PID), and Flame Ionization Detector (FID), were tested to set an analytical method to meet different requirements. The sensitivity and linearity of PID, FID and MS were comparable, while TSD and ECD were not suitable for the developed method, due to issues of response or linearity. MS results to be the most suitable and perfoming detector, however PID and FID result to be cheaper valid alternatives.