RESUMO
BACKGROUND: For monitoring biomarkers, saliva has several distinct advantages over other biological fluids. Saliva sampling is relatively non-invasive and enables the collection from either adults or infants under many different circumstances. However, there is no collection device that can be speedily used for analysis in the field. The aim of the present study was to evaluate the suitability of a new device, termed Muddler, compared with commercially available collection devices. METHODS: Saliva was collected from healthy volunteers. The collection devices such as Muddler, eye sponge, Salivette® Cotton (SC) and Salivette® Synthetic (SS) were evaluated in terms of the volume and/or composition of the collected saliva. The amounts of immunoglobulin A (IgA) and lactofferin in saliva were assessed by the enzyme-linked immunosorbent assays with the corresponding antibodies. Amylase activity was measured using a commercially available kit, and high molecular weight complexes including mucin were assessed by SDS-PAGE staining. RESULTS: A newly developed Muddler, which was made of plastic plate, was the best device for collecting a constant volume of saliva among all the devices examined in the present study. Furthermore, Muddler can collect without change in composition of salivary proteins such as IgA, lactoferrin, amylase, and mucin complex, whereas the levels of the salivary proteins obtained with all the commercial devices used were clearly different from those in original saliva. CONCLUSIONS: The newly developed Muddler was the best collection device in terms of the accuracy of collection and the reliability of measurements among all the devices examined in the present study.