Evaluation of saliva collection devices for the analysis of proteins

Background: Human saliva mirrors the body's health and can be collected non-invasively, does not require specialized skills and is suitable for large population based screening programs. The aims were twofold: to evaluate the suitability of commercially available saliva collection devices for quantifying proteins present in saliva and to provide levels for C-reactive protein (CRP), myoglobin, and immunoglobin E (IgE) in saliva of healthy individuals as a baseline for future studies.

Methods: Saliva was collected from healthy volunteers (n=17, ages 18-33years). The following collection methods were evaluated: drool; Salimetrics® Oral Swab (SOS); Salivette® Cotton and Synthetic (Sarstedt) and Greiner Bio-One Saliva Collection System (GBO SCS®). We used AlphaLISA® assays to measure CRP, IgE and myoglobin levels in human saliva.

Results: Significant (p<0.05) differences in the salivary flow rates were observed based on the method of collection, i.e. salivary flow rates were significantly lower (p<0.05) in unstimulated saliva (i.e. drool and SOS), when compared with mechanically stimulated methods (p<0.05) (Salivette® Cotton and Synthetic) and acid stimulated method (p<0.05) (SCS®). Saliva collected using SOS yielded significantly (p<0.05) lower concentrations of myoglobin and CRP, whilst, saliva collected using the Salivette® Cotton and Synthetic swab yielded significantly (p<0.05) lower myoglobin and IgE concentrations respectively.

Conclusions: The results demonstrated significantly relevant differences in analyte levels based on the collection method. Significant differences in the salivary flow rates were also observed depending on the saliva collection method. The data provide preliminary baseline values for salivary CRP, myoglobin, and IgE levels in healthy participants and based on the collection method.