title: Dried Saliva Spot (DSS) as a Convenient and Reliable Sampling for Bioanalysis: An Application for the Diagnosis of Diabetes Mellitus.
abstract: This paper proposes the dried saliva spot (DSS) as a convenient sampling technique for bioanalysis. The analytical method with the DSS was used for the determination of D,L-lactic acid (D,L-LA) and the D/L ratio of diabetic patients and prediabetic persons for the simple screening of the disease. The D,L-LA in the DSS was labeled with a chiral reagent (DMT-3(S)-Apy) for carboxylic acids and determined by UPLC-ESI-MS/MS. The limits of detection (signal-to-noise ratio (S/N) = 3) for the DSS analysis were on the amol level (∼30 amol). Because good stability, recovery, accuracy, and precision of the D,L-LA for the DSS method was also obtained from the proposed procedure, the DSS method was applied to the determination of the D- and L-isomers of LA of diabetic patients, and prediabetic and healthy persons. The D/L-LA ratio by the present DSS method and the HbA1c value in blood were well-correlated to the serious diabetic patients, whereas the relation in the prediabetic persons was not very good. The reason seems to be due to the rough saliva sampling, and not to the DSS method, because strict regulation was not requested for the prediabetic and healthy persons. In order to have a successful DSS analysis, the stability of the target molecule, the detection sensitivity to the target molecule, and the validated determination method are important.
authors.affiliation: Laboratory of Analytical and Bio-Analytical Chemistry, School of Pharmaceutical Sciences, University of Shizuoka , 52-1 Yada, Suruga-ku, Shizuoka 422-8526, Japan.
authors.forename: Masahiro
authors.initials: M
authors.lastname: Numako
authors.affiliation: Laboratory of Analytical and Bio-Analytical Chemistry, School of Pharmaceutical Sciences, University of Shizuoka , 52-1 Yada, Suruga-ku, Shizuoka 422-8526, Japan.
authors.forename: Takahiro
authors.initials: T
authors.lastname: Takayama
authors.affiliation: Department of Pharmaceuticals, Numazu City Hospital , Harunoki, Higashi-Shiizi, Numazu 410-0302, Japan.
authors.forename: Ichiro
authors.initials: I
authors.lastname: Noge
authors.affiliation: Department of Clinical and Molecular Endocrinology, Numazu City Hospital , Harunoki, Higashi-Shiizi, Numazu 401-0302, Japan.
authors.forename: Yutaka
authors.initials: Y
authors.lastname: Kitagawa
authors.affiliation: Laboratory of Analytical and Bio-Analytical Chemistry, School of Pharmaceutical Sciences, University of Shizuoka , 52-1 Yada, Suruga-ku, Shizuoka 422-8526, Japan.
authors.forename: Kenichiro
authors.initials: K
authors.lastname: Todoroki
authors.affiliation: Laboratory of Analytical and Bio-Analytical Chemistry, School of Pharmaceutical Sciences, University of Shizuoka , 52-1 Yada, Suruga-ku, Shizuoka 422-8526, Japan.
authors.forename: Hajime
authors.initials: H
authors.lastname: Mizuno
authors.affiliation: Laboratory of Analytical and Bio-Analytical Chemistry, School of Pharmaceutical Sciences, University of Shizuoka , 52-1 Yada, Suruga-ku, Shizuoka 422-8526, Japan.
authors.forename: Jun Zhe
authors.initials: JZ
authors.lastname: Min
authors.affiliation: Laboratory of Analytical and Bio-Analytical Chemistry, School of Pharmaceutical Sciences, University of Shizuoka , 52-1 Yada, Suruga-ku, Shizuoka 422-8526, Japan.
authors.forename: Toshimasa
authors.initials: T
authors.lastname: Toyo'oka
mesh_terms: D002851:Chromatography, High Pressure Liquid; D003890:Desiccation; D003920:Diabetes Mellitus / Q000175:diagnosis* / Q000378:metabolism*; D006442:Glycated Hemoglobin / Q000032:analysis; D006801:Humans; D019344:Lactic Acid / Q000032:analysis; D012463:Saliva / Q000737:chemistry*; D021241:Spectrometry, Mass, Electrospray Ionization; D053719:Tandem Mass Spectrometry
chemical_list: D006442:Glycated Hemoglobin; D019344:Lactic Acid; C517652:hemoglobin A1c protein, human