title: A multi-source portable light emitting diode spectrofluorometer.
abstract: A portable luminescence spectrofluorometer weighing only 1.5 kg that uses multiple light emitting diodes (LEDs) as excitation sources was developed and evaluated. Excitation using a sequence of seven individual broad-band LED emission sources enabled the generation of excitation-emission spectra using a light weight (<1.5 kg) spectrometer. Limits of detection for rhodamine 6G, rhodamine B, and fluorescein were 2.9, 3.2, and 11.0 nM, respectively. Generation of excitation-emission matrices (EEMs) enabled the analysis of samples containing mixtures of rhodamine B and fluorescein. Buffered saline plant and animal feed extracts were also analyzed using this instrument. These samples included the woody plants Pistacia lentiscus (Evergreen pistache or Mastic) and Philyria latifolia, and the herbaceous species Medicago sativa (alfalfa), Trifolium spp. (clover), and a feed concentrate. Application of multi-way principal component analysis (MPCA) to the resulting three-dimensional data sets enabled discernment among these various diet constituents.
authors.affiliation: Box 30001 MSC 3C, Department of Chemistry and Biochemistry, New Mexico State University, Las Cruces, New Mexico 88003-0001, USA.
authors.forename: Safwan
authors.initials: S
authors.lastname: Obeidat
authors.forename: Baolong
authors.initials: B
authors.lastname: Bai
authors.forename: Gary D
authors.initials: GD
authors.lastname: Rayson
authors.forename: Dean M
authors.initials: DM
authors.lastname: Anderson
authors.forename: Adam D
authors.initials: AD
authors.lastname: Puscheck
authors.forename: Serge Y
authors.initials: SY
authors.lastname: Landau
authors.forename: Tzach
authors.initials: T
authors.lastname: Glasser
mesh_terms: D000821:Animal Feed / Q000032:analysis; D000818:Animals; D004867:Equipment Design; D008027:Light; D008029:Lighting / Q000295:instrumentation / Q000379:methods; D010936:Plant Extracts / Q000737:chemistry; D025341:Principal Component Analysis; D012235:Rhodamines / Q000032:analysis; D012256:Riboflavin / Q000032:analysis; D012666:Semiconductors; D013050:Spectrometry, Fluorescence / Q000295:instrumentation
chemical_list: D010936:Plant Extracts; D012235:Rhodamines; C026188:rhodamine 6G; D012256:Riboflavin