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Updated: Jan 22, 2026

Dissection of Midgut and Salivary Glands from Ae. aegypti Mosquitoes
Published on: July 4, 2007
Characterization of scallop midgut gland certified reference material for quantification of diarrhetic shellfish
Takashi Yarita1, Shinsuke Inagaki2, Ayano Miyamoto2
1National Metrology Institute of Japan, National Institute of Advanced Industrial Science and Technology, AIST Tsukuba Central 3, 1-1-1 Umezono, Tsukuba, Ibaraki 305-8563, Japan; College of Agriculture, Ibaraki University, 3-21-1 Chuuo, Ami, Inashiki, Ibaraki 300-0393, Japan.
Abstract:
A scallop midgut gland certified reference material, NMIJ CRM 7520-a, was developed for validation and quality assurance during the inspection of shellfish for diarrhetic shellfish toxins. The candidate material was prepared by using naturally-toxic and nontoxic boiled midgut glands spiked with okadaic acid (OA). The homogeneity and stability of the material were found to be appropriate. For the characterization of OA and dinophysistoxin-1 (DTX1), nine participants were involved in a co-laboratory study based on the Japanese Official Testing Method, where the compounds were assayed by liquid chromatography-tandem mass spectrometry following alkaline hydrolysis. The analytical values were obtained by the standard addition method with a standard spiking solution calibrated using the standard-solution certified reference materials OA and DTX1. The certified concentrations with expanded uncertainties (coverage factor k = 2, approximate 95% confidence interval) were determined to be (0.205 ± 0.061) mg/kg for OA and (0.45 ± 0.11) mg/kg for DTX1.
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