Droplet digital PCR (ddPCR) method for the detection and quantification of goat and sheep derivatives in commercial meat products
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A highly precise, quantitative method based on the droplet digital polymerase chain reaction (ddPCR) technique was developed to identify and quantify the goat and sheep content in meat products. A formula for calculating raw meat weight based on DNA copy number was established. Exclusive specificity was verified using samples from 24 different animal species, and inclusive specificity between goat and sheep was tested using five different breeds for each species. The limit of detection and the limit of quantitation for both goat and sheep were 1 and 5 copies/μL, respectively, using a cloned plasmid containing goat- and sheep-specific target DNA fragments as calibrators. The accuracy and applicability of the method were verified using mixed powder samples with known proportions of goat and sheep meat, simulate meatball samples, and commercially available products, respectively. The results confirmed that the developed ddPCR methods are highly precise for identifying and quantifying the goat and sheep meat, indicating their potential applicability in future routine analyses.
KeywordsDroplet digital PCR Quantification Nuclear DNA Plasmid Meat product
The authors are grateful to the reviewers for their careful corrections of the manuscript.
Compliance with ethical standards
Financial support from the Shanghai Science and Technology Commission Standard Special Fund (16DZ0501501), Shanghai Entry-Exit Food and Feed Safety Special Technology Service Platform Fund (17DZ2293700), Project funded by China Postdoctoral Science Foundation (2017M611628), Huaian Technical Fund (HAS201618) and Shanghai Entry-Exit Inspection and Quarantine Bureau of Science and Technology Plan Projects Fund (HK008-2017) are acknowledged with thanks.
Conflict of interest
The authors declare that there is no conflict of interests regarding the publication of this paper.
Compliance with ethics requirements
This article does not contain any studies with human participants or animals performed by any of the authors.
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