title: Microfluidic biosensor for β-Hydroxybutyrate (βHBA) determination of subclinical ketosis diagnosis.
abstract: BACKGROUND
  Determination of β-hydroxybutyrate (βHBA) is a gold standard for diagnosis of Subclinical Ketosis (SCK), a common disease in dairy cows that causes significant economic loss. Early detection of SCK can help reduce the risk of the disease progressing into clinical stage, thus minimizing economic losses on dairy cattle. Conventional laboratory methods are time consuming and labor-intensive, requiring expensive and bulky equipment. Development of portable and robust devices for rapid on-site SCK diagnosis is an effective way to prevent and control ketosis and can significantly aid in the management of dairy animal health. Microfluidic technology provides a rapid, cost-effective way to develop handheld devices for on-farm detection of sub-clinical ketosis. In this study, a highly sensitive microfluidics-based biosensor for on-site SCK diagnosis has been developed.
  
  
  RESULTS
  A rapid, low-cost microfluidic biosensor with high sensitivity and specificity was developed for SCK diagnosis. Determination of βHBA was employed as the indicator in the diagnosis of SCK. On-chip detection using miniaturized and cost-effective optical sensor can be finished in 1 minute with a detection limit of 0.05 mM concentration. Developed microfluidic biosensor was successfully tested with the serum samples from dairy cows affected by SCK. The results of the developed biosensor agreed well with two other laboratory methods. The biosensor was characterized by high sensitivity and specificity towards βHBA with a detection limit of 0.05 mM.
  
  
  CONCLUSIONS
  The developed microfluidic biosensor provides a promising prototype for a cost-effective handheld meter for on-site SCK diagnosis. By using microfluidic method, the detection time is significantly decreased compared to other laboratory methods. Here, we demonstrate a field-deployable device to precisely identify and measure subclinical ketosis by specific labeling and quantification of β-hydroxybutyate in cow blood samples. A real-time on-site detection system will maximize convenience for the farmers.
authors.affiliation: BioNano Laboratory, School of Engineering, University of Guelph, Guelph, ON, N1G 2W1, Canada. xuanw@uoguelph.ca.
authors.forename: Xuan
authors.initials: X
authors.lastname: Weng
authors.affiliation: Department of Industrial Engineering, South China University of Technology, Guangzhou, Guangdong, 510640, China. wenting.chau@gmail.com.
authors.forename: Wenting
authors.initials: W
authors.lastname: Zhao
authors.affiliation: BioNano Laboratory, School of Engineering, University of Guelph, Guelph, ON, N1G 2W1, Canada. sneethir@uoguelph.ca.
authors.forename: Suresh
authors.initials: S
authors.lastname: Neethirajan
authors.affiliation: Department of Population Medicine, Ontario Veterinary College, University of Guelph, Guelph, ON, N1G 2W1, Canada. tduffiel@uoguelph.ca.
authors.forename: Todd
authors.initials: T
authors.lastname: Duffield
mesh_terms: D020155:3-Hydroxybutyric Acid / Q000032:analysis / Q000097:blood*; D000818:Animals; D015374:Biosensing Techniques / Q000379:methods*; D002417:Cattle; D002418:Cattle Diseases / Q000175:diagnosis*; D004867:Equipment Design; D005260:Female; D007662:Ketosis / Q000175:diagnosis / Q000662:veterinary*; D056656:Lab-On-A-Chip Devices; D057230:Limit of Detection; D044085:Microfluidics / Q000191:economics / Q000295:instrumentation / Q000379:methods*; D012680:Sensitivity and Specificity
chemical_list: D020155:3-Hydroxybutyric Acid