title: Facile colorimetric method for simple and rapid detection of endotoxin based on counterion-mediated gold nanorods aggregation.
abstract: Existence of endotoxin in food and injection products indicates bacterial contaminations and therefore poses threat to human health. Herein, a simple and rapid colorimetric method for the effective detection of endotoxin in food and injections based on counterion-mediated gold nanorods aggregation is first proposed. By taking advantage of the color change of unmodified gold nanorods resulted from endotoxin mediated gold nanorods aggregation, endotoxin could be detected in the concentration range of 0.01-0.6 μM. Further, we studied the performance of gold nanorods with different aspect ratios (2.7 and 3.3) in determination of endotoxin and found that gold nanorods with higher aspect ratio (AR) showed superiority in the sensing sensitivity of endotoxin. A good specificity for endotoxin, a detection limit of 0.0084 μM and recoveries ranging from 84% to 109% in spiked food and injection samples are obtained with the colorimetric method. Results demonstrate that the present method provides a novel and effective approach for on-site screening of endotoxin in common products, which is beneficial for monitoring and reducing the risk of bacterial contaminations in food and injections production.
authors.affiliation: College of Food Science and Engineering, Northwest A&F University, Yangling 712100, Shaanxi, China.
authors.forename: Yashan
authors.initials: Y
authors.lastname: Wang
authors.affiliation: College of Food Science and Engineering, Northwest A&F University, Yangling 712100, Shaanxi, China.
authors.forename: Daohong
authors.initials: D
authors.lastname: Zhang
authors.affiliation: College of Food Science and Engineering, Northwest A&F University, Yangling 712100, Shaanxi, China.
authors.forename: Wei
authors.initials: W
authors.lastname: Liu
authors.affiliation: College of Food Science and Engineering, Northwest A&F University, Yangling 712100, Shaanxi, China.
authors.forename: Xiao
authors.initials: X
authors.lastname: Zhang
authors.affiliation: College of Food Science and Engineering, Northwest A&F University, Yangling 712100, Shaanxi, China.
authors.forename: Shaoxuan
authors.initials: S
authors.lastname: Yu
authors.affiliation: College of Food Science and Engineering, Northwest A&F University, Yangling 712100, Shaanxi, China.
authors.forename: Tao
authors.initials: T
authors.lastname: Liu
authors.affiliation: College of Food Science and Engineering, Northwest A&F University, Yangling 712100, Shaanxi, China.
authors.forename: Wentao
authors.initials: W
authors.lastname: Zhang
authors.affiliation: College of Food Science and Engineering, Northwest A&F University, Yangling 712100, Shaanxi, China.
authors.forename: Wenxin
authors.initials: W
authors.lastname: Zhu
authors.affiliation: College of Food Science and Engineering, Northwest A&F University, Yangling 712100, Shaanxi, China. Electronic address: wanglong79@yahoo.com.
authors.forename: Jianlong
authors.initials: J
authors.lastname: Wang
mesh_terms: D003102:Colloids / Q000737:chemistry; D003124:Colorimetry / Q000295:instrumentation*; D004731:Endotoxins / Q000032:analysis*; D005504:Food Analysis / Q000379:methods*; D005506:Food Contamination / Q000032:analysis*; D006046:Gold / Q000737:chemistry*; D007477:Ions; D043942:Nanotubes / Q000737:chemistry* / Q000648:ultrastructure*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
chemical_list: D003102:Colloids; D004731:Endotoxins; D007477:Ions; D006046:Gold
keywords: Colorimetric detection; Endotoxin; Gold nanorods