Label-free electrochemiluminescent biosensor for rapid and sensitive detection of pseudomonas aeruginosa using phage as highly specific recognition agent.
A virulent phage named as PaP1 was isolated from hospital sewage based on a lambda phage isolation protocol. This phage showed a strong and highly specific binding ability to Pseudomonas aeruginosa (P. aeruginosa). Using this isolated phage as a recognition agent, a novel electrochemiluminescent (ECL) biosensor was developed for label-free detection of P. aeruginosa. The biosensor was fabricated through depositing phage-conjugated carboxyl graphene onto the surface of a glass carbon electrode. After specific binding of the host bacteria through the adsorption of P. aeruginosa cell wall by phage tail fibers and baseplate, the ECL signal of luminol suffered a decrease since the formed non-conductive biocomplex obstructed the interfacial electron transfer and blocked the diffusion of the ECL active molecules. The ECL emission declined linearly with P. aeruginosa concentration in the range of 1.4×102-1.4×106CFUmL-1, with a very low detection limit of 56CFUmL-1. The whole detection process could be completed within 30min as a ready-for-use biosensor was adopted. This biosensor was successfully applied to quantitate P. aeruginosa in milk, glucose injection and human urine with acceptable recovery values ranging from 78.6% to 114.3%.
Key Laboratory of Luminescence and Real-Time Analytical Chemistry (Ministry of Education), College of Pharmaceutical Sciences, Southwest University, Chongqing 400716, China.
Huan
H
Yue
Key Laboratory of Luminescence and Real-Time Analytical Chemistry (Ministry of Education), College of Pharmaceutical Sciences, Southwest University, Chongqing 400716, China.
Yong
Y
He
Key Laboratory of Luminescence and Real-Time Analytical Chemistry (Ministry of Education), College of Pharmaceutical Sciences, Southwest University, Chongqing 400716, China.
Enci
E
Fan
Key Laboratory of Luminescence and Real-Time Analytical Chemistry (Ministry of Education), College of Pharmaceutical Sciences, Southwest University, Chongqing 400716, China.
Lin
L
Wang
Department of Microbiology, College of Basic Medical Science, Third Military Medical University, Chongqing 400038, China. Electronic address: shulang88@126.com.
Shuguang
S
Lu
Key Laboratory of Luminescence and Real-Time Analytical Chemistry (Ministry of Education), College of Pharmaceutical Sciences, Southwest University, Chongqing 400716, China. Electronic address: fuzf@swu.edu.cn.
Zhifeng
Z
Fu
D000818:Animals; D001435:Bacteriophages / Q000737:chemistry*; D015374:Biosensing Techniques / Q000379:methods*; D002244:Carbon / Q000737:chemistry; D006046:Gold / Q000737:chemistry; D006108:Graphite / Q000737:chemistry; D006801:Humans; D008163:Luminescent Measurements; D008165:Luminol / Q000737:chemistry; D008892:Milk / Q000737:chemistry; D011550:Pseudomonas aeruginosa / Q000302:isolation & purification* / Q000472:pathogenicity; D014556:Urine / Q000382:microbiology
D008165:Luminol; D002244:Carbon; D006046:Gold; D006108:Graphite
Carboxyl graphene; Electrochemiluminescent biosensor; Luminol; Phage; Pseudomonas aeruginosa