title: Indirect electrochemical detection for total bile acids in human serum.
abstract: Bile acids level in serum is a useful index for screening and diagnosis of hepatobiliary diseases. As bile acids concentration is closely related to the degree of hepatobiliary diseases, detecting it is a vital factor to understand the stage of the diseases. The prevalent determination for bile acids is the enzymatic cycling method which has low sensitivity while reagent-consuming. It is desirable to develop a new method with lower cost and higher sensitivity. An indirect electrochemical detection (IED) for bile acids in human serum was established using the screen printed carbon electrode (SPCE). Since bile acids do not show electrochemical signals, they were converted to 3-ketosteroids by 3-α-hydroxysteroid dehydrogenase (3α-HSD) in the presence of nicotinamide adenine dinucleotide (NAD(+)), which was reduced to NADH. NADH could then be oxidized on the surface of SPCE, generating a signal that was used to calculate the total bile acids (TBA) concentration. A good linear calibration for TBA was obtained at the concentration range from 5.00μM to 400μM in human serum. Both the precisions and recoveries were sufficient to be used in a clinical setting. The TBA concentrations in 35 human serum samples by our IED method didn't show significant difference with the result by enzymatic cycling method, using the paired t-test. Moreover, our IED method is reagent-saving, sensitive and cost-effective.
authors.affiliation: Key Laboratory of Clinical Laboratory Diagnostics (Ministry of Education of China), College of Laboratory Medicine, Chongqing Medical University, Chongqing 400016, PR China.
authors.forename: Xiaoqing
authors.initials: X
authors.lastname: Zhang
authors.affiliation: Department of Clinical Laboratory of Chongqing General Hospital, Chongqing 408000, PR China.
authors.forename: Mingsong
authors.initials: M
authors.lastname: Zhu
authors.affiliation: Department of Clinical Laboratory of the First Affiliated Hospital of Chongqing Medical University, Chongqing 400016, PR China.
authors.forename: Biao
authors.initials: B
authors.lastname: Xu
authors.affiliation: Key Laboratory of Clinical Laboratory Diagnostics (Ministry of Education of China), College of Laboratory Medicine, Chongqing Medical University, Chongqing 400016, PR China.
authors.forename: Yue
authors.initials: Y
authors.lastname: Cui
authors.affiliation: Key Laboratory of Clinical Laboratory Diagnostics (Ministry of Education of China), College of Laboratory Medicine, Chongqing Medical University, Chongqing 400016, PR China.
authors.forename: Gang
authors.initials: G
authors.lastname: Tian
authors.affiliation: Key Laboratory of Clinical Laboratory Diagnostics (Ministry of Education of China), College of Laboratory Medicine, Chongqing Medical University, Chongqing 400016, PR China.
authors.forename: Zhenghu
authors.initials: Z
authors.lastname: Shi
authors.affiliation: Key Laboratory of Clinical Laboratory Diagnostics (Ministry of Education of China), College of Laboratory Medicine, Chongqing Medical University, Chongqing 400016, PR China. Electronic address: dingmin@cqmu.edu.cn.
authors.forename: Min
authors.initials: M
authors.lastname: Ding
mesh_terms: D045002:3-alpha-Hydroxysteroid Dehydrogenase (B-Specific) / Q000378:metabolism; D001647:Bile Acids and Salts / Q000097:blood* / Q000378:metabolism; D015374:Biosensing Techniques / Q000295:instrumentation; D055664:Electrochemical Techniques / Q000295:instrumentation*; D004566:Electrodes; D004867:Equipment Design; D006801:Humans; D057230:Limit of Detection; D009243:NAD / Q000378:metabolism
chemical_list: D001647:Bile Acids and Salts; D009243:NAD; D045002:3-alpha-Hydroxysteroid Dehydrogenase (B-Specific)
keywords: Bile acids; Indirect electrochemical detection (IED); Reduced nicotinamide adenine dinucleotide (NADH); Screen printed carbon electrode (SPCE)