Quantitative detection of free 24S-hydroxycholesterol, and 27-hydroxycholesterol from human serum

Abstract A modification of the mouse fetal liver cell bioassay for erythropoietin (ESF) that allows quantitative detection of ESF in human serum is described. The modification consists of (1) correction for the effect of serum iron on 59Fe incorporation into heme and (2) the use of an “internal standard,” i.e., a standard ESF preparation dissolved in the assayed test serum. As a result of this modification the statistical method of bioassay analysis had to be changed fundamentally. The mean serum concentration of ESF measured in 20 normal males was 48 microunit/ml, as compared to 29 microunit/ml in 18 females. The difference was significant at p = 0.017. The stimulatory activity of a human serum on 59Fe incorporation into heme could be neutralized by an anti-human ESF immune serum.

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Functionalized nanoporous gold as a new biosensor platform for ultra-low quantitative detection of human serum albumin

Sensors and Actuators B Chemical ◽

10.1016/j.snb.2019.03.005 ◽

2019 ◽

Vol 288 ◽

pp. 460-468 ◽

Cited By ~ 7

Author(s):

F. Scaglione ◽

E. Alladio ◽

A. Damin ◽

F. Turci ◽

C. Baggiani ◽

...

Keyword(s):

Human Serum Albumin ◽

Serum Albumin ◽

Human Serum ◽

Nanoporous Gold ◽

Quantitative Detection

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Reusable, Noninvasive, and Sensitive Fluorescence Enhanced ZnO-Nanorod-Based Microarrays for Quantitative Detection of AFP in Human Serum

BioMed Research International ◽

10.1155/2021/9916909 ◽

2021 ◽

Vol 2021 ◽

pp. 1-11

Author(s):

Saima Rafique ◽

Farukh Kiyani ◽

Sumbal Jawaid ◽

Rubina Nasir ◽

Mahmoosh Ahmad ◽

...

Keyword(s):

Human Serum ◽

Dynamic Range ◽

Limit Of Detection ◽

Zno Nanorods ◽

Protein Microarrays ◽

Great Promise ◽

Quantitative Detection ◽

Zno Nanorod ◽

Serum Samples ◽

Protein Assay

The fabrication of sensitive protein microarrays such as PCR used in DNA microarray is challenging due to lack of signal amplification. The development of microarrays is utilized to improve the sensitivity and limitations of detection towards primal cancer detection. The sensitivity is enhanced by the use of ZnO-nanorods and is investigated as a substrate which enhance the florescent signal to diagnose the hepatocellular carcinoma (HCC) at early stages. The substrate for deposition of ZnO-nanorods is prepared by the conventional chemical bath deposition method. The resultant highly dense ZnO-nanorods enhance the fluorescent signal 7.2 times as compared to the substrate without ZnO-nanorods. The microarray showed sensitivity of 1504.7 ng ml-1 and limit of detection of 0.1 pg ml-1 in wide dynamic range of 0.05 pg-10 μg ml-1 for alpha fetoprotein (AFP) detection in 10% human serum. This immunoassay was successfully applied for human serum samples to detect tumor marker with good recoveries. The ZnO-nanorod substrate is a simple protein microarray which showed a great promise for developing a low-cost, sensitive, and high-throughput protein assay platform for several applications in both fundamental research and clinical diagnosis.

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Solid-phase enzyme-receptor assay (SPERA): a competitive-binding assay for glycopeptide antibiotics of the vancomycin class.

Clinical Chemistry ◽

10.1093/clinchem/31.10.1606 ◽

1985 ◽

Vol 31 (10) ◽

pp. 1606-1610 ◽

Cited By ~ 16

Author(s):

A Corti ◽

C Rurali ◽

A Borghi ◽

G Cassani

Keyword(s):

Human Serum ◽

Binding Assay ◽

Solid Phase ◽

Quantitative Detection ◽

Synthetic Analog ◽

Bacterial Cells ◽

Glycopeptide Antibiotics ◽

Competitive Binding Assay ◽

Analytical Recovery ◽

Receptor Assay

Abstract A solid-phase enzyme-receptor assay (SPERA) has been developed for glycopeptide antibiotics of the vancomycin class such as teicoplanin, vancomycin, ristocetin, avoparcin, actaplanin, A-47934, A-41030, and A-35512-B. The assay exploits the mechanism of most action of these antibiotics, which is based on their interaction with acyl-D-alanyl-D-alanine, a constituent of the walls of most growing bacterial cells. The antibiotics and enzyme-labeled teicoplanin compete for a synthetic analog of the biological receptor, albumin-epsilon-aminocaproyl-D-alanyl-D-alanine. The various antibiotics produced different competition curves, 50% displacement being obtained with antibiotic concentrations ranging from 0.04 to 4 mg/L, vancomycin and actaplanin being the weakest and strongest competitors, respectively. For teicoplanin in human serum the intra-assay CV was 7.2%, the interassay CV was 11.2%, and the analytical recovery 94%. Teicoplanin concentrations obtained by SPERA (chi) correlated well with those obtained by microbiological assay (y): y = 1.03 chi + 0.053 (r = 0.943; n = 60). We conclude that SPERA is a powerful tool for identification and quantitative detection of glycopeptide antibiotics, even in complex media.

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