Dual-probe (colorimetric and fluorometric) detection of ferritin using antibody-modified gold@carbon dot nanoconjugates
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A dual-mode assay is described for immunological determination of the anemia biomarker ferritin. It is based on the use of a gold@carbon dot (Au@CD) nanoconjugate as a colorimetric and fluorescent probe. Au@CD is hydrophilic, easily surface modified and stable in aqueous solution. The Au@CD have a red color with blue-green fluorescence and were modified with antibody against ferritin. This allows bi-modal detection of ferritin. Assays can be performed in phosphate buffer and were also analyzed in (Bovine Serum Albumin) BSA and (Fetal Bovine Serum) FBS. Detection is based on antigen-antibody interaction underlying the classical sandwich model. Response to ferritin can be detected by spectrophotometry (at 570 nm) or fluorescence (at excitation/emission maxima of 354/454 nm). Under optimal conditions, the assay has a linear response in the 1 to 120 ngmL−1 ferritin concentration range and detection limits of 20 ng (colorimetrically) and 64 ng (fluorometrically).
KeywordsBi-modal detection Antigen-antibody Immunoassay Anemia Nanoprobe Diagnostic sensor Binding efficiency Dynamic light scattering Aggregation Quenching
EP is thankful to DST-SERB for National Postdoctoral Fellowship under the grant number PDF/2017/000024. The authors thank the Advanced Instrument Research Facility of the University for Analytical Characterization.
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Conflict of interest
The author(s) declare that they have no competing interests.
- 8.Wang X, Xu R, Sun X, Wang Y, Ren X, Du B, Wu D, Wei Q (2017) Using reduced graphene oxide-Ca:CdSe nanocomposite to enhance photo electrochemical activity of gold nanoparticles functionalized tungsten oxide for highly sensitive prostate specific antigen detection. Biosens Bioelectron 96:239–245CrossRefGoogle Scholar
- 16.Holtzman DM, Morris JC, Goate AM (2011) Alzheimer’s disease: the challenge of the second century. Sci Transl Med 3:77Google Scholar
- 23.Shyh-Dar L, Huang L (2011) Stealth nanoparticles: high density but shed dable PEG is a key for tumor targeting. J Control Release 145(3):178–181Google Scholar