Using photoluminescent gold nanodots to detect hemoglobin in diluted blood samples
Journal
Biosensors and Bioelectronics
Journal Volume
43
Pages
38-44
Date Issued
2013
Author(s)
Abstract
In this study we used photoluminescent 11-mercaptoundecanoic acid-bound gold nanodots (11-MUA-Au NDs) to detect hemoglobin through photoluminescence (PL) quenching. The mechanism of quenching, which occurred through redox reactions between the 11-MUA-Au NDs and the Fe(II) atoms of hemin units, was supported by an increase in the signals (G 2.0 and 5.9) of high-spin state Fe(III) ions. The Stern-Volmer quenching constants (Ksv) for hemin, cytochrome c, hemoglobin, and myoglobin were 5.6×107, 1.7×107, 1.6×107, and 6.2×106M-1, respectively, in good agreement with the order of their reduction potentials. When excited at 375nm, the PL intensity of the 11-MUA-Au NDs at 520nm decreased upon increasing the concentration of hemoglobin from 1.0 to 10nM (R2=0.9913). This approach using bovine serum albumin blocked 11-MUA-Au NDs provided a limit of detection for hemoglobin (at a signal-to-noise ratio of 3) of 0.5nM in biological buffer, with great selectivity over other non-heme-containing proteins, including human serum albumin, Β-casein, and carbonic anhydrase. We validated the practicality of this approach through the determination of the concentrations (1.85-2.46mM) of hemoglobin in diluted (106-fold) human blood samples based on PL quenching of Au NDs. This simple, sensitive, and selective approach holds great potential for the diagnosis of several diseases, including anemia, erythrocytosis, and thalassemias. ? 2012 Elsevier B.V.
Subjects
Diluted blood samples; Hemin; Hemoglobin; Photoluminescent gold nanodots
Other Subjects
Blood samples; Bovine serum albumins; Cytochrome c; Gold nanodots; Hemin; High spin state; Human blood samples; Human serum albumins; Limit of detection; PL intensity; Quenching constant; Reduction potential; Stern-Volmer; Blood; Diagnosis; Gold; Iron compounds; Porphyrins; Quenching; Redox reactions; Hemoglobin; beta casein; bovine serum albumin; carbonate dehydratase; cytochrome c; gold nanodot; hemin; hemoglobin; human serum albumin; myoglobin; quantum dot; unclassified drug; article; blood sampling; controlled study; dilution; hemoglobin determination; human; limit of detection; oxidation reduction reaction; photoluminescence; signal noise ratio; validation study; Biosensing Techniques; Blood Chemical Analysis; Equipment Design; Equipment Failure Analysis; Gold; Hemoglobins; Humans; Luminescent Measurements; Metal Nanoparticles; Quantum Dots; Bovinae
Type
journal article