SupplementaryInformation
Glutathione-Protected Hierarchical Colorimetric Response of Gold Nanoparticles: A Simple Assay for Creatinine Rapid Detection by Resonance Light Scattering Technique
Xiaopeng Huang,aYingjie Li,a Jiahong Pan,aFushen Lu,a Yaowen Chen,band Wenhua Gao*ab
a Department of Chemistry, Shantou University, Shantou, Guangdong 515063, China. E-mail: ; Fax: +86-22-82903941; Tel: +86-22-86502774
b Analysis & Testing Center, Shantou University, Shantou, Guangdong 515063, China.
Fig. S1UV-vis absorbance spectra of GSH-protected AuNPs in the presence of different concentrations of creatinine. Conditions: [creatinine]: 0, 1, 100, 120, 250, 500, 800, 1000 μM, [AuNPs]: 0.5×, [GSH]: 0.20μM, pH7.05
Fig. S2 RLS response of different amino acids of the comparison experiment Experimental content: 1. (a) AuNPs + creatinine (100 μM); (b) AuNPs + GSH (0.20μM) +creatinine (100 μM).
2-12: (a) AuNPs + amino acids (1μM) + creatinine (100 μM); (b) AuNPs + GSH (0.20μM) + amino acids (1μM) +creatinine (100 μM);
2: Amino-propionic acid, 3: Leucine, 4: Phenylalanine, 5: Glycine, 6: Arginine, 7: Lysine, 8: Tyrosine, 9: Tryptophan, 10: Threonine, 11: Valine and 12: Histidine.
Each data was recorded in optimal condition ([AuNPs]: 0.5×, pH7.05). Error bars were the standard deviation of three repetitive measurements
Fig. S3 Optimization of experimental conditions.
(A) UV-vis absorbance of AuNPs with different concentrations of GSH protected and creatinine. Conditions: [GSH]: (a)0.30μM, (b) 0.20μMand (c) 0.15μM, [creatinine]: 100 μM, [AuNPs]: 0.5×, pH7.05.
(B) Effect of pH on the ΔIRLS intensity. The pH values of the solutions were controlled by BR buffer solution with different concentration ratio of acid to base in the pH range 5.51-8.53, [GSH]: 0.20 μM, [creatinine]: 100 μM, [AuNPs]: 0.5×.
(C) Effect of AuNPs concentration on the ΔIRLS intensity. Conditions: [GSH]: 0.20μM, [creatinine]: 100 μM, pH7.05.
(D) Optimization of reaction time. Conditions: [GSH]: 0.20μM, [creatinine]: 100, 250, 500, 800, 1000 μM, [AuNPs]: 0.5×, pH7.05.
All experimental conditions were optimal except for the one which was studied. Error bars were the standard deviation of three repetitive measurements
Fig. S4 Response of the assay against several metal ions (50 μM),urea (1μM), ascorbic acid (1 μM) and a mixture of metal ions and urea in the presence of GSH (0.20 μM). Conditions: [AuNPs]: 0.5×, pH7.05
Table S1 Comparison of our assay with other creatinine detection approaches
Methods / Whole analysis time / Detectionlimit(μM) / Linear range (μM) / Ref.
Amperometric biosensor with controlled pore glass elcetrode / Overnight / 25 / 25-750 / 1
Amperometric bisosensor usingpoly (carbamoyl) sulfonate-hydrogel matrix / Overnight / 0.3 / 1-150 / 2
Amperometric biosensor based on ferrocene embedded carbon paste electrode / Over 15h / 0.01 / Up to 15 / 3
Electrochemical sensor with phosphomolybdic-polypyrrole film modified glassy carbon electrode / About 6h / 0.005 / 1-100 / 4
Enzymeless electrochemical sensor / About 3h / 0.5 / 1.8-108 / 5
HPLC with photometric and fluorimetric detectors / About 1.5h / 35.4 / 88-919 / 6
GSH-protected AuNPs / About 35 min / 1.21 / 10-1000 / This assay
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