Highly Sensitive and Selective Electrochemical Detection of L-Cysteine Using Nanoporous Gold

Electronic Supplementary Material

Highly sensitive and selective electrochemical detection of L-cysteine using nanoporous gold

Zhaona Liua, Huacheng Zhanga, Shifeng Houb, Houyi Maa,* aKey Laboratory for Colloid and Interface Chemistry of State Education Ministry, School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100, China bDepartment of Chemistry and Biochemistry, Montclair State University, Montclair, NJ 07043, USA

* Corresponding author: Fax: +86-531-88564464; E-mail: [email protected]

Fig. S-1 CVs for bulk gold electrode in 0.2 M phosphate buffer (pH 7.0) with (solid lines) and without (dotted lines) 1.0 mM CySH. Fig. S-2. Current responses obtained at the NPG/GC in 0.2 M phosphate buffer (pH 7.0) with the additions (indicated by arrows) of (left to right) 5 μM CySH, 5 μM CySH, 5 μM ascorbic acid , 5μM methionine, 5 μM uric acid and 10 μM CySH. Applied potential: 0.65 V.

Table S-1. Recovery studies of CySH in the presence of human urine (n = 3)

Sample CySH Added CySH Found Recovery (%) (μM) (μM) Human urine 2 2.20 107 4 4.11 103 6 5.98 99.7 8 7.88 98.5 10 9.83 98.3