1. Stephanie L. D’souza, Ranjan Pati, and Suresh Kumar Kailasa * Department of Chemistry, S. V. National Institute of Technology, Surat – 395007, India * Corresponding author, Phone: +91-261-2201730; Fax: +91-261-2227334 E-mail: sureshkumarchem@gmail.com; skk@ashd.svnit.ac.in AgNO3 Sodium Borohydride Ascorbic Acid AA-AgNPs Scheme 1. Schematic representation for the synthesis of AA-Ag NPs. Supporting information of Ascorbic acid functionalized Ag NPs as a probe for colorimetric sensing of glutathione

2. 0.10.51.52.01.0 Concentration(mM) 0oC0oC25 o C50 o C75 o C100 o C Temperature Figure S1. (a) UV-visible absorption spectra of Ag NPs using sodium borohydride (0.1 – 2 mM) as a reducing agent and (b) UV-visible spectra of AA-Ag NPs at different temperature (a) (b)

3. O-H stretching C=O band α-β unsaturated ketone AgNPs Figure S2. FT-IR spectra of (a) ascorbic acid (b) AA-Ag NPs. (a) (b)

4. A 468 /A 397 Figure S3. The absorbance ratio at A 468nm /A 397 nm in the presence of GSH and other different amino acids. Concentration A 468 /A 397 Figure S4. Calibration graph for the quantification of GSH by using AA-Ag NPs as a sensor.

5. Figure S5. Interference study of different amino acid (threonine, lysine, serine, cystine, histidine, glutamic acid, tyrosine, tryptophan) in presence of GSH.