U.V-vis spectra of HRP with different concentration of Ag-NPs.

<p>The U.V-vis spectra of the interaction of HRP with different concentration of Ag-NPs were recorded as mentioned in the text. The concentration range was from 0.04 to 0.16 mM of Ag-NPs. The alphabets presents different concentrations of nanoparticles; a- 0.08 mM, b-0.06 mM, c-0.10 mM, d-0.12 mM, e-enzyme, f-0.04 mM, g- 0.14 mM, h-0.16 mM and i-nanoparticle.</p

TEM spectra of prepared Ag-NPs.

<p>The TEM spectra were monitor as described in the text with magnification of 500000×.</p

Particle size distributions of Ag-NPs prepared using chemical reduction method.

<p>The figure confirms the formation of approx 20 nm silver nanoparticles by chemically reduction method.</p

FT-IR spectra of chemically synthesized Ag-NPs and bound Ag-NPs with HRP.

<p>FT-IR spectra were measured as described in the text. The freshly prepared native Ag-NPs and bound with HRP samples were recorded using KBr pelleting technique with Perkin Elmer System 2000 instrument in range of 400–4000 cm⁻¹. Figures demonstrate the native Ag-NPs (a) and bound Ag-NPs with HRP (b).</p

UV-vis spectra of Ag-NPs with time; (a) 20 (b) 40 and (c) 60 min.

<p>The synthesis of Ag-NPs was performed as described in the text.</p

Determination of α-helix relative content (%).

<p>The α-helix relative content (%) was determined as mentioned in the text. The increase in the α-helix relative contents also supports our hypothesis.</p

Fluorescence spectra measurement.

<p>Fluorescence spectra were recorded as described in the text with the different concentration of Ag-NPs. For alphabetic representation please refer to Fig. 5. The increase in the fluorescence intensity was in the support of our hypothesis.</p

Effect of Ag-NPs concentrations on the activity of HRP.

<p>The immobilization of HRP with different concentrations of Ag-NPs was performed as described in the text. The concentration range that was selected for the immobilization was 0.04–0.16 mM of silver nanoparticles.</p

Adsorbent dosage effect on the sorption of Methylene Blue by AC and FeAC.

<p>Adsorbent dosage effect on the sorption of Methylene Blue by AC and FeAC.</p

Determination of the pH of zero point of charge (pH_<i>ZPC</i>) for AC and FeAC.

<p>Determination of the pH of zero point of charge (pH_<i>ZPC</i>) for AC and FeAC.</p