# Deposition Efficacy of Natural and Synthetic Antioxidants on Fabrics
## 4 Conclusions  
Pine tannins and commercial antioxidant species were deposited on model fabrics. A dedicated test method, based on the ABTS assay, was developed to determine deposition efficiency and homogeneous distribution of the antioxidant species on the fabric. The developed procedure could be also successfully applied to measure the residual antioxidant activity of the species deposited on fabrics. A known source of odour is autoxidation of residual sebum on fabric, leading to generation of an array of odoriferous compounds [20]. Antioxidants hold thus a promise for mitigating malodour on fabrics, a top unmet consumer need around the globe.  
**Supplementary Materials:** The following are available online at [[http://www.mdpi.com/2076-3417/10/18/6213/s1](http://www.mdpi.com/2076-3417/10/18/6213/s1)]([http://www.mdpi.com/2076-3417/10/18/6213/s1](http://www.mdpi.com/2076-3417/10/18/6213/s1)), Figure S1: Structures of synthetic phenolic antioxidants; Figure S2: ABTS**+**decolorization assay before and after addition of MBHPP (1 mg/mL in ethanol); Figure S3: **PST-SW1** calibration plot for evaluation of amount of active tannin deposited on fabric.  
**Author Contributions:** Conceptualisation, G.B. and C.C.; methodology, P.G.; H.L.; G.B. and C.C.; validation, P.G.; H.L.; G.B. and C.C.; formal analysis, P.G.; H.L. and C.J.; investigation, P.G.; H.L.; C.J. and D.W.B.; resources, G.B. and C.C.; data curation, P.G. and H.L.; writing--original draft preparation, P.G; H.L. and C.C.; writing--review and editing, P.G; H.L.; G.B. and C.C.; supervision, H.L. and C.C.; funding acquisition, G.B. and C.C. All authors have read and agreed to the published version of the manuscript.  
**Funding:** General financial support by the Procter & Gamble Company is gratefully acknowledged.  
\begin{table}
\begin{tabular}{c c c c c} \hline \hline \multirow{2}{*}{**Entry**} & \multirow{2}{*}{**Fabric**} & \multirow{2}{*}{**Sample (10 mg)**} & **Amount of Pine Tannin** & **Amount of Pine Tannin** \\  & & & **Deposited on 10.0 mg** & **Deposited on 10.0 mg Fabric** [**ug**] & **Deposited on 10.0 mg Fabric** \\ \hline
1 & **PST-SW1\_cotton\_H\({}_{2}\)O** & & & \\  & mechanical & 1 & 0.25 & \\
2 & **PST-SW1\_cotton\_H\({}_{2}\)O** & & & \\
3 & **PST-SW1\_cotton\_H\({}_{2}\)O** & & & \\  & mechanical & 3 & 0.49 & \\
4 & **PST-SW1\_cotton\_H\({}_{2}\)O** & & & \\  & mechanical & 4 & 0.13 & \\
5 & **PST-SW1\_cotton\_H\({}_{2}\)O** & & & \\  & mechanical & 5 & 0.09 & \\ \hline
6 & **PST-SW1\_cotton\_H\({}_{2}\)** & 1 & 0.25 & \\
7 & **PST-SW1\_cotton\_H\({}_{2}\)** & 2 & 0.21 & \\ \hline
8 & BHT cotton\_H\({}_{2}\)O & 1 & 0.27 & \\
9 & BHT cotton\_H\({}_{2}\)O & 2 & 0.17 & \\
10 & BHT cotton\_H\({}_{2}\)O & 3 & 0.22 & \\
11 & BHT cotton\_H\({}_{2}\)O & 4 & 0.15 & \\ \hline
12 &
\begin{tabular}{c} Cctadecyl 3-(3,5-di-tert-butyl-4- \\ hydroxyl-phenyl)propanoate \\ cotton\_H\({}_{2}\)O \\ \end{tabular} & 1 & 0.15 & \\
13 &
\begin{tabular}{c} Cctadecyl 3-(3,5-di-tert-butyl-4- \\ hydroxyl-phenyl)propanoate \\ cotton\_H\({}_{2}\)O \\ \end{tabular} & 2 & 0.14 & \\
14 &
\begin{tabular}{c} Cctadecyl 3-(3,5-di-tert-butyl-4- \\ hydroxyl-phenyl)propanoate \\ cotton\_H\({}_{2}\)O \\ \end{tabular} & 3 & 0.14 & \\
15 &
\begin{tabular}{c} Cctadecyl 3-(3,5-di-tert-butyl-4- \\ hydroxyl-phenyl)propanoate \\ cotton\_H\({}_{2}\)O \\ \end{tabular} & 4 & 0.13 & \\ \hline \hline \end{tabular}
\end{table}
Table 5: Amount of antioxidants deposited on fabric determined by ABTS**+**decolourisation assay.  
**Acknowledgments:** The authors thank Robertet SA R&D Department (Grasse, France) for providing _Pinus syhestris_ tannin sample (**PST-sW1**). H.L. acknowledges the MIUR Grant 'Dipartimento di Eccellenza 2018-2022' to the Department of Pharmacy of the University of Naples 'Federico II'. C.C acknowledges the Ca'Foscari FPI 2019 funding.  
**Conflicts of Interest:** The authors declare no conflict of interest.