## 4 Conclusions  
Alginate and polypyrrole hydrogel composites (ALG, PPy-ALG and ALG@PPy hydrogel beads) were successfully prepared and characterized. As a future application  
Figure 4: GC-MS peak area (replicates = 2) of CAF, ATZ, and PRO (0.5 mg mL\({}^{-1}\)) after extraction using ALG, PPy-ALG and ALG@PPy hydrogel beads in (**a**) ultrapure water, (**b**) HCl 0.1 mol L\({}^{-1}\) and (**c**) NaCl 0.1 mol L\({}^{-1}\). The order of increasing polarity of the contaminants is: CAF > ATZ > PRO.  
perspective, the composite hydrogels were employed as the sorbent phase for ATZ, CAF, and PRO, and showed potential for the extraction of compounds with different polarities from aqueous matrices. The physical-chemical properties of these materials indicate that the hydrogel matrix and its functional groups, associated with the conducting polymer chains, are very important to ensure satisfactory amphiphilic interactions with the analytes.  
The following supporting information can be downloaded at: [[https://www.mdpi.com/article/10.3390/app122010609/s1](https://www.mdpi.com/article/10.3390/app122010609/s1)]([https://www.mdpi.com/article/10.3390/app122010609/s1](https://www.mdpi.com/article/10.3390/app122010609/s1)), Detailed description of the protocols for hybrid hydrogels formation, Table S1: HPSEC-MALLS information of sodium alginate; Figure S1: HPSEC profiles of sodium alginate obtained from Sigma-Aldrich; Figure S2: UV-Vis spectra for PPy-ALG dispersion synthesis; Figure S3: FTIR spectrum of sodium alginate and PPy-ALG composite; Figure S4: Scanning electron microscopy images: (a) neat ALG, (b) neat PPy, and (c) PPy-ALG composite; Figure S5: Loss of water (in wt%) of ALG, PPy-ALG and ALG@PPy hydrogels at 60 \({}^{\circ}\)C (replicates = 3); Figure S6: Representative chromatogram showing peaks for ATZ, CAF, and PRO for extraction performed with ALG, PPy-ALG and ALG@PPy beads in ultrapure water.  
Conceptualization, B.J.G.S., M.V. and I.C.R.-V.; methodology, B.J.G.S., M.V. and I.C.R.-V.; investigation, S.C.J., A.C.d.L. and N.M.F.M.S.; resources, B.J.G.S., M.V. and I.C.R.-V.; data curation, S.C.J., A.C.d.L. and N.M.F.M.S.; writing--original draft preparation, S.C.J.; writing--review and editing, G.A.J.; visualization, G.G.A.J.; supervision, B.J.G.S., L.F.M., M.V. and I.C.R.-V.; project administration, B.J.G.S., M.V. and I.C.R.-V. All authors have read and agreed to the published version of the manuscript.  
The authors gratefully acknowledge CTI-Nano, strategic laboratory from SisNano, MCTI financed by CNPq, UFPR Electron Microscopy Center (CME-UFPR). CNPq is also acknowledged for financial support, grants 312501/2020-0, 303038/2019-5, and 408635/2018-5 and Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior--Brasil (CAPES)--Finance Code 001. Also, INCT in Bioanalytics (FAPESP grant no. 2014/50867-3 and CNPq grant no. 465389/2014-7), FAPESP (CEPID--CDMF 2013/07296-2), are kindly acknowledged.  
Not applicable.  
The authors are very grateful to [PERSON] for fruitful discussions, [PERSON] for the GPC/SEC experiments, and UFPR Electron Microscopy Center (CME-UFPR) for the microscopy images.  
The authors declare no conflict of interest. The funders had no role in the design of the study; in the collection, analyses, or interpretation of data; in the writing of the manuscript; or in the decision to publish the results.