“…Among natural polymers, collagen is an important adsorbent due to its structure with acid and basic groups and its fibrillar nature (Karmakar et al, 2017). Collagen has been used for preparing grafted‐copolymers (Nakhjiri et al, 2019), interpenetrating networks (IPNs) (Kaur & Jindal, 2018; Mitra et al, 2019), semi‐interpenetrating networks (semi‐IPN) (Claudio‐Rizo, Burciaga‐Montemayor, et al, 2020), aerogels (Yu et al, 2018), hydrogels (Kurdtabar et al, 2015), sponges (Ashokkumar et al, 2016), and composites (Marandi et al, 2013) with high adsorption performance. Besides, theses hydrogels have shown great potential for the removal of hazardous substances such as textile dyes and heavy metal ions (Al‐Mubaddel et al, 2016; Al‐Mubaddel et al, 2017; Reyes‐Ruiz et al, 2020).…”