Vol.:(0123456789) 1 3 Journal of Polymers and the Environment https://doi.org/10.1007/s10924-020-01876-8 ORIGINAL PAPER Functionalized Food‑Grade Biopolymer‑Nanosilica Based Hybrid Hydrogels as Sustained Delivery Devices of Rutin Hriday Bera 1,2  · Yasir Faraz Abbasi 3  · Ang Kah Hoong 2  · Low Phoe Be 2  · Tay Juan Wuan 2  · Haifei Guo 1  · Dongmei Cun 1  · Mingshi Yang 1,4  · Leong Yock Seen 2  · Lim Lip Woan 2  · Sia Qing Ying 2 © Springer Science+Business Media, LLC, part of Springer Nature 2020 Abstract Novel tamarind gum (TG) or carboxymethyl tamarind gum (CMTG) blended diethanolamine-functionalized pectin (DFP) based hydrogels reinforced with calcium silicate (CS) were developed for sustained delivery of rutin (RUT). The DFP (D A , 48.7%) and CMTG (DS, 50.0%) were initially synthesized and analyzed through 1 H-NMR, FTIR, XRD and DSC studies. RUT-loaded hybrid hydrogels were subsequently aforded by Ca 2+ -induced gelation protocol. The hydrogels portrayed acceptable RUT entrapping efciency (DEE, 29–43%), delayed eluting behaviour (Q 6h , 65–100%) and variable swelling at 6 h (16–172%), which were signifcantly infuenced by formulation variables. The RUT dissolution profle of the optimized hydrogels (F-5) obeyed Korsmeyer–Peppas kinetic model with anomalous transport driven mechanism. These matrices also demonstrated excellent mucoadhesion property and biodegradability. Furthermore, the hydrogels revealed their smooth but distorted surface morphology and drug-carrier compatibility with attenuated RUT crystallinity. These hydrogels matrices were thus evidenced to be appropriate for the delivery of hydrophobic RUT in its solubilised form. Keywords Tamarind gum · High-methoxyl pectin · Biopolymer modifcation · Calcium silicate · Nutraceuticals Introduction Over the years, rutin (RUT) has widely been utilized as nutraceuticals and food supplements. RUT is comprised of quercetin (favonol) and rutinose (disaccharide) [1]. It is copiously distributed in buckwheat seed, citrus fruits, vegetables and plant-derived beverages. RUT displays remarkable scavenging activities on oxidizing species such as superoxide, hydroxyl and peroxyl radicals. Even- tually, it demonstrates anti-allergic, anti-inflammatory, anti-tumor, anti-bacterial, anti-viral, anti-protozoal, anti- diabetic, hypolipidaemic and vasoactive properties. Unlike other favonoids, RUT never behaves as a prooxidant agent, catalyzing oxygen radical production. Moreover, it is ben- efcial over other favonoids for not being mutagenic and cytotoxic [2]. However, the wide applications of RUT are often restricted owing to its poor aqueous solubility and lim- ited oral bioavailability [1]. Thus, there is an unmet require- ment to develop a suitable vehicle for oral delivery of RUT. Numerous formulations such as polymer matrices loading RUT-phospholipid complexes [3], nanostructured lipid car- riers [4], RUT-casein co-precipitates [5], stealth lipid poly- mer hybrid nanoparticles [6], argpyrimidine-tagged ethylene glycol dimers nanoparticles [7], etc. have been developed to overcome the shortfalls associated with RUT therapy. Cur- rently, biopolymeric hydrogels have emerged as attractive drug-cargos, which ofer the advantages to deliver hydro- phobic molecules for an extended period in their solubilised forms, thereby augmenting their functionality. Pectin is a plant-derived polymer and regularly used to accomplish hydrogels as drug-carriers due to its excellent biodegradability, high biocompatibility, acid stability and appropriate mechanical property [8]. The backbone of pec- tin molecules is primarily composed of linearly connected α-(1–4)-D-galacturonic acid units repetitively interspersed * Hriday Bera hriday.bera1@gmail.com 1 Wuya College of Innovation, Shenyang Pharmaceutical University, Shenyang 110013, Liaoning, China 2 Faculty of Pharmacy, AIMST University, 08100 Semeling, Kedah, Malaysia 3 Faculty of Pharmacy, Hamdard University, Karachi 74600, Pakistan 4 Department of Pharmacy, University of Copenhagen, Copenhagen, Denmark