Thi Bich Tram Nguyen

Agricultural and food by-products are increasingly discussed as resources for circular production, yet their potential as authentic contexts for STEM learning has received less focused attention. This narrative review synthesizes research across integrated STEM education, inquiry- and project-based learning, food-waste education, agricultural and food by-product valorization, and sustainability education. The literature indicates that residues such as fruit peels, cereal residues, rice husk, sugarcane bagasse, and other processing by-products can provide concrete materials and real-world problems through which learners investigate properties, develop explanations, design solutions, test prototypes, analyze quantitative evidence, and consider sustainability trade-offs. Four complementary learning pathways are identified: inquiry into material properties and transformations; project-based valorization of residues; engineering-design challenges involving criteria, constraints, prototyping and testing; and circular-economy learning in which students analyze resource flows and alternative recovery pathways. The synthesis also shows that the educational value of a by-product depends on the learning design rather than on the material alone. A residue becomes a meaningful integrated STEM context when students explicitly connect disciplinary knowledge to an authentic problem and use evidence to justify design decisions. The review proposes a conceptual framework linking by-product identification, scientific inquiry, technological processing, engineering design, mathematical evaluation, and sustainability reflection. The framework provides a basis for future empirical research on by-product-based STEM learning and offers educators a practical route for connecting local agricultural and food-system challenges with STEM and sustainability competencies.

Horseradish peroxidase (HRP)‐mediated oxidative crosslinking of phenolic polymers is widely employed for in situ hydrogel formation but is limited by high cost and poor oxidative stability. In this study, a hemin‐based polymeric conjugate, alginate–histamine–hemin (Alg–His–He), was developed as a peroxide‐tolerant HRP mimic for phenol crosslinking. Histamine was covalently grafted onto alginate via amide bond formation (70.6% substitution), followed by coordination of hemin through Fe–N(imidazole) interactions to form a polysaccharide–ligand–metal conjugate with tunable hemin content. Structural characterization by FT‐IR, Raman, UV–Vis, and XRD confirmed successful conjugate formation. Alg–His–He exhibited significant peroxidase‐like activity toward guaiacol and pyrogallol, with catalytic performance dependent on the Alg–His/He ratio. Although its activity under mild conditions was lower than that of native HRP, Alg–His–He showed substantially higher tolerance to H ₂ O ₂ , maintaining catalytic function at peroxide concentrations that rapidly inactivated HRP. The conjugate efficiently catalyzed the oxidative crosslinking of gelatin–tyramine, enabling rapid and controllable hydrogelation. The resulting hydrogels displayed interconnected porous structures, good stability under physiological conditions, controllable enzymatic degradation, and excellent cytocompatibility. These findings highlight Alg–His–He as a biocompatible and peroxide‐resistant HRP mimic for injectable hydrogels and other biomaterial applications.

Chitosan and alginate have inherent properties that have a tremendous impact on the design of in situ thermal sensitive hydrogels due to their ability to fill complex three-dimensional damaged tissue gaps, which can be applied in the tissue regeneration or drug delivery systems. In this study, pluronic F127-conjugated alginate (Alg-F127) and pluronic F127-conjugated chitosan (CS-F127) copolymers were investigated for their physicochemical characteristics and morphological fibroblast behavior. The structures of the amphiphilic copolymers were characterized by ¹H-NMR. The aqueous copolymer solution could reversibly change its state from sol to gel via hydrophobic interactions at body temperature (35°–37 °C). At the same concentration of two grafted copolymers, the alginate-based hydrogel performed higher resistance to degrade in both PBS buffer and DMEM. Regarding their specific charge, CS-F127 showed higher protein absorption as compared to the Alg-F127 copolymer. The typical characteristic could induce the different morphological cell behaviors on the hydrogel platforms. Interestingly, as an inherent characteristic of fibroblasts, the cells were elongated and migrated directionally on the Alg-F127 scaffold, though both had excellent cytocompatibility. The improved understanding of the influence of polysaccharide structure on cell behavior has a significant impact on the design of biomedical devices and specific tissue regeneration.

In this study, we report that an enzyme-mimicking biocatalyst polyamidoamine (PAMAM) dendrimer G2.0-hematin (G2.0-He) was fabricated successfully. The chemical structure of G2.0-He was verified by ¹H NMR and FT-IR spectroscopy. G2.0-He exhibited a size distribution from to and a zeta potential from 32.5 mV to 25.6 mV along with the enhancement of the hematin conjugation degree. The relative activity of G2.0-He was evaluated based on pyrogallol oxidation reactions at . The results showed that G2.0-He was more stable than horseradish peroxidase (HRP) enzyme in high H₂O₂ concentrations. The HRP-mimic ability of G2.0-He was also confirmed by the catalyzation when preparing catecholic gelatin hydrogels under mild conditions. Moreover, our results also revealed that these hydrogels performed with excellent cytocompatibility in an in vitro study and could be used as a potential scaffold for adhesion and proliferation of fibroblast cells. The obtained results indicated that G2.0-He is a suitable platform for altering the HRP enzyme in several biomedical applications.

Herein, a new process to manufacture multicore micelles nanoparticles reinforced with co-assembly via hydrophobic interaction and electrostatic interaction under the help of ultrasonication was developed. The precise co-assembly between negative/hydrophobic drug and positive charged amphiphilic copolymer based pluronic platform allows the formation of complex micelles structures as the multicore motif with predefined functions. In this study, curcumin was selected as a drug model while positively charged copolymer was based on a pluronic-conjugated gelatin with different hydrophobicity length of Pluronic F87 and Pluronic F127. Under impact of dual hydrophobic and electrostatic interactions, the nCur-encapsulated core–shell micelles formed ranging from 40 nm to 70 nm and 40–100 nm by transmission electron microscopy (TEM) and Dynamic Light Scattering (DLS), respectively. It is found that the structures emerged depended on the relative lengths of the hydrophobic blocks in pluronic. Regarding g2(τ) behavior from DLS measurement, the nanogels showed a high stability in spherical form. Surprisingly, the release profiles showed a sustainable behavior of Cur from this system for drug delivery approaches. In vitro study exhibited that nCur-encapsulated complex micelles increased inhibitory activity against cancer cells growth with IC₅₀ is 4.02 ± 0.11 mg/L (10.92 ± 0.3 µM) which is higher than of free curcumin at 9.40 ± 0.17 mg/L (25.54 ± 0.18 µM). The results obtained can provide the new method to generate the hierarchical assembly of copolymers with incorporated loading with the same property.

Nanogel-based systems loaded with single anticancer drugs display miscellaneous effectiveness in tumor remission, gradually circumventing mutation and resistance in chemotherapy. Hence, the existence of dual-drug delivered nano-sized systems has been contemporaneous with drug development and preceded the conventional-dose chemotherapy. Among outstanding synergistic drug nanoplatforms, thermosensitive copolymer heparin-Pluronic F127 (Hep-F127) co-delivering cisplatin (CDDP) and curcumins (Cur) (Hep-F127/CDDP/Cur) has emerged as a notable candidate for temperature-responsive drug delivery. The procedure was based on the entrapment of curcumin into the hydrophobic core of bio-degradable co-polymer Hep-F127 while the hydrophilic drug CDDP subsequently conjugated to the backbone heparin to form the core-shell structure. The copolymer was characterized by Fourier transform infrared (FT-IR) spectrophotometry, Transmission Electron Microscopy (TEM), and Dynamic Light Scattering (DLS), to corroborate the successful synthesis and via HPLC along with AES-ICP to evaluate the high drug loading along with a controllable release from the nano-gels. A well-defined nano-shell with size in the 129.3 ± 3.8 nm size range could enhance higher the efficacy of the conjugated-CDDP to Hep-F127 than that of single doses. Moreover, the considerable amount of dual-drug released from thermosensitive nanogels between different conditions (pH = 7.4 and pH = 5.5) in comparison to CDDP from Hep-F127 partially indicated the significantly anti-proliferative ability of Hep-F127/CDDP/Cur to the MCF-7 cell line. Remarkably, drug testing in a xenograft model elucidates the intricate synergism of co-delivery in suppressing tumor growth, which remedies some of the problems affecting in cancer chemotherapy.

In this study, in order to enhance the aqueous solubility and to overcome the limitation of curcumin (Cur) in free form, as well as to develop a carrier for transdermal delivery of hydrophobic pharmaceutical agents such as Cur, a sonicated synthetic process of nanocurcumin (nCur) in thermally responsive Chitosan-g-Pluronic (CP) copolymer is disclosed herein. The use of CP copolymer solution as a dispersant medium is a very attractive method to avoid the use of toxic organic solvent and non-biocompatible surfactant. The obtained Cur nanoparticles had a fairly narrow distribution of 8–23 nm. nCur-dispersed CP solution showed good stability with no change in color characteristic and no phase separation after 1 month of storage. Rheological characterization of CP hydrogels had indicated sol-gel transition at the same temperature (35°C). Interestingly, the rate of Cur release for this system can be conveniently modulated as transdermal drug delivery.