bims-livmat 2026-04-05 papers

bims-livmat

Biomed News

on Living materials

Issue of 2026–04–05
ten papers selected by
Sara Trujillo Muñoz, Leibniz-Institut für Neue Materialien

Engineered biofilm-based living hydrogel for bioprinting.
Autonomous Cargo Transport with Biohybrid Microswimmers Enabled by Light-Mediated Bacteria-Cargo Communication.
Living Hydrogels: Harnessing Microorganism-Material Synergy for Next-Generation Therapeutics.
Polysaccharide-based live hydrogels for probiotic intestinal and wound therapy.
Natural polymer-based encapsulation system for Lactiplantibacillus plantarum HD51: Enhanced gastrointestinal stability and functional bioactivity.
Electrospray encapsulation of Lactobacillus plantarum in alginate-starch-pectin hydrogels for enhanced gastric protection and intestinal delivery.
Microencapsulation of probiotics using crosslinked lotus seed starch and alginate: protection and structural evolution during digestion.
An artificial mucus-integrated in vitro model enables stable live probiotic-host co-culture and recapitulates dynamic hBD-2-mediated antimicrobial feedback.
Engineered bilayer hydrogel with spatiotemporal drug and oxygen delivery for diabetic wound microenvironment reprogramming.
Optical analysis of bacterial metabolic activity and spore germination via formazan formation.

Colloids Surf B Biointerfaces. 2026 Mar 30. pii: S0927-7765(26)00254-7. [Epub ahead of print]264 115666

Engineered biofilm-based living hydrogel for bioprinting.

Xinxin Hao, Zahra Abdali, Mario Alfonso Arenas Garcia, Dalia Jane Saldanha, Coralie Jabra Khabbaz, Noémie-Manuelle Dorval Courchesne.

  Incorporating genetically modifiable microbial biomass with polymeric hydrogel matrices offers a simple strategy for both bottom-up and top-down approaches in functional living hydrogel materials design. In this work, we designed a two-part living hydrogel, consisting of a non-living hydrogel matrix and engineered living biofilms. We used polyvinylpyrrolidone (PVP), gelatin, and agar to make a composite polymeric hydrogel matrix. Then we incorporated genetically engineered functional Escherichia coli (E. coli) biofilms containing cells and curli fibers into the hydrogel matrix. We investigated the physical and mechanical properties of the living hydrogel material with various formulations. The results showed that this viscoelastic living hydrogel with shear-thinning properties and storage modulus in the range between a few hundred and thousand Pa was suitable for extrusion-base bioprinting. The living hydrogel can absorb water about 5 times its dry weight and disintegrate quickly by 50% within 8 h of water immersion. We also demonstrated that the incorporated cells maintained their viability and ability to express recombinant curli fusion proteins after printing. The incorporated genetically engineered biofilms also maintained their fluorescence and pH response. This work provides a promising foundation for the development of functional living materials and can serve as a useful reference for environmental sensing applications requiring responsive and biologically active hydrogel systems.

Keywords:  Biofilm; Bioprinting; Engineered living materials; Living hydrogels; Responsive hydrogels

DOI:  https://doi.org/10.1016/j.colsurfb.2026.115666
Adv Mater. 2026 Mar 30. e72950

Autonomous Cargo Transport with Biohybrid Microswimmers Enabled by Light-Mediated Bacteria-Cargo Communication.

Xiaoran Zheng, Yanjun Zheng, Ali Heidari, Seraphine V Wegner.

  Biohybrid microswimmers, which integrate the unique mobility and taxis of living cells with the versatility of synthetic cargo, offer exciting opportunities for targeted delivery. However, current biohybrids lack autonomous decision-making capabilities due to the absence of communication between living and synthetic components. Here, we report biohybrid microswimmers capable of self-regulating cargo pickup, transport, and release through light-mediated communication between bacteria and cargo. The genetically engineered Escherichia coli bacteria act as senders, converting dynamic changes in the concentration of a model toxin, Hg2+, into a cellular light signal. The cargo, composed of small unilamellar vesicles (SUVs), is functionalized with a photoswitchable membrane-binding protein to perceive the light signal. By interfacing the two components, the bacteria can dynamically signal the presence of Hg2+ to the SUVs, triggering their attachment to bacteria and biohybrid assembly. The inherent negative chemotaxis of bacteria to Hg2+ directs the transport of cargo toward low Hg2+ environments, where the cessation of light signaling prompts cargo release. This autonomous cargo transport is governed by an emerging self-regulatory network, combining light-mediated communication between cargo and bacteria with bacterial chemotaxis. The modular biohybrid microswimmer design paves the way for advanced microrobotic systems in which synthetic and living components coordinate their actions.

Keywords:  BcLOV4; autonomous cargo delivery; biohybrids; light‐mediated communication; microrobots

DOI:  https://doi.org/10.1002/adma.72950
Adv Sci (Weinh). 2026 Apr 02. e21766

Living Hydrogels: Harnessing Microorganism-Material Synergy for Next-Generation Therapeutics.

Shuifang Mao, Bingyao Bai, Xingqian Ye, Yiliang Lin.

  Microorganism-based therapies, particularly those utilizing probiotics, have emerged as a powerful biomedical strategy owing to their inherent living functionalities. These living systems can dynamically interact with host environments and self-regulate their activity, offering superior adaptability, prolonged functionality, and microenvironmental responsiveness compared to conventional non-living therapeutic platforms. Despite these advantages, the direct administration of probiotics faces several challenges, such as poor viability, limited retention at target sites, and the inability to control therapeutic effects in a spatiotemporally precise manner. To address these challenges, embedding probiotics within hydrogel matrices has proven effective in enhancing microbial stability, prolonging in vivo retention, and enabling precise and sustained therapeutic delivery through synergistic interactions between the hydrogels and living microorganisms. This review provides a comprehensive overview of the materials and design strategies employed in the construction of living microorganism-encapsulated hydrogels (living hydrogels), with particular emphasis on the dynamic interactions and synergistic mechanisms of hydrogel-microorganism systems. We further illustrate how these mechanisms can achieve various biomedical applications, such as modulating gut microbiota to treat gastrointestinal disease and accelerate wound healing, or leveraging microbial-induced immune regulation for effective cancer therapy. Finally, the current challenges and future directions associated with the clinical translation of living hydrogels are highlighted. Therefore, the unique multifunctionality and therapeutic promise of living hydrogels position them as compelling candidates for the development of next-generation biomaterials with unprecedented therapeutic potential.

Keywords:  biological application; dynamic interaction; living hydrogels; synergistic mechanism

DOI:  https://doi.org/10.1002/advs.202521766
Int J Biol Macromol. 2026 Mar 30. pii: S0141-8130(26)01649-1. [Epub ahead of print] 151723

Polysaccharide-based live hydrogels for probiotic intestinal and wound therapy.

Jiajia Xu, Yang Huang, Yuqian Liu, Huining Xiao, Farzad Seidi.

  Probiotics as therapeutic microorganisms have been widely used for gastrointestinal disorders and wound therapy. However, poor viability in wound and gastrointestinal environments limits their efficacy. Polysaccharide-based hydrogels are suitable delivery systems for probiotics to overcome these challenges. These hydrogels by benefiting from their biocompatibility, biodegradability, and non-toxicity can create suitable microenvironments for probiotics. Unlike passive traditional carriers (such as capsules or inert nanoparticles), these "live hydrogels" are dynamic carriers encapsulating viable cells as bioreactors for sustained metabolite production. This review systematically studies the design, fabrication, and application of such live hydrogels for intestinal and wound therapy. Intestinal therapy emphasizes ionic-crosslinking along with co-encapsulation with protective agents (such as prebiotics and antacids) to improve cell viability and pH-responsive release of cells to restore gut microbiota and combat infections. On the other hand, in wound management, the release of probiotics is prevented to avoid the immune responses. Instead, these live hydrogels act as bioreactors for sustained production of release of therapeutic metabolites. New approaches such as antioxidant coatings and genetic engineering can further improve the efficacy of probiotics. However, the long-term viability, biosafety, and clinical translation remain challenges that need to be addressed.

Keywords:  Polysaccharide hydrogels; Probiotics; Wound/intestinal therapy

DOI:  https://doi.org/10.1016/j.ijbiomac.2026.151723
Food Sci Technol Int. 2026 Mar 29. 10820132261434782

Natural polymer-based encapsulation system for Lactiplantibacillus plantarum HD51: Enhanced gastrointestinal stability and functional bioactivity.

Sonika Thoudam, Karuthapandian Devi, Chand Ram Grover.

  This study developed a natural polymer-based microencapsulation system for Lactiplantibacillus plantarum HD51 using alginate, skimmed milk and flaxseed mucilage. Four formulations were evaluated for encapsulation efficiency, gastrointestinal survivability, release behaviour, exopolysaccharide production, antimicrobial activity, storage stability and pancreatic lipase inhibitory potential. The composite matrix (Alg-SM-FM) achieved the highest encapsulation efficiency (95.54%) and exhibited improved protection of probiotic cells under simulated gastric and intestinal conditions compared with single-component systems. Scanning electron microscopy revealed a denser and more compact microstructure in composite formulations, indicating enhanced physical protection. Encapsulated probiotics maintained viable counts above 107 CFU/g, showed controlled release in simulated intestinal fluid and retained antimicrobial activity and exopolysaccharide-producing capability. Multivariate analysis using principal component analysis revealed clear associations between formulation composition and key functional attributes, including encapsulation efficiency, bead size, survivability and bioactivity. Additionally, encapsulated Lactiplantibacillus plantarum HD51 demonstrated measurable pancreatic lipase inhibitory activity, suggesting potential relevance for metabolic health applications. Overall, the results indicate that combining alginate with dairy- and plant-derived biopolymers provides a promising food-grade strategy for enhancing probiotic stability and functionality in functional food and nutraceutical applications.

Keywords:  Alginate–protein composite; exopolysaccharide (EPS); flaxseed mucilage; functional food matrix

DOI:  https://doi.org/10.1177/10820132261434782
Int J Biol Macromol. 2026 Mar 31. pii: S0141-8130(26)01683-1. [Epub ahead of print] 151757

Electrospray encapsulation of Lactobacillus plantarum in alginate-starch-pectin hydrogels for enhanced gastric protection and intestinal delivery.

Farzaneh Namazifar, Azizollah Shafiekhani, Fakhrisadat Hosseini.

  The therapeutic efficacy of orally administered probiotics is severely limited by their inactivation in the acidic gastric environment, making protective delivery systems essential for effective intestinal colonization. In this study, a pH-responsive microencapsulation strategy was developed for Lactobacillus plantarum (ATCC 8014) using a peristaltic pump-assisted electrospray technique. Two food-grade hydrogel matrices were formulated: a binary alginate-starch (AS) system and a novel ternary alginate-pectin-starch (APS) system. Uniform spherical microcapsules were produced, with mean diameters of 454.7 ± 94.9 μm (AS) and 586.7 ± 65.2 μm (APS). Fourier-transform infrared spectroscopy confirmed polymeric complexation, while scanning electron microscopy revealed a denser internal structure in APS microcapsules, consistent with their higher solution viscosity (433.7 ± 0.7 cP) compared to AS (101.3 ± 0.5 cP). Both encapsulation systems significantly enhanced bacterial survival in simulated gastric fluid (SGF, pH 2.0) over 2 h (p < 0.05). Free cells exhibited a dramatic decline from 9.62 ± 0.47 to 2.48 ± 0.16 Log CFU/g, whereas APS-encapsulated cells decreased only from 6.98 ± 0.06 to 4.35 ± 0.71 Log CFU/g, demonstrating the substantial acid-protective effect of the alginate-based matrices. In simulated intestinal conditions (PBS, pH 7.4), APS microcapsules showed a significantly superior release profile compared to AS (p < 0.05), with viable counts increasing from 6.38 ± 0.19 to 6.98 ± 0.06 Log CFU/g within 6 h, while AS capsules released cells more gradually (4.70 ± 0.24 to 6.72 ± 0.36 Log CFU/g). This enhanced pH-triggered release is attributed to the deprotonation and swelling of pectin chains at neutral pH, combined with their susceptibility to intestinal enzymatic degradation, enabling efficient payload discharge after gastric transit. By coupling robust acid resistance with rapid intestinal release, APS microcapsules provide a clear functional advantage for targeted probiotic delivery and represent a promising platform for the development of next-generation probiotic-enriched functional foods.

Keywords:  Alginate-pectin-starch hydrogel; Electrospray microencapsulation; Lactobacillus plantarum

DOI:  https://doi.org/10.1016/j.ijbiomac.2026.151757
Food Chem. 2026 Mar 23. pii: S0308-8146(26)01152-0. [Epub ahead of print]513 148994

Microencapsulation of probiotics using crosslinked lotus seed starch and alginate: protection and structural evolution during digestion.

Lanxin Li, Shuyi You, Xiangfu Jiang, Hongqiang Wu, Baodong Zheng, Hongliang Zeng, Yi Zhang.

  Probiotics are vulnerable to simulated gastrointestinal environments, necessitating effective encapsulation carriers. This study prepared microcapsules with low/medium/high-crosslinked lotus seed crosslinked resistant starch (LS-2/6/12CS) and sodium alginate (SA), evaluating their protection on Lactiplantibacillus plantarum ACCC 11095 and structural changes. Results indicated that the encapsulation rate increased with higher LSCS crosslinking degree. During digestion, the characteristic starch peak of LSCS weakens and the SA peak essentially disappears, while LSCS crystal structure remains unchanged, indicating the interaction between both LSCS and SA still existed. The protective effect of microcapsules was significantly better than that of the unencapsulated bacteria. The probiotics encapsulated in LC6/12-SA released over 106 CFU/g of viable bacteria after simulated gastrointestinal digestion, suggesting that could exert a probiotic effect in the intestinal tract. Therefore, LS-6/12CS-SA can be used as an effective oral probiotic carrier to protect the smooth arrival of probiotics in the gut and play a probiotic role.

Keywords:  In vitro digestion; Lotus seed cross-linked resistant starch; Microcapsules; Probiotics; Structural deconstruction

DOI:  https://doi.org/10.1016/j.foodchem.2026.148994
Gut Microbes Rep. 2026 ;3(1): 2622881

An artificial mucus-integrated in vitro model enables stable live probiotic-host co-culture and recapitulates dynamic hBD-2-mediated antimicrobial feedback.

Wenxin Cao, Yumiko Watanabe-Yasuoka, Toshihiro Sashihara, Masaki Nishikawa, Yasuyuki Sakai.

  In vitro models for host-microbe interaction often have limited physiological relevance due to the absence of a protective mucus layer, reliance on non-viable bacteria, and short co-culture durations. Here, we present the first scalable and biocompatible in vitro model integrating an artificial mucus barrier that enables stable 48-hour co-culture of live Lactiplantibacillus plantarum OLL2712 with Caco-2 cells at exposure ratios up to 1,000. This model maintained epithelial viability, supported bacterial proliferation, and enabled dynamic host responses. Notably, during co-culture, while hBD-2 gene expression was observed under both with-mucus and without-mucus conditions, protein secretion occurred only in the presence of mucus, reaching approximately a 100-fold higher level than previously reported. This finding underscores the essential role of the mucus barrier in preserving epithelial function and maintaining the downstream host response. The model recapitulates a complete host-microbe feedback loop involving microbial stimulation, antimicrobial peptide (hBD-2) secretion, and subsequent bacterial suppression, thereby linking epithelial defense activation to microbial regulation. It provides a reproducible, physiologically relevant, and animal-free platform for probiotic screening and mechanistic studies of mucus-associated intestinal disorders such as inflammatory bowel disease.

Keywords:  In vitro intestinal model; artificial mucus; host-microbe interaction; human β-defensin-2; probiotic screening

DOI:  https://doi.org/10.1080/29933935.2026.2622881
Regen Biomater. 2026 ;13 rbaf134

Engineered bilayer hydrogel with spatiotemporal drug and oxygen delivery for diabetic wound microenvironment reprogramming.

Huaping Li, Quan Chen, Bihua Liang, Huiyan Deng, Chao Bi, Liqian Peng, Jiaoquan Chen, Shanshan Ou, Luoyu Zhang, Ziyan Chen, Huilan Zhu.

  The impaired healing of diabetic wounds primarily stems from persistent inflammation, a hypoxic microenvironment, and heightened susceptibility to infection. However, most existing studies focus on simple functional stacking, rather than aligning with the dynamic pathological repair process, which hinders the maximization of therapeutic efficacy of the repair materials. In this study, an intelligently responsive, bilayer anti-fouling nanocomposite hydrogel (Ca@Q-E@SGH) was developed for spatiotemporally synergistic therapy via spatiotemporal drug and oxygen delivery strategies. Its core component (Ca@Q-E) consists of calcium peroxide encapsulated by phenylboronic acid-modified quaternary ammonium chitosan, with epigallocatechin gallate (EGCG) linked via boronate esters. This dynamic bond enables ROS/glucose-responsive EGCG release to reprogram macrophages from the M1 to M2 phenotype, mitigating early-stage inflammation. As the matrix degrades, sustained oxygen is released from CaO2, supporting vascularization during tissue remodeling. Furthermore, the bilayer hydrogel structure is designed to provide multiple protective functions: the lower layer rapidly crosslinks to encapsulate the functional nanoparticles, while the upper layer forms a highly hydrophilic anti-fouling coating that effectively prevents pathogen adhesion. Collectively, this integrated platform combines intelligent microenvironment-responsive drug release for antibacterial and anti-inflammatory effects, followed by sequential oxygen delivery aligned with the wound healing stages, along with physical anti-fouling protection. As a result, the treated wounds achieved a remarkable closure rate of 99.1% by day 14. This study presents a comprehensive strategy for diabetic wound management by seamlessly integrating smart anti-inflammatory action, prolonged oxygen supply, and efficient anti-fouling capacity into a single coordinated platform.

Keywords:  anti-fouling; anti-inflammatory; boronic ester bond; diabetic wound healing; oxygen release

DOI:  https://doi.org/10.1093/rb/rbaf134
Anal Sci. 2026 Mar 31.

Optical analysis of bacterial metabolic activity and spore germination via formazan formation.

Hikaru Ikeda, Miya Kawanaka, Koki Takenaga, Akira Tokonami, Kanta Sako, Satohiro Itagaki, Shigeki Nishii, Hiroshi Shiigi.

  Despite improved sanitation protocols, foodborne illnesses caused by spore-forming bacteria remain a persistent concern. In this study, we developed a method to visualize bacterial metabolic activity via dark-field microscopy by exploiting the optical properties of formazan particles generated from the reduction of the tetrazolium salt 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) by intracellular cofactors. Escherichia coli was used as a model organism to track formazan formation, which became pronounced following cell division, showing a strong correlation with metabolic activity. The method was further applied to various bacterial species with diverse respiratory and fermentation characteristics to evaluate the influence of metabolic profiles on formazan formation. Moreover, Bacillus subtilis spores were employed to investigate metabolic changes during germination and outgrowth. Time-lapse imaging revealed stage-specific formazan production, demonstrating the potential of this technique to monitor the metabolic reactivation process non-destructively. These findings suggest that MTT-based optical monitoring can serve as a valuable tool for assessing bacterial viability and spore germination dynamics, with potential applications in food safety and microbial risk control.

Keywords:  Dark-field microscopy; MTT assay; Metabolic activity; Reduced coenzymes; Spore-forming bacteria

DOI:  https://doi.org/10.1007/s44211-026-00891-4