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Flexible bioelectronic devices have attracted immense interest in the biomedical field because of their wearability, biocompatibility, diverse functionalities, and ease of personalization. Recently, flexible energy harvesters have been developed, and attempts have been made to integrate them with such devices, enabling them to operate without external batteries or power supply. In this review, the latest advances in flexible energy harvesters and their use in wearable devices are discussed. Energy harvesters for versatile biomedical applications are summarized. Finally, the challenges and future perspectives of self‐powered biomedical systems that enable wearable healthcare monitoring and management are outlined. [ABSTRACT FROM AUTHOR]

Hepatocellular carcinoma (HCC) is a malignant and deadly form of liver cancer with limited treatment options. Transcatheter arterial chemoembolization, a procedure that delivers embolic and chemotherapeutic agents through blood vessels, is a promising cancer treatment strategy. However, it still faces limitations, such as inefficient agent delivery and the inability to address tumor‐induced immunosuppression. Here, a drug‐eluting shear‐thinning hydrogel (DESTH) loaded with chemotherapeutic and immunotherapeutic agents in nanocomposite hydrogels composed of gelatin and nanoclays is presented as a therapeutic strategy for a catheter‐based endovascular anticancer approach. DESTH is manually deliverable using a conventional needle and catheter. In addition, drug release studies show a sustained and pH‐dependent co‐delivery of the chemotherapy doxorubicin (acidic pH) and the immune‐checkpoint inhibitor aPD‐1 (neutral pH). In a mouse liver tumor model, the DESTH‐based chemo/immunotherapy combination has the highest survival rate and smallest residual tumor size. Finally, immunofluorescence analysis confirms that DESTH application enhances cell death and increases intratumoral infiltration of cytotoxic T‐cells. In conclusion, the results show that DESTH, which enables efficient ischemic tumor cell death and effective co‐delivery of chemo‐ and immunotherapeutic agents, may have the potential to be an effective therapeutic modality in the treatment of HCC. [ABSTRACT FROM AUTHOR]

Stimuli-responsive peptide gels are a growing class of functional biomaterials that are involved in many applications in research. Here, we present a novel di-peptide hydrogel from the compound Boc--Phe--Trp--OH in various buffer and pH conditions. We examine the effects of different stimuli, including temperature and pH, on the mechanical strength of the gels through frequency rheology studies. We found that this hydrogelator is highly pH dependent, only forming a gel in a narrow range of pH 6-7. This hydrogelator hold promise for the development of new stimuli-responsive biomaterials for specific applications that require this type of specific stimuli. Key words: hydrogel, peptides, stimuli responsive, pH-dependent gelation, rheology. Les gels peptidiques stimulables constituent une classe grandissante de biomateriaux fonctionnels mis a contribution dans de nombreuses applications en recherche. Dans le present article, nous faisons etat d'un nouvel hydrogel dipeptidique produit a partir du compose Boc--Phe--Trp--OH dans divers tampons et conditions de pH. Nous examinons les effets de differents stimuli, tels que la temperature et le pH, sur la resistance mecanique des gels au moyen d'etudes de rheologie frequentielle. Nos resultats ont montre que ce gelifiant est tres sensible au pH, formant un hydrogel dans un intervalle de pH etroit (pH 6-7). Ce gelifiant constitue une avenue prometteuse pour la mise au point de nouveaux biomateriaux stimulables destines a des applications particulieres necessitant ce type de stimuli tres precis. [Traduit par la Redaction] Mots-cles : hydrogel, peptides, stimulable, gelification sensible au pH, rheologie., Introduction Peptide-based supramolecular gels are functional materials that have been the subject of research due to their versatility and their wide range of applications in many fields. (1) They can [...]

Supramolecular amino acid and peptide hydrogels are functional materials with a wide range of applications, however, their ability to serve as matrices for enzyme entrapment have been rarely explored. Two amino acid conjugates were synthesized and explored for hydrogel formation. These hydrogels were characterized in terms of strength and morphology, and their ability to entrap enzymes while keeping them active and reusable was explored. It was found that the hydrogels were able to successfully entrap two common and significant enzymes—horseradish peroxidase and α-amylase—thus keeping them active and stable, along with inducing recycling capabilities, which has potential to further advance the industrial biotransformation field. [ABSTRACT FROM AUTHOR]

Supramolecular gels are a fascinating class of soft materials that have attracted significant attention in recent years. They are composed of small molecule gelators that assemble into supramolecular network structures. The resulting space is filled with solvent. Some gel materials are able to respond to various stimuli making them attractive drug delivery vehicles and as matrices for tissue regeneration. Peptide-based gel materials are particularly attractive as they possess numerous advantages including biocompatibility and biodegradability. Stimuli-responsive peptides that alter properties as a function of pH, redox, temperature, and enzymes offer the potential to create materials with tunable characteristics. In addition, the ability of metal ions to improve the strength of gelation or act as a scaffold has become an interesting approach to develop dynamic peptide gel materials. In this review, the stimuli-responsive properties (pH, redox, temperature, and enzyme responsive properties), as well as the biocompatible/-degradable nature of the peptide gelators are highlighted. In addition, metal ions are discussed as a stimulus to enhance peptide gelation and a number of potential applications of these peptide gelators are provided with an outlook on future directions., (© 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)