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Current therapies for the devastating damage caused by traumatic brain injuries (TBI) are limited. This is in part due to poor drug efficacy to modulate neuroinflammation, angiogenesis and/or promoting neuroprotection and is the combined result of challenges in getting drugs across the blood brain barrier, in a targeted approach. The negative impact of the injured extracellular matrix (ECM) has been identified as a factor in restricting post‐injury plasticity of residual neurons and is shown to reduce the functional integration of grafted cells. Therefore, new strategies are needed to manipulate the extracellular environment at the subacute phase to enhance brain regeneration. In this review, potential strategies are to be discussed for the treatment of TBI by using self‐assembling peptide (SAP) hydrogels, fabricated via the rational design of supramolecular peptide scaffolds, as an artificial ECM which under the appropriate conditions yields a supramolecular hydrogel. Sequence selection of the peptides allows the tuning of these hydrogels' physical and biochemical properties such as charge, hydrophobicity, cell adhesiveness, stiffness, factor presentation, degradation profile and responsiveness to (external) stimuli. This review aims to facilitate the development of more intelligent biomaterials in the future to satisfy the parameters, requirements, and opportunities for the effective treatment of TBI. [ABSTRACT FROM AUTHOR]

The nondestructive localization and traceability of polymers by fluorescent tagging has become a valuable tool for biomedical applications. Integration of fluorescent molecule to the pristine polymers could modify polymers' degradation rate which is still unpredictable from a scaffold application standpoint. The current study focused to understand the material perspective of fluorescently tagged biodegradable polymers such as polycaprolactone (PCL) and poly (d,l‐lactide‐co‐glycolide) (PLGA) with fluorescein amine isomer I (FITC). PCL‐FITC and PLGA‐FITC were characterized using FTIR for surface chemistry analysis and rheology for their mechanical properties. The grafted materials were utilized to form 3‐dimentional scaffolds, and their degradation was monitored under accelerated degradation conditions triggered by pH. It was found that PCL and PCL‐FITC had a very slow degradation rate, when compared to PLGA and PLGA‐FITC. Both the FITC tagged materials displayed a faster degradation rate compared to their respective pristine material. Biocompatibility of the FITC conjugated polymers was tested using human‐adipose derived stem cells (hADSCs) revealing that the sub products from the degradation of the polymers over 7 days did not negatively affect the cellular metabolic activity. This work highlights the significance of initial characterization of fluorescent modified polymers for future biomedical application. [ABSTRACT FROM AUTHOR]

The directed differentiation of human pluripotent stem cells (hPSCs) into defined populations has advanced regenerative medicine, especially for Parkinson's disease where clinical trials are underway. Despite this, tumorigenic risks associated with incompletely patterned and/or quiescent proliferative cells within grafts remain. Addressing this, donor stem cells carrying the suicide gene, thymidine kinase (activated by the prodrug ganciclovir, GCV), are employed to enable the programmed ablation of proliferative cells within neural grafts. However, coinciding the short half‐life of GCV with the short S‐phase of neural progenitors is a key challenge. To overcome this, a smart hydrogel delivery matrix is fabricatedto prolong GCV presentation. Following matrix embedment, GCV retains its functionality, demonstrated by ablation of hPSCs and proliferating neural progenitors in vitro. A prolonged GCV release is measured by mass spectrometry following the injection of a GCV‐functionalized hydrogel into mouse brains. Compared to suboptimal, daily systemic GCV injections, the intracerebral delivery of the functionalized hydrogel, as a "one‐off treatment", reduce proliferative cells in both hPSC‐derived teratomas and neural grafts, without affecting the graft's functional unit (i.e., neurons). It is demonstrated that a functionalized biomaterial can enhance prodrug delivery and address safety concerns associated with the use of hPSCs for brain repair. [ABSTRACT FROM AUTHOR]