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Toxic oxyanions of Cr(VI) can be potentially removed by adsorbents with positively charged surfaces. In this study, we synthesized a stable and insoluble amine-rich polymer composite (CS–PEI–GLA) by crosslinking polyethyleneimine (PEI), a soluble amine-rich synthetic polymer, and chitosan (CS) with glutaraldehyde (GLA). The positively charged amine groups were the main adsorption sites. The batch investigation demonstrated that the adsorbent was able to remove ≥90% of chromium at pH ranging from 2 to 8. Due to deprotonation of the amine groups, chromium removal decreased at higher pH values. The adsorption was fast and reached equilibrium after 45 min. The maximum adsorption capacity was 500 mg g−1 according to the Langmuir isotherm and did not decrease in the presence of monovalent anions. In the column study, the adsorption capacity was the highest when the flow rate was the lowest (5 mL min−1), influent concentration was medium (225 mg L−1), and the bed height was the shortest (3.5 cm). NaOH was the best recovery reagent with recovery of 67% in batch and 31% in the column. The CS–PEI–GLA composite was able to remove 97.1 ± 0.1% chromium in batch and treat 750 mL of electroplating wastewater with a 3.5 cm packed-bed column. 

Ischemic heart injury causes permanent cardiomyocyte loss and fibrosis impairing cardiac function. Tissue derived biomaterials have shown promise as an injectable treatment for the post‐ischemic heart. Specifically, decellularized extracellular matrix (dECM) is a protein rich suspension that forms a therapeutic hydrogel once injected and improves the heart post‐injury response in rodents and pig models. Current dECM‐derived biomaterials are delivered to the heart as a liquid dECM hydrogel precursor or colloidal suspension, which gels over several minutes. To increase the functionality of the dECM therapy, an injectable solid dECM microparticle formulation derived from heart tissue to control sizing and extend stability in aqueous conditions is developed. When delivered into the infarcted mouse heart, these dECM microparticles protect cardiac function promote vessel density and reduce left ventricular remodeling by sustained delivery of biomolecules. Longer retention, higher stiffness, and slower protein release of dECM microparticles are noted compared to liquid dECM hydrogel precursor. In addition, the dECM microparticle can be developed as a platform for macromolecule delivery. Together, the results suggest that dECM microparticles can be developed as a modular therapy for heart injury.

 

Precision medicine requires high throughput cell isolation and measurement that maintains physiology. Unfortunately, many techniques are slow or alter cell biomarkers cells. This necessitates new approaches, which we achieve by integrating affinity‐based cell isolation with spiral microfluidics. We characterize the device via computational simulations, predicting wall shear stress within an order of magnitude of arterial wall shear stress (~0.2 Pa). We identify that poly‐l‐lysine supplementation preserves cell geometry and improves cell release. We demonstrate preservation of angiogenic biomarker concentrations, measuring 1,000–2,000 vascular endothelial growth factor receptor‐1 per human umbilical vein endothelial cell, which is in line with the previously reported measurements. We attain 76.7 ± 9.0% release of captured cells by integrating thermophoresis and optimizing buffer residence time. Ultimately, we find that combining affinity‐based cell isolation (secondary anchor targeted cell release) with spiral microfluidics offers a fast, biomarker preserving approach needed to individualize medicine.