Portable, wearable and implantable artificial kidney systems: needs, opportunities and challenges.

Haemodialysis is life sustaining but expensive, provides limited removal of uraemic solutes, is associated with poor patient quality of life and has a large carbon footprint. Innovative dialysis technologies such as portable, wearable and implantable artificial kidney systems are being developed with the aim of addressing these issues and improving patient care. An important challenge for these technologies is the need for continuous regeneration of a small volume of dialysate. Dialysate recycling systems based on sorbents have great potential for such regeneration. Novel dialysis membranes composed of polymeric or inorganic materials are being developed to improve the removal of a broad range of uraemic toxins, with low levels of membrane fouling compared with currently available synthetic membranes. To achieve more complete therapy and provide important biological functions, these novel membranes could be combined with bioartificial kidneys, which consist of artificial membranes combined with kidney cells. Implementation of these systems will require robust cell sourcing; cell culture facilities annexed to dialysis centres; large-scale, low-cost production; and quality control measures. These challenges are not trivial, and global initiatives involving all relevant stakeholders, including academics, industrialists, medical professionals and patients with kidney disease, are required to achieve important technological breakthroughs.

Design of new hydrolyzed collagen-modified magnetic nanoparticles to capture pathogens.

Enrichment and diagnosis tools for pathogens currently available are time consuming, thus the development of fast and highly sensitive alternatives is desirable. In this study, a novel approach was described that enables selective capture of bacteria expressing hydrolyzed collagen-binding adhesins with hydrolyzed collagen-coated magnetic nanoparticles (MNPs). This platform could be useful to shorten the time needed to confirm the presence of a bacterial infection. MNPs were synthesized by a simple two-step approach through a green co-precipitation method using water as solvent. These MNPs were specifically designed to interact with pathogenic bacteria by establishing a hydrolyzed collagen-adhesin linker. The bacterial capture efficacy of hydrolyzed collagen MNPs (H-Coll@MNPs) for bacteria expressing collagen binding adhesins was 1.3 times higher than that of arginine MNPs (Arg@MNPs), herein used as control. More importantly, after optimization of the MNP concentration and contact time, the H-Coll@MNPs were able to capture 95% of bacteria present in the samples. More importantly, the bacteria can be enriched within 30 min and the time for bacterial identification is effectively shortened in comparison to the "gold standard" in clinical diagnosis. These results suggest that H-Coll@MNPs can be used for the selective isolation of specific bacteria from mixed populations present, for example, in biological samples.