Untethered Microgrippers for Biopsy in the Upper Urinary Tract.

Untethered microrobots offer the possibility to perform medical interventions in anatomically complex and small regions in the body. Presently, it is necessary to access the upper urinary tract to diagnose and treat Upper Tract Urothelial Carcinoma (UTUC). Diagnostic and treatment challenges include ensuring adequate tissue sampling, accurately grading the disease, achieving completeness in endoscopic treatment, and consistently delivering medications to targeted sites.

Untethered shape-changing devices in the gastrointestinal tract.

Introduction: Advances in microfabrication, automation, and computer engineering seek to revolutionize small-scale devices and machines. Emerging trends in medicine point to smart devices that emulate the motility, biosensing abilities, and intelligence of cells and pathogens that inhabit the human body. Two important characteristics of smart medical devices are the capability to be deployed in small conduits, which necessitates being untethered, and the capacity to perform mechanized functions, which requires autonomous shape-changing.

Autonomous Untethered Microinjectors for Gastrointestinal Delivery of Insulin.

The delivery of macromolecular drugs the gastrointestinal (GI) tract is challenging as these drugs display low stability as well as poor absorption across the intestinal epithelium. While permeation-enhancing drug delivery methods can increase the bioavailability of low molecular weight drugs, the effective delivery of high molecular weight drugs across the tight epithelial cell junctions remains a formidable challenge. Here, we describe autonomous microinjectors that are deployed in the GI tract, then efficiently penetrate the GI mucosa to deliver a macromolecular drug, insulin, to the systemic circulation.

Preparation of lignosulfonate-based nanofiltration membranes with improved water desalination performance.

Pulping and papermaking generate large amounts of waste in the form of lignosulfonates which have limited valorized applications so far. Herein, we report a novel lignosulfonate-based nanofiltration membrane, prepared by using polyethylenimine (PEI) and sodium lignosulfonate (SL) via a layer-by-layer (LbL) self-assembly. As a low-cost and renewable natural polyelectrolyte, SL is selected to replace the synthetic polyelectrolyte commonly used in the conventional LbL fabrication for composite membranes.

Gastrointestinal-resident, shape-changing microdevices extend drug release in vivo.

Extended-release gastrointestinal (GI) luminal delivery substantially increases the ease of administration of drugs and consequently the adherence to therapeutic regimens. However, because of clearance by intrinsic GI motility, device gastroretention and extended drug release over a prolonged duration are very challenging. Here, we report that GI parasite-inspired active mechanochemical therapeutic grippers, or theragrippers, can reside within the GI tract of live animals for 24 hours by autonomously latching onto the mucosal tissue.

3D Printing of an Grown MOF Hydrogel with Tunable Mechanical Properties.

Due to their precisely modifiable microporosity and chemical functionality, Metal-Organic Frameworks (MOFs) have revolutionized catalysis, separations, gas storage, drug delivery, and sensors. However, because of their rigid and brittle powder morphology, it is challenging to build customizable MOF shapes with tunable mechanical properties. Here, we describe a new three-dimensional (3D) printing approach to create stretchable and tough MOF hydrogel structures with tunable mechanical properties.

Extraction of Polysaccharide from Lindl. by Subcritical Water Extraction.

Subcritical water extraction (SWE) uses hot compressed water as an effective solvent for both polar and nonpolar compounds and has been developed as an environmentally benign extraction technology for natural materials. Polysaccharides as one of the main ingredients in plants showed obvious biological activity. Thus, SWE of polysaccharides obtained from Lindl.

Dual-Gel 4D Printing of Bioinspired Tubes.

The distribution of periodic patterns of materials with radial or bilateral symmetry is a universal natural design principle. Among the many biological forms, tubular shapes are a common motif in many organisms, and they are also important for bioimplants and soft robots. However, the simple design principle of strategic placement of 3D printed segments of swelling and nonswelling materials to achieve widely different functionalities is yet to be demonstrated.