Bacterial biofilms associated with orthopedic implants are notorious cell associations of pathogens that show resistance against antibiotic medications and the host immune response. The presence of hard-to-penetrate extracellular polymeric substances in the biofilm provides a protective shield against the different modes of action of conventional antimicrobial agents. To address the severe complications associated with biofilm-related infections in medical implants such as prosthetic joint infections (PJIs), we have developed a treatment approach that is based on a thermoresponsive hydrogel nanocomposite system, containing Damino acids (D-AAs) and engineered gold nanorods (AuNRs), which can undergo sol-to-gel transformation at physiological temperatures for site-specific sustained drug release. Our two-step approach that utilizes a light-actuated AuNR hydrogel composite system for a combination of photothermal treatment (PTT), following initial biofilm disruption with D-AAs, is filling a current gap to develop alternative therapies that have the potential to advance a whole range of PJI medical treatment technologies. Using this two-step approach, we were able to successfully demonstrate in vitro the effective disruption and total eradication of Staphylococcus aureus biofilms formed on different metal alloys (Ti-based, CoCr, and Ta-based alloys) used in the manufacture of prosthetic joints. Moreover, this nanocomposite treatment is safe, does not lead to thermal damage of the surrounding soft tissues, and is localized to the disruption of the biofilms on the surface of the metal alloys. This treatment modality, when adapted to an open surgical approach that is compatible to current irrigation and debridement (I&D) medical procedures, has great potential to combat chronic PJIs and may help to preserve the implant, thereby decreasing the morbidity and mortality of the alternative revision surgery procedures.

Magnetic particle spectrometry offers a reliable and facile approach for the screening of promising nanoengineered fertilizers.

Pediatric implants are a special subclass of a vast number of clinically used medical implants, uniquely designed to address the needs of young patients who are at the onset of their developmental growth stage. Given the vulnerability of the implant receiver, it is crucial that the implants manufactured for small children with birth-associated defects be given careful considerations and great attention to design detail to avoid postoperative complications. In this review, we focus on the most common types of medical implants manufactured for the treatment of birth defects originating from both genetic and environmental causes. Particular emphasis is devoted toward identifying the implant material of choice and manufacturing approaches for the fabrication of pediatric prostheses. Along this line, the emerging role of 3D printing to enable customized implants for infants with congenital disorders is presented, as well as the possible complications associated with prosthetic-related infections that is prevalent in using artificial implants for the treatment of birth malformations.

The effect of nanostructuring on the electrochemical activity of a series of Au/Ag electrocatalysts, with and without graphene nanoplatelets (G) as carbon matrix support and β-cyclodextrin as capping agent, was systematically investigated using the ferri/ferrocyanide redox probe. A series of Au/Ag nanostructures with different morphologies were synthesized and characterized using a combination of spectroscopy, electron microscopy, and electroanalytical methods. Evaluation of the cyclic voltammograms obtained from the ferri/ferrocyanide redox probe using electrodes modified with the different Au/Ag nanostructures revealed significant enhancement in peak currents upon using hollow Au/Ag nanobox and porous-hollow Au/Ag nanocage analogs in comparison to conventional solid spherical Au nanoparticles. The observed improvements in electrochemical activities can be attributed to the nanoreactor cage and edge effects in the hollow cubic nanostructures. Moreover, the dispersion of the nanostructures in G and their surface modification with β-cyclodextrin further enhanced their electrochemical performance. The best performing Au/Ag nanostructure that was modified with β-cyclodextrin and G was used to fabricate an electrochemical sensor for the stress biomarker cortisol. The resulting electrochemical sensor exhibited good linear response to cortisol in the concentration range of 1 pM to 100 nM, making it a promising platform technology for monitoring the physiological stress indicator. Nanoparticle based electrochemical sensors have received considerable attention in recent years due to their exceptional attributes including high sensitivity, good reliability, and stability.1-4 Moreover, engineered electrocatalytic nanomaterials provide a means to develop simple-to-contruct 5 electrochemical sensors that can be used for routine point-of-care health monitoring and diagnostics.6,7 However, for most biomedical applications, a next generation sensor platform technology will require significant improvements in the nanomaterials' properties to facilitate lower detection limits and higher sensitivities under lower costs for mass production. 8,9 An effective electrochemical sensor relies heavily on the surface architecture of the working electrode in order to allow the recognition process to occur under short response time, achieve good signal-tonoise (S/N) ratio, and detect the analyte of interest at low limits of detection (LOD) with high selectively.9-11 For these purposes, Au nanoparticles have been heavily explored for their use as modifiers of the electrochemical sensor's interface due to their unique attributes such as high conductivity, 12 stability, 13 ease of enabling surface chemical modifications, 13,14 and their large surface-to-volume ratios. 15,16Moreover, Au nanoparticles are less susceptible to suffer from surface poisoning compared to other commonly used electrocatalytic nanometals. 17 Due to the many promising attributes of Au-based nanostructures, this nanomaterial has become a good scaffold for different electr...