Comparison of submerged and unsubmerged printing of ovarian cancer cells.

A high-throughput cell based assay would greatly aid in the development and screening of ovarian cancer drug candidates. Previously, a three-dimensional microfluidic printer that is not only capable of controlling the location of cell deposition, but also of maintaining a liquid, nutrient rich environment to preserve cellular phenotype has been developed (Wasatch Microfluidics). In this study, we investigated the impact (i.

Optimal tube length for the submerged printing of ovarian cancer cells.

Ovarian cancer is the fifth most common cancer affecting US women, killing more women each year than all other gynecologic cancers combined. Treatment of ovarian cancer is challenging with an overall 5-year survival rates of only 28-46% based on the metastatic state of the disease. While overall survival has improved with modern chemotherapy, poor outcomes have persisted.

Polymer-controlled extended combination release of silver and chlorhexidine from a bone void filler.

Although rates of total joint prosthetic infections remain relatively constant at 1-3%, an increasing number of orthopedic procedures and a corresponding rise in the absolute number of infectious complications mandate distinctly new solutions. In order to combat the implant infection threat, an antibiotic-releasing bone void filler (BVF), commercial tradename, ElutiBone™, has been developed using a combination of commercially available ceramic-based BVF plus clinically familiar biocompatible polymers, and a variety of select, dispersed antibiotics. While several traditional antibiotics have been successfully released for an extended duration, a more versatile strategy, releasing multiple antibiotics simultaneously, may be possible.

The submerged printing of cells onto a modified surface using a continuous flow microspotter.

The printing of cells for microarray applications possesses significant challenges including the problem of maintaining physiologically relevant cell phenotype after printing, poor organization and distribution of desired cells, and the inability to deliver drugs and/or nutrients to targeted areas in the array. Our 3D microfluidic printing technology is uniquely capable of sealing and printing arrays of cells onto submerged surfaces in an automated and multiplexed manner. The design of the microfluidic cell array (MFCA) 3D fluidics enables the printhead tip to be lowered into a liquid-filled well or dish and compressed against a surface to form a seal.

Molded polymer-coated composite bone void filler improves tobramycin controlled release kinetics.

Infection remains a significant problem associated with biomedical implants and orthopedic surgeries, especially in revision total joint replacements. Recent advances in antibiotic-releasing bone void fillers (BVF) provide new opportunities to address these types of device-related orthopedic infections that often lead to substantial economic burdens and reduced quality of life. We report improvements made in fabrication and scalability of an antibiotic-releasing polycaprolactone-calcium carbonate/phosphate ceramic composite BVF using a new solvent-free, molten-cast fabrication process.

Polymer-controlled release of tobramycin from bone graft void filler.

Despite clinical, material, and pharmaceutical advances, infection remains a major obstacle in total joint revision surgery. Successful solutions must extend beyond bulk biomaterial and device modifications, integrating locally delivered pharmaceuticals and physiological cues at the implant site, or within large bone defects with prominent avascular spaces. One approach involves coating clinically familiar allograft bone with an antibiotic-releasing rate-controlling polymer membrane for use as a matrix for local drug release in bone.

Scanning electron image analysis to monitor of implant degradation and host healing following implantation of a drug-eluting bone graft void filler - biomed 2013.

Osteomyelitis is most commonly caused by Staphylococcus aureus and often sourced during orthopedic surgical intervention. Successful treatment or prevention of this bone penetrating infection requires antibiotics be delivered in excess of the minimal inhibitory concentration to prohibit the growth of the causative organism for sufficient duration. Unfortunately, current standard-of-care antibiotic therapies, administered via intravenous or oral delivery, suffer not only from systemic toxicity and low patient compliance but also provide insufficient local concentrations for therapy.

Evaluating antibiotic release profiles as a function of polymer coating formulation - biomed 2011.

To address persistent 1-3% infection rates associated with orthopedic implant surgeries, the next generation of bone graft filler materials will no longer pharmacologically silent being endowed as a local drug delivery vehicle to maintain locally high levels of antibiotic. Bone allograft material, used as a structural support to fill the avascular spaces in bone defects, revision surgeries, and traumatic injury, can be used as a drug depot to provide effective antibiotic delivery over the orthopedically relevant six-to-eight week time period. Passive antibiotic coatings, applied in the surgical theater, are quickly depleted from the site, inadvertently promoting the development of drug-resistance.

A robust method to coat allograft bone with a drug-releasing polymer shell - biomed 2010.

Bone allograft material used for osseous void filling and structural support in skeletal reconstructive surgeries can also be used in combination as a drug carrier. Previous coating methods to load drugs, such as antibiotics and anti-inflammatories, provided an initial burst release, which may not be optimal for combating persistent local implant-associated bacterial infections. Theoretical drug release kinetics can be optimized not only with a clinically relevant drug-to-polymer ratio but also with a robust, effective rate-limiting release coating method.