Publications by authors named "Benjamin M Geilich"

mRNA vaccines have the potential to tackle many unmet medical needs that are unable to be addressed with conventional vaccine technologies. A potent and well-tolerated delivery technology is integral to fully realizing the potential of mRNA vaccines. Pre-clinical and clinical studies have demonstrated that mRNA delivered intramuscularly (IM) with first-generation lipid nanoparticles (LNPs) generates robust immune responses.

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Hydrogel-based biomaterials have been widely used for tissue engineering applications because of their high water content, swellability, and permeability, which facilitate transport and diffusion of essential nutrients, oxygen, and waste across the scaffold. These characteristics make hydrogels suitable for encapsulating cells and creating a cell supportive environment that promotes tissue regeneration when implanted in vivo. This is particularly important in the context of tissues whose intrinsic regenerative capacity is limited, such as cartilage.

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In recent years, an increasing body of research has indicated that the antimicrobial activity of certain antibiotic drugs can be enhanced by the addition of specific metabolites. This study aimed to incorporate these findings into polymersomes (novel polymer-based nanoscale drug delivery vehicles) which can be loaded with various therapeutic molecules and nanoparticles. Polymersome technology has shown promising results in treating antibiotic-resistant infections by co-encapsulating the antibiotic methicillin with silver nanoparticles.

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Traditional cancer treatments contain several limitations such as incomplete ablation and multidrug resistance. It is known that photodynamic therapy (PDT) is an effective treatment for several tumor types especially melanoma cells. During the PDT process, protoporphyrin IX (PpIX), an effective photosensitizer, can selectively kill cancer cells by activating a special light source.

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Here, the antibacterial activity of dextran-coated nanoceria was examined against Pseudomonas aeruginosa and Staphylococcus epidermidis by varying the dose, the time of treatment, and the pH of the solution. Findings suggested that dextran-coated nanoceria particles were much more effective at killing P. aeruginosa and S.

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The rising prevalence and severity of antibiotic-resistant biofilm infections poses an alarming threat to public health worldwide. Here, biocompatible multi-compartment nanocarriers were synthesized to contain both hydrophobic superparamagnetic iron oxide nanoparticles (SPIONs) and the hydrophilic antibiotic methicillin for the treatment of medical device-associated infections. SPION co-encapsulation was found to confer unique properties, enhancing both nanocarrier relaxivity and magneticity compared to individual SPIONs.

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Encapsulating bacteria within constrained microenvironments can promote the manifestation of specialized behaviors. Using double-emulsion droplet-generating microfluidic synthesis, live Bacillus subtilis bacteria were encapsulated in a semi-permeable membrane composed of poly(ethylene glycol)-b-poly(D,L-lactic acid) (mPEG-PDLLA). This polymer membrane was sufficiently permeable to permit exponential bacterial growth, metabolite-induced gene expression, and rapid biofilm growth.

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The chemotherapy for tuberculosis (TB) is complicated by its long-term treatment, its frequent drug dosing, and the adverse effects of anti-TB drugs. In this study, we have developed two nanocomposites (A and B) by intercalating the anti-TB drug isoniazid (INH) into Zn/Al-layered double hydroxides. The average size of the nanocomposites was found to bê164 nm.

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β-type Ti alloys containing Nb are exciting materials for numerous orthopedic and dental applications due to their exceptional mechanical properties. To improve their cytocompatibility properties (such as increasing bone growth and decreasing infection), the surfaces of such materials can be optimized by adding elements and/or nanotexturing through anodization. Because of the increasing prevalence of orthopedic implant infections, the objective of this in vitro study was to add Sn and create unique nanoscale surface features on β-type Ti alloys.

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Magnetic nanoparticles (MNPs) were synthesized by the coprecipitation of Fe(2+) and Fe(3+) iron salts in alkali media. MNPs were coated by chitosan (CS) to produce CS-MNPs. Streptomycin (Strep) was loaded onto the surface of CS-MNPs to form a Strep-CS-MNP nanocomposite.

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The rapidly diminishing number of effective antibiotics that can be used to treat infectious diseases and associated complications in a physician's arsenal is having a drastic impact on human health today. This study explored the development and optimization of a polymersome nanocarrier formed from a biodegradable diblock copolymer to overcome bacterial antibiotic resistance. Here, polymersomes were synthesized containing silver nanoparticles embedded in the hydrophobic compartment, and ampicillin in the hydrophilic compartment.

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While there have been numerous studies to determine osteoblast (bone forming cell) functions on nanocrystalline compared to micron crystalline ceramics, there have been few studies which have examined osteoclast activity (including tartrate-resistant acid phosphatase, formation of resorption pits, size of resorption pits, and receptor activator of nuclear factor κB [RANK]). This is despite the fact that osteoclasts are an important part of maintaining healthy bone since they resorb bone during the bone remodeling process. Moreover, while it is now well documented that bone formation is enhanced on nanoceramics compared to micron ceramics, some have pondered whether osteoblast functions (such as osteoprotegerin and RANK ligand [RANKL]) are normal (ie, non-diseased) on such materials compared to natural bone.

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The primary challenge in finding a treatment for tuberculosis (TB) is patient non-compliance to treatment due to long treatment duration, high dosing frequency, and adverse effects of anti-TB drugs. This study reports on the development of a nanodelivery system that intercalates the anti-TB drug isoniazid into Mg/Al layered double hydroxides (LDHs). Isoniazid was found to be released in a sustained manner from the novel nanodelivery system in humans in simulated phosphate buffer solutions at pH 4.

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Because of their magnetic properties, magnetic nanoparticles (MNPs) have numerous diverse biomedical applications. In addition, because of their ability to penetrate bacteria and biofilms, nanoantimicrobial agents have become increasingly popular for the control of infectious diseases. Here, MNPs were prepared through an iron salt coprecipitation method in an alkaline medium, followed by a chitosan coating step (CS-coated MNPs); finally, the MNPs were loaded with ampicillin (amp) to form an amp-CS-MNP nanocomposite.

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The treatment of tuberculosis by chemotherapy is complicated due to multiple drug prescriptions, long treatment duration, and adverse side effects. We report here for the first time an in vitro therapeutic effect of nanocomposites based on para-aminosalicylic acid with zinc layered hydroxide (PAS-ZLH) and zinc-aluminum layered double hydroxides (PAS-Zn/Al LDH), against mycobacteria, Gram-positive bacteria, and Gram-negative bacteria. The nanocomposites demonstrated good antimycobacterial activity and were found to be effective in killing Gram-positive and Gram-negative bacteria.

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There has been a significant and growing concern over nosocomial medical device infections. Previous studies have demonstrated that embedding nanoparticles alone (specifically, zinc oxide [ZnO]) in conventional polymers (eg, polyvinyl chloride [PVC]) can decrease bacteria growth and may have the potential to prevent or disrupt bacterial processes that lead to infection. However, little to no studies have been conducted to determine mammalian cell functions on such a nanocomposite material.

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In hospitals and clinics worldwide, medical device surfaces have become a rapidly growing source of nosocomial infections. In particular, patients requiring mechanical ventilation (and, thus, intubation with an endotracheal tube) for extended lengths of time are faced with a high probability of contracting ventilator-associated pneumonia. Once inserted into the body, the endotracheal tube provides a surface to which bacteria can adhere and form a biofilm (a robust, sticky matrix that provides protection against the host immune system and antibiotic treatment).

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