Spray drying is one of the leading manufacturing methods for active pharmaceutical ingredients (APIs) owing to its rapid, single-step, and cost-effective nature. It also has the capacity to generate microspheres capable of controlled release of APIs including biomolecules and vaccines. However, one of the key challenges of spray-dried formulations especially with poly(lactic--glycolic acid) (PLGA)-based controlled-release injectables is burst release, where a significant fraction of the API is released prematurely within a short period of time following administration, leading to detrimental impact on the performance and quality of end products.
View Article and Find Full Text PDFCervical spondylotic myelopathy (CSM) is a progressive degenerative condition of the cervical spine and the most common cause of spinal cord injury in adults >55 years of age. Degenerative changes in the spine lead to spinal cord compression, resulting in symptoms such as gait instability, loss of dexterity in the hands, weakness, and sensory deficits. Diagnosis is delayed by 2,2-6,3 years and includes clinical examination and imaging such as MRI.
View Article and Find Full Text PDFNanoparticle (NP) formulations are inherently polydisperse making their structural characterization and justification of specifications complex. It is essential, however, to gain an understanding of the physico-chemical properties that drive performance in vivo. To elucidate these properties, drug-containing poly(lactic acid) (PLA)-poly(ethylene glycol) (PEG) block polymeric NP formulations (or PNPs) were sub-divided into discrete size fractions and analyzed using a combination of advanced techniques, namely cryogenic transmission electron microscopy, small-angle neutron and X-ray scattering, nuclear magnetic resonance, and hard-energy X-ray photoelectron spectroscopy.
View Article and Find Full Text PDFNanoparticles used for medical applications commonly possess coatings or surface functionalities intended to provide specific behavior , for example, the use of PEG to provide stealth properties. Direct, quantitative measurement of the surface chemistry and composition of such systems in a hydrated environment has thus far not been demonstrated, yet such measurements are of great importance for the development of nanomedicine systems. Here we demonstrate the first use of cryo-XPS for the measurement of two PEG-functionalized nanomedicines: a polymeric drug delivery system and a lipid nanoparticle mRNA carrier.
View Article and Find Full Text PDFQuantitative analysis of binary mixtures of tris(2-phenylpyridinato)iridium(III) (Ir(ppy)) and tris(8-hydroxyquinolinato)aluminum (Alq) by using an artificial neural network (ANN) system to mass spectra was attempted based on the results of a VAMAS (Versailles Project on Advanced Materials and Standards) interlaboratory study (TW2 A31) to evaluate matrix-effect correction and to investigate interface determination. Monolayers of binary mixtures having different Ir(ppy) ratios (0, 0.25, 0.
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