Glaucoma is a leading cause of irreversible vision loss predicted to affect more than 100 million people by 2040. Intraocular pressure (IOP) reduction prevents development of glaucoma and vision loss from glaucoma. Glaucoma surgeries reduce IOP by facilitating aqueous humor outflow through a vent fashioned from the wall of the eye (trabeculectomy) or a glaucoma drainage implant (GDI), but surgeries lose efficacy overtime, and the five-year failure rates for trabeculectomy and tube shunts are 25-45%. The majority of surgical failures occur due to fibrosis around the vent. Alternatively, surgical procedures can shunt aqueous humor too well, leading to hypotony. Electrospinning is an appealing manufacturing platform for GDIs, as it allows for incorporation of biocompatible polymers into nano-or micro-fibers that can be configured into devices of myriad combinations of dimensions and conformations. Here, small-lumen, nano-structured glaucoma shunts were manufactured with or without a degradable inner core designed to modulate aqueous humor outflow to provide immediate IOP reduction, prevent post-operative hypotony, and potentially offer significant, long-term IOP reduction. Nano-structured shunts were durable, leak-proof, and demonstrated biocompatibility and patency in rabbit eyes. Importantly, both designs prevented hypotony and significantly reduced IOP for 27 days in normotensive rabbits, demonstrating potential for clinical utility. Glaucoma is a disease of the optic nerve and a leading worldwide cause of irreversible vision loss. Over 60 million people were affected by glaucoma in 2010, and more than 12 million will be bilaterally blind due to glaucoma by 2020. Glaucoma will affect more than 110 million individuals by 2040 1,2. Intraocular pressure (IOP) reduction prevents glaucoma progression and vision loss 3,4. Clinically, ophthalmologists use a variety of approaches to lower IOP, including medications, laser procedures, and/or incisional surgeries. Topical medications are first-line therapy in most cases as they reduce IOP while avoiding complications such as bleeding, infection, and hypotony that can reduce vision and are associated with incisional surgeries. However, topical medications do not always

Hydrogels, electrospun fiber mats (EFMs), and their composites have been extensively studied for tissue engineering because of their physical and chemical similarity to native biological systems. However, while chemically similar, hydrogels and electrospun fiber mats display very different topographical features. Here, we examine the influence of surface topography and composition of hydrogels, EFMs, and hydrogel-EFM composites on cell behavior. Materials studied were composed of synthetic poly(ethylene glycol) (PEG) and poly(ethylene glycol)-poly(ε-caprolactone) (PEGPCL) hydrogels and electrospun poly(caprolactone) (PCL) and core/shell PCL/PEGPCL constituent materials. The number of adherent cells and cell circularity were most strongly influenced by the fibrous nature of materials (e.g., topography), whereas cell spreading was more strongly influenced by material composition (e.g., chemistry). These results suggest that cell attachment and proliferation to hydrogel-EFM composites can be tuned by varying these properties to provide important insights for the future design of such composite materials.

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Rapid, specific and accurate proton nuclear magnetic resonance spectroscopy (1H NMR) method was developed to determine metformin hydrochloride antidiabetic drug in pharmaceutical tablet formulation. The method was based on quantitative NMR spectroscopy (qNMR) using maleic acid as an internal standard and deuterium oxide (D2O) as a diluent. For the quantification of the drug, the (1H NMR signals at 2.91 ppm and 6.25 ppm corresponding to the analyte proton of metformin hydrochloride and maleic acid internal reference standard (IS) respectively were used. The method was validated for the parameters of specificity and selectivity, precision and intermediate precision, linearity, range, limit of detection (LOD) and limit of quantification (LOQ), accuracy, solution stability and robustness. The linearity of the calibration curve for analyte in the desired concentration range was good (R2=0.9993). The method was accurate and precise with good recoveries. Range study was also performed up to saturation level (152.67 mg/0.60 mL) in D2O. The advantage of the method is that no reference standard of analyte drug is required for quantification. The method is nondestructive and can be applied for quantification of metformin hydrochloride in commercial formulation products.