Eye diseases and injuries impose a significant clinical problem worldwide. Safe and effective ocular drug delivery is, however, challenging due to the presence of ocular barriers. Here we report a strategy using an eye patch equipped with an array of detachable microneedles. These microneedles can penetrate the ocular surface tissue, and serve as implanted micro-reservoirs for controlled drug delivery. The biphasic drug release kinetics enabled by the double-layered micro-reservoirs largely enhances therapeutic efficacy. Using corneal neovascularization as the disease model, we show that delivery of an anti-angiogenic monoclonal antibody (DC101) by such eye patch produces ~90% reduction of neovascular area. Furthermore, quick release of an anti-inflammatory compound (diclofenac) followed by a sustained release of DC101 provides synergistic therapeutic outcome. The eye patch application is easy and minimally invasive to ensure good patient compliance. Such intraocular drug delivery strategy promises effective home-based treatment of many eye diseases.

Sensitive and quantitative assessment of changes in circulating tumor cells (CTCs) can help in cancer prognosis and in the evaluation of therapeutics efficacy. However, extremely low occurrence of CTCs in the peripheral blood (approximately one CTC per billion blood cells) and potential changes in molecular biomarkers during the process of epithelial to mesenchymal transition (EMT) create technical hurdles to the enrichment and enumeration CTCs. Recently, efforts have been directed toward development of antibody-capture assays based on the expression of the common biomarker - the epithelial cell adhesion molecule (EpCAM) of epithelium-derived cancer cells. Despite some promising results, the assays relying on EpCAM capture have shown inconsistent sensitivity in clinical settings and often fail to detect CTCs in patients with metastatic cancer. We have addressed this problem by the development of an assay based on hybrid magnetic/plasmonic nanocarriers and a microfluidic channel. In this assay cancer cells are specifically targeted by antibody-conjugated magnetic nanocarriers and are separated from normal blood cells by a magnetic force in a microfluidic chamber. Subsequently, immunofluorescence staining is used to differentiate CTCs from normal blood cells. We demonstrated in cell models of colon, breast and skin cancers that this platform can be easily adapted to a variety of biomarkers, targeting both surface receptor molecules and intracellular biomarkers of epithelial-derived cancer cells. Experiments in whole blood showed capture efficiency greater than 90% when two cancer biomarkers are used for cell capture. Thus, the combination of immunotargeted magnetic nanocarriers with microfluidics provides an important platform that can improve the effectiveness of current CTC assays by overcoming the problem of heterogeneity of tumor cells in the circulation.

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