Abstract: Devices and methods are provided that allow for the casting of flat, controlled thickness layers of gel or polymer on a test surface, such as within the wells of a microplate. A spacer device is interposed between the test surface and the planar lower face of a movable pillar, defining a highly uniform volume. Addition of a gel or polymer precursor in solution followed by curing generates a highly uniform gel or polymer layer with a planar upper surface within this volume, which is exposed on removal of the pillar. In some embodiments a group of pillars is provided in a manifold that provides spacing and arrangement corresponding to a group of test wells. The pillars are mounted in the manifold so as to provide translation movement normal to the test surface, allowing them to rest against the spacer device and facilitating gentle removal from the wells. A variety of spacer devices are considered, including beads, flattened rings, and toroidal spacers.

Abstract: Using 3D printing, a microwell is formed by providing a plurality of masks, each mask representing a cross-section of a layer of the concave structure. Progressive movement of a projection plane exposes a pre-polymer solution to polymerizing radiation modulated by the masks to define the layers of the microwell, where each layer is exposed for a non-equal exposure period as determined by a non-linear factor. In a preferred embodiment, a first portion of the masks are base layer masks, which are exposed for a longer period than subsequent exposure periods. Shapes of the microwells, which may include circular, square, annular, or other geometric shapes, and their depths, are selected to promote aggregation behavior in the target cells, which may include tumor cells and stem cells.

Abstract: Devices and methods are provided that allow for the casting of flat, controlled thickness layers of gel or polymer on a test surface, such as within the wells of a microplate. A spacer device is interposed between the test surface and the planar lower face of a movable pillar, defining a highly uniform volume. Addition of a gel or polymer precursor in solution followed by curing generates a highly uniform gel or polymer layer with a planar upper surface within this volume, which is exposed on removal of the pillar. In some embodiments a group of pillars is provided in a manifold that provides spacing and arrangement corresponding to a group of test wells. The pillars are mounted in the manifold so as to provide translation movement normal to the test surface, allowing them to rest against the spacer device and facilitating gentle removal from the wells. A variety of spacer devices are considered, including beads, flattened rings, and toroidal spacers.

Abstract: The inventive subject matter provides an apparatus for reproducibly fabricating hydrogel-based organ and tumor models inside multi-well plates. For example, tumor models made using the inventive apparatus can be used for studying the progression of cancer, cancer diagnostics, and therapeutic screening. A mold controls the thickness of each hydrogel layer. A photomask controls the size and shape of each hydrogel layer, allowing the hydrogel diameter to be smaller than the diameter of each well so that liquid media can be exchanged around both the sides and top of the hydrogels. A holder aligns the photomask with the multi-well plate, and polymerization is initiated by a light source.

Abstract: The inventive subject matter provides an apparatus for reproducibly fabricating hydrogel-based organ and tumor models inside multi-well plates. For example, tumor models made using the inventive apparatus can be used for studying the progression of cancer, cancer diagnostics, and therapeutic screening. A mold controls the thickness of each hydrogel layer. A photomask controls the size and shape of each hydrogel layer, allowing the hydrogel diameter to be smaller than the diameter of each well so that liquid media can be exchanged around both the sides and top of the hydrogels. A holder aligns the photomask with the multi-well plate, and polymerization is initiated by a light source.

Abstract: Using 3D printing, a microwell is formed by providing a plurality of masks, each mask representing a cross-section of a layer of the concave structure. Progressive movement of a projection plane exposes a pre-polymer solution to polymerizing radiation modulated by the masks to define the layers of the microwell, where each layer is exposed for a non-equal exposure period as determined by a non-linear factor. In a preferred embodiment, a first portion of the masks are base layer masks, which are exposed for a longer period than subsequent exposure periods. Shapes of the microwells, which may include circular, square, annular, or other geometric shapes, and their depths, are selected to promote aggregation behavior in the target cells, which may include tumor cells and stem cells.