Microplates with UV permeable bottom wells

Abstract

Microplates and methods for manufacturing microplates. The microplate is designed to allow UV radiation to pass through the bottom wells of the microplate so that the microplate can be used for assaying samples by use of UV absorbance. In one embodiment, the microplate comprises at least first and second wells, each well having a UV permeable bottom. In another embodiment, the microplate comprises a frame having an upper portion and a lower portion contiguous with the upper portion and a sheet disposed between the upper portion and the lower portion and defining the bottom of at least one well of the microplate. One embodiment of the method includes steps of inserting a sheet of UV permeable material into a mold cavity that includes sections shaped to form the sidewalls of the plurality of wells, injecting molten plastic material into the mold cavity, and cooling the plastic material to form the microplate with the plastic material forming the sidewalls of each of the first and second wells and the sheet of UV permeable material forming the bottom of each of the first and second wells. Another embodiment of the method includes providing an upper plate defining sidewalls of at least one well, adhering an intermediate layer to the upper plate and adhering a sheet of UV permeable material to the intermediate layer. A further embodiment of the method includes inserting a sheet of material having at least one hole into a mold cavity, injecting a molten plastic material into the mold cavity and cooling the plastic material to form a microplate.

What is claimed is:  
     
       1. A microplate for use in assaying samples, comprising: 
       a frame that forms sidewalls of at least one well; and  
       a first layer that forms a bottom of the at least one well, the first layer being formed from a plastic material having an average optical density that is no more than approximately 0.09 at a thickness of approximately 7.5 mils between wavelengths of approximately 200 nm and approximately 300 nm;  
       the bottom of the at least one wall having a thickness of less than approximately 14 mils.  
     
     
       2. The microplate according to  claim 1 , wherein the plastic material is a chlorotrifluoropolyethylene. 
     
     
       3. The microplate according to  claim 1 , wherein the bottom of the at least one well has a thickness of from approximately 2 mils to approximately 9 mils. 
     
     
       4. The microplate according to  claim 1 , wherein the frame and the first layer are molded together. 
     
     
       5. The microplate according to  claim 1 , wherein the frame is formed from a composite material including a filler and a base plastic material, the composite material having an optical density of no more than approximately 0.09 at a thickness of approximately 7.5 mils between wavelengths of approximately 200 nm and approximately 300 nm. 
     
     
       6. The microplate according to  claim 1 , wherein the frame is formed from a composite material including a filler and a base plastic material, the composite material having an average optical density of more than approximately 0.09 at a thickness of approximately 7.5 mils between wavelengths of approximately 200 nm and approximately 300 nm. 
     
     
       7. The microplate according to  claim 1 , farther comprising an intermediate layer disposed between the frame and the first layer. 
     
     
       8. The microplate according to  claim 7 , wherein the intermediate layer is formed from a hot melt adhesive. 
     
     
       9. The microplate according to  claim 8 , wherein the hot melt adhesive is an ethylene vinylacetate. 
     
     
       10. The microplate according to  claim 7 , wherein the intermediate layer includes a hole disposed above the bottom of the at least one well. 
     
     
       11. The microplate according to  claim 1 , wherein the at least one well includes first and second wells respectively having first and second bottoms, and wherein a difference between an average optical density of the first and second bottoms between wavelengths of approximately 200 nm and approximately 300 nm is no more than approximately 0.09. 
     
     
       12. A microplate for use in assaying samples, comprising: 
       a frame including an upper portion and a lower portion, the upper portion defining sidewalls of at least one well, the upper portion and the lower portion being contiguous; and  
       a sheet defining a bottom of the at least one well, at least a portion of the sheet being disposed between the upper and lower portions of the frame;  
       the sheet having an average optical density that is no more than approximately 0.09 at a thickness of approximately 7.5 mils between wavelengths of approximately 200 nm and approximately 300 nm.  
     
     
       13. The microplate according to  claim 12 , wherein the upper and lower portions of the frame are a single molded piece. 
     
     
       14. The microplate according to  claim 12 , wherein the at least one well includes first and second wells, and wherein the lower portion includes a rib disposed between the first and second wells. 
     
     
       15. The microplate according to  claim 12 , wherein the at least one well includes a plurality of wells, and wherein the lower portion includes a grid of ribs, each of the ribs being disposed between adjacent ones of the plurality of wells. 
     
     
       16. The microplate according to  claim 12 , wherein the sheet has an outer edge, and wherein the lower portion of the frame includes at least one cleat disposed beneath at least a portion of the outer edge of the sheet. 
     
     
       17. The microplate according to  claim 12 , wherein the sheet has an outer edge, and wherein the lower portion of the frame includes a cleat disposed beneath the entire outer edge of the sheet. 
     
     
       18. The microplate according to  claim 12 , wherein the at least one well includes first and second wells respectively having first and second bottoms, and wherein a difference between an average optical density of the first and second bottoms between wavelengths of approximately 200 nm and approximately 300 nm is no more than approximately 0.09. 
     
     
       19. The microplate according to  claim 12 , wherein the bottom of the at least one well has a thickness of less than approximately 14 mils. 
     
     
       20. The microplate according to  claim 12 , wherein the bottom of the at least one well has a thickness of from approximately 2 mils to approximately 9 mils. 
     
     
       21. The microplate according to  claim 12 , wherein the sheet is formed from a polychlorotrifluoroethylene. 
     
     
       22. The microplate according to  claim 12 , wherein the frame and the sheet are molded together. 
     
     
       23. The microplate according to  claim 12 , wherein the frame is formed from a composite material including a filler and a base plastic material, the composite material having an optical density of no more than approximately 0.09 at a thickness of approximately 7.5 mils between wavelengths of approximately 200 nm and approximately 300 nm. 
     
     
       24. The microplate according to  claim 12 , wherein the frame is formed from a composite material including a filler and a base plastic material, the composite material having an average optical density of more than approximately 0.09 at a thickness of approximately 7.5 mils between wavelengths of approximately 200 nm and approximately 300 nm. 
     
     
       25. A microplate for use in assaying samples, comprising: 
       
         a frame that forms sidewalls of at least one well; and  
       
       
         a first layer that forms a bottom of the at least one well, the first layer being formed from a plastic material having an average optical density that is no more than approximately  0 . 09  at a thickness of approximately  7 . 5  mils between wavelengths of approximately  260  nm and approximately  280  nm;  
       
       
         the bottom of the at least one well having a thickness of less than approximately  14  mils. 
       
     
     
       26. A microplate for use in assaying samples, comprising: 
       
         a frame that forms sidewalls of at least one well; and  
       
       
         a first layer that forms a bottom of the at least one well, the first layer being formed from a plastic material having an optical density that is no more than approximately  0 . 09  at a thickness of approximately  7 . 5  mils at a wavelength of  280  nm;  
       
       
         the bottom of the at least one well having a thickness of less than approximately  14  mils. 
       
     
     
       27. A microplate for use in assaying samples, comprising: 
       
         a frame that forms sidewalls of at least one well; and  
       
         a first layer that forms a bottom of the at least one well, the first layer being formed from a plastic material that allows greater than approximately  80   %  radiation transmission therethrough at a thickness of approximately  7 . 5  mils at a wavelength of  280  nm;    
       
         the bottom of the at least one well having a thickness of less than approximately  14  mils.