The term “microfluidics devices” generally refers to systems that utilize sub-milliliter volumes. The use of microfluidics has expanded greatly in the past decade, driven by demands in research and diagnostics. In research applications the microfluidic device can minimize the use of valuable reagents and samples, and also provide parallel processing for higher-throughput experiments in the fields of ‘-omics’. Similar demands for contained microfluidic devices exist in diagnostics in order to reduce assay costs, enable higher throughput by centralized service centers, and also to accommodate automated systems that reduce user error. Grace Bio-Labs manufactures economical microfluidic devices for rapid setup and flexible design used in laboratory experiments, diagnostics and manufacturing processes. Our microfluidic devices are constructed for bio-compatibility, and may be customized for specific protocols including organic solvents, extreme pH or temperature.
Other applications for microfluidics involve the study of fluid behavior in the micro-scale, influenced by surface tension, capillary forces, energy dissipation, and regional concentration variations. The field of microfluidics studies how fluids can be manipulated in small volumes and the potential affects on chemical reactions within small chambers. Microfluidics is also applicable to studies of microbial behavior, including motility, chemotaxis and adherence.
Microfluidics create powerful tools for cell biologists in the growing field of single cell analysis. In these experiments, individual cells may be isolated, cultured and examined for responses to environmental changes. These studies often involve microscopic analysis, and so require a microfluidic device compatible with high-resolution imaging.
FLEXWELL INCUBATION CHAMBERS
FlexWell(tm) incubation chambers are created by silicone gaskets on standard 25 x 75mm microscope slides for parallel processing of small samples and high-throughput applications. The Flexwell incubation chambers come in 8, 16 and 64-chamber format, and these incubation chambers may be produced on a custom basis to dimensions of choice. Standard spacing for these incubation chambers are compatible with multi-channel pipettors. Sealing strips are available to minimize evaporation and cross-contamination. Applications include cell labeling or incubations with multiple conditions, microarray analysis with multi-array per slide format, in situ hybridization and microscopy.
FlexWell incubation chambers are chemically inert and adhere to glass surfaces with adhesive that has been tested for bio-compatibility, and is generally compatible with conditions used on biological samples. Ask for technical support if your experimental conditions involve solvents or extreme temperature or pH, and for more information on FlexWell incubation chambers.
Published applications for these incubation chambers include cell labeling or incubations with multiple assay conditions, microarray analysis with multi-array per slide format, in situ hybridization and microscopy. View published protocols using the FlexWell incubation chambers in our reference section.
HYBRIDIZATION CHAMBER
A hybridization chamber is used to contain a reaction and minimize evaporation during the assay period. Grace Bio-Labs manufactures several versions of hybridization chambers, nearly all are microfluidic devices, designed to hold sub-milliliter volumes. A microfluidic device offers several advantages: it conserves valuable sample and reagent volumes, it can reduce the time required for hybridization and it can facilitate automated or robotic handling for high-throughput applications. Microfluidic devices with multiple chambers can also be used for parallel processing of samples, which can minimize variability in comparative studies.
For short assay times, open hybridization chambers may be used, as evaporation may not be a concern. For longer assay times, or if small concentration changes due to evaporation are a concern, then a sealed hybridization chamber is more desirable. Many of our hybridization chambers are designed to adhere to microscope slides and include port seals for sealing the chamber.
For active mixing during hybridization a larger fluid volume may be desired. Small volume chambers may restrict mixing efficiency due to fluid dynamics including surface tension, which can counteract shear forces created by mixing. Thus the ratio of sample volume to chamber volume should be considered when using a microfluidic device. One common practice to ensure active mixing in a small closed chamber is to partially fill the chamber, leaving a bubble. As the chamber is rotated or shaken, the movement of the bubble facilitates active mixing throughout the chamber.
FASTWELL(TM) REAGENT BARRIER
FastWell(tm) reagent barriers create open chambers or a reagent reservoir on glass without use of adhesive. The FastWell reagent barrier consists of a non-reactive silicone slide gasket that sticks to a standard glass microscope slide or other plain glass surfaces. The silicone slide gaskets can be stacked to create variable depths and volumes. Multiple FastWell reagent barriers can be placed on a microscope slide for parallel processing of samples. The silicone slide gasket removes cleanly from glass surfaces and may be reused. A FastWell reagent barrier may be sealed with glass slide or coverslip to avoid evaporation during assays or for storing samples.
Applications for these silicone slide gaskets include monitoring enzyme reactions, casting hydrogels on glass surfaces, staining mutliple tissue samples, creating micro-wells for serial dilution studies, microscope studies on mouse embryos, imaging spacers for microscopy, and rapid setup of a micro-well reagent reservoir on glass.
PRESS-TO-SEAL SILICONE ISOLATORS
Silicone Isolators from Grace BIo-Labs are available in a variety of shapes and format, with or without adhesive. The press-to-seal silicone isolators facilitate rapid setup of open chambers on any glass surface. These silicone slide gaskets are generally designed to fit on a standard 25 x 75mm microscope slide, though other sizes and sheets are available. The press-to-seal silicone isolators release cleanly from glass, and can be ordered with adhesive on one side, on both sides, or without adhesive. The silicone slide gaskets without adhesive adhere readily to clean glass surfaces, and retain their seal when completely immersed in liquid, as during washing procedures. Without adhesive, the press-to-seal silicone isolators are reusable and can be autoclaved. They are resistant to most solvents and a broad range of pH. Press-to-seal silicone isolators can be sealed with a glass coverslip or the Hybrislip(tm) covers from Grace Bio-Labs.
HYBRISLIP(TM) HYBRIDIZATION COVERS
HybriSlip(TM) hybridization covers replace glass coverslips with a more hydrophopic and easier to handle hybridization cover. They are ideal for in situ hybridization, in situ PCR and microarray incubation. Made of thin polycarbonate (0.25mm), these slide coverslips do not chip or break, are less rigid than glass, do not curl, and are clear. Hybrislip hybridization covers can be used to reduce evaporation during relatively short incubations. As hybridization covers, these coverslips maintain samples flat and retain reagents over specific samples through surface tension and also prevent dust or particles from contaminating the sample. Hybrislip hybridization covers are shipped DNase and RNase free with a protective liner that is easily removed before use.
IMAGING & MICROSCOPY
Grace Bio-Labs manufactures many imaging and microscopy products in the form of press-to-seal chambers for sample assays on glass. Today, many biologists use techniques for molecular or chemical imaging in addition to microscopy. For all of these techniques, it is important to contain samples and reagents in a small volume to conserve both valuable samples and costly reagents.
Imaging and microscopy products from Grace Bio-Labs offer a variety of micro-chambers (generally sub-milliliter) to address different chemistries. Our silicone gaskets and seals are highly temperature and chemically resistant, and come with or without adhesives with different properties. One concern for scientists, for example, is compatibility of materials with fluorescent label detection. Background fluorescence from materials can lower assay sensitivity. As a solution, we offer a ‘fluorescent friendly’ form of our press-to-seal products that minimizes interference with fluorescence detection.
Clean release of adhesives is also a concern, as any residue left on the sample glass can interfere not only with imaging, but with robotic handling by automated instruments. The adhesives used on our press-to-seal imaging and microscopy products have been tested with uncoated glass for clean release. We have tested some coated surfaces to find the right adhesive that give a clean release, and can offer samples for you to test prior to setting up your experiment.
