The Screen Quest™ product series includes a variety of biological research materials for multiple applications. The series includes assay kits pertaining to multiple cellular activities, lab-engineered receptor-coupled cells, chimeric cell lines, and even optimized assay buffers. This wide range is reflective of an in-house optimization process that showcases careful component selection along with extensive quality testing.

The intracellular balance of physiologically important ions and transport in and out of organelles and the cell itself (ion flux) is a prominent research focus used to quantify healthy and aberrant cellular behavior. Calcium, Potassium, and Chloride ions are among the most commonly studied due to their roles in cellular and physiological process regulation, including respiration, heart rate, and pain. Ion channel defects cause multiple pathologies (e.g., cystic fibrosis), and errors in ion balance can indicate serious issues such as tumor formation.

Calcium is a central figure of cell signaling and function. Using indicator tags that bind preferentially with calcium, researchers visualize the changes in calcium concentration and the cellular actions facilitated by this ubiquitous ion. For screening G protein-coupled receptors (GPCRs), calcium flux assays are the most popular methodology. Each kit below is paired with a different proprietary indicator for different assay requirements to give efficient, reproducible results.

The ready-to-use Screen Quest™ 10X calcium assay buffer with Phenol Red Plus™ has been shown in multiple cases to increase the calcium assay window in both Screen Quest™ kits and general use.

Buffer Preparations and Recipes Tool For other buffer recipes, click the button to explore the Buffer Preparations and Recipes Tool.

For experiments requiring a highly sensitive assay, our luminescent coelenterazine-based kit is more suitable than the fluorescence-based calcium assay kits. The Screen Quest™ Luminometric Calcium Assay Kit uses a highly calcium-sensitive and membrane-permeable coelenterazine analog as a calcium indicator for the cells transfected with the apoaequorin gene. Aequorin is a calcium-sensitive bioluminescent protein from the jellyfish Aequorea victoria is used extensively as a calcium indicator in cells. The aequorin complex emits blue light when bound to calcium ions. The luminescence intensity is directly proportional to the Ca2+ concentration.

Both potassium and chloride ion channels facilitate cellular and physiological functions such as cell signaling and nerve impulse propagation. Ion-channel gating and related behavior is a prominent field of biological study. AAT Bioquest's assay kits address various experimental needs, providing sensitive, efficient results suitable for use with both low-scale processes and automation.

A healthy cell has a standard transmembrane potential of -70mV as a result of concentration gradients of a multitude of charged ions such as K+ and Cl-. This membrane potential serves multiple functions, including muscle contraction, and variations in charge are a useful source of information about cellular behavior and viability. Whereas the specific ion channel assay kits above are used to track movements of particular materials, these potential assay kits (in two separate fluorescent emission spectra) visualize overall changes in charge.

3',5'-Cyclic adenosine monophosphate (cAMP) is a prominent second messenger in cellular biology, assisting in transmitting signals received by the cell membrane receptors to intracellular functions. Measuring the activity of cAMP is a useful metric for assessing cell signaling and other functions.

Employing the effectiveness of the ELISA assay in both colorimetric and fluorimetric formats, these all-inclusive kits do not require acetylation and employ AAT Bioquests' proprietary Amplite™ substrates to generate a signal proportional to cAMP activity.

For experiments requiring extreme sensitivity, time-resolved formats are a popular choice to minimize background signals. The Screen Quest™ FRET No Wash cAMP Assay Kit employs a labeled anti-cAMP antibody and a paired tracer to differentiate between free and unlabeled cAMP molecules, giving precise quantification of cAMP concentration when compared to a cAMP standard.

The Screen Quest™ Live Cell cAMP Assay Service Pack provides real-time monitoring of intracellular cAMP change in a high-throughput format and does not require cell lysis. The assay works via the cell lines that contain either: an exogenous cyclic nucleotide-gated channel (CNGC) or the G-protein G?16. The channel is activated by elevated levels of intracellular cAMP, resulting in ion flux and cell membrane depolarization which can be detected with a fluorescent calcium indicator (such as Fluo-8^® AM and Cal-520™ AM). Co-expression of G?16 with specific non-Gq-coupled receptors will result in the generation of an intracellular calcium signal upon receptor stimulation. The Screen Quest™ Live Cell cAMP Assay Service Pack includes both cell lines and reagents.

AAT Bioquest offers a full catalog of G-Protein-Coupled Receptor Cells and Chimera Cell Lines suitable for live-cell cAMP assays and other applications.

Biomolecular sources of energy like glucose and fatty acids are necessary to fuel all cellular activity and function. Cells typically have dedicated methods of active transport of these valuable molecules across membranes and into the cell, where they can be processed and used. Measuring the rate and extent of biomolecular uptake provides useful information about cellular viability, as well as physiological information for pathologies such as diabetes.

Nearly all known organisms use glucose as a source of energy; tracking its movement across cell membranes is crucial in assessing cell viability and function. Traditional methods of tracking glucose uptake include radioactive probes, which have multiple cost and safety concerns. Using a glucose analog and associated specific sensors, the Screen Quest™ Glucose Uptake Assay Kits provide a safer, efficient method of measurement in either colorimetric or fluorimetric format.

Obesity and diabetes are growing global health concerns. Fatty acids of multiple kinds are a popular target for potential treatments, particularly in cell metabolism and transport. Embedded in the cell membrane of most mammals, including humans, fatty acid transporters actively move these biomolecules into the cell. Employing a sensitive fluorescence format and a proprietary substrate, the Screen Quest™ Fluorimetric Fatty Acid Uptake Assay Kit allows accurate quantification.

Chemotherapy is the dominant treatment in oncology, but its effectiveness decreases in tumors displaying multidrug resistance (MDR). MDR is the result of multiple factors, one of which is the overexpression of selected protein transport complexes in cell membranes. These ATP-dependent transporters are the target of the Screen Quest™ Fluorimetric MDR Assay Kit, which selectively shows intense fluorescence signaling in affected cells.