Drug discovery screening system, AP-3000 offers functions and features listed below. Please select them from the following list and review.

AP-3000 has a sensor with 6 pairs of cells where measurements are taken simultaneously. The pipetters that are installed within AP-3000 speedily aspirate from plates and inject into sensors the analyte solutions, and therefore the maximum of 3,840 measurements (10 x 384-well plates) can be done in about 18 hours and 30 minutes. Including the time for setting samples and consumables in the instrument (about 1 hour), it is possible to measure 10 384-well plates per day.

SPR (Surface Plasmon Resonance), the principle technology of AP-3000, detects changes in the refractive index, and therefore the smaller the molecular weight of compounds is, the more difficult it is to measure the compounds.
However, AP-3000 is able to detect signals at low noise level, using highly sensitive sensors and an optical detection method, and therefore makes it possible to detect binding of the compounds with low molecular weight, which can be as low as 100Da, and to perform fragment screening effectively.

For assays of small molecular compounds with low solubility, an organic solvent such as DMSO is often used to improve solubility. AP-3000 is able to operate at the maximum concentration of 12% DMSO. When the highly concentrated DMSO is used, evaporation which takes place during the measurement may cause signal deviation. With the AP-3000 sensor, having flow paths with small openings, evaporation rarely takes place.

SPR based binding assays consist of the following steps.
- Sensors are placed in the detection unit and removed from the area after measurements are taken.
- Target proteins are immobilized on the sensor surface.
- Calibration solution is injected and measured.
- Analyte solution is injected and binding is measured.
- Binding values are calculated from the measurement data for calibration and analyte solutions
AP-3000 does all these steps automatically, and thus once samples, buffers and other consumables are set up and the screening is initiated, the instrument can be left alone until the screening is finished.

The data mining software, Spotfire DecisionSite for AP-3000 is installed on the computer externally connected to AP-3000. After each data is taken, it is automatically forwarded to the computer, and details of the data can be analyzed, while the screening is going on.
If there is any concern about what is going on during the screening, the state of the measurement can be reviewed by Sporfire DecisionSite for AP-3000.

Analysis of the data taken on AP-3000 can be performed by Spotfire DecisionSite for AP-3000, the software installed on the computer externally connected to the instrument.
Spotfire DecisionSite for AP-3000 is the Spotfire DecisionSite with the module customized specifically for AP-3000 for analysis purposes.

Data taken on AP-3000 is automatically analyzed by Spotfire DecisionSite for AP-3000, and histograms for binding signals, dose response plots, sensorgrams for protein immobilization and binding of compounds, and other visualization are automatically drawn.
Spotfire DecisionSite for AP-3000 also performs normalization, using blank signals and positive controls. Moreover, other analysis functions are included in the module, such as calculations of the affinity constant, KD by curve fitting, and the dissociation rate constant, kd using dissociation curves. Using these functions, abundant information taken by AP-3000 can be promptly analyzed.

This exclusive module works only on the computer externally connected to AP-3000, and therefore will not work on the Spotfire DecisionSite which is commercially available. However, the analysis results stored in a Spotfire format (sfs file) can be usually viewed with any Spotfire DecisionSite, and therefore Spotfire DecisionSite license users can share the analysis results from AP-3000.

AP-3000 performs measurement, using SPR technology. SPR enables detection of direct binding without labels, and this simplifies examination of conditions prior to a screening.
Moreover, there are the following merits which functional assays or competitive assays do not offer.

Binding signals depend on the number of compounds bound to proteins, and their molecular weight.
Stoichiometric ratio between immobilized proteins and binding compounds can be calculated.

Signals change when compounds bind to a target protein.
Binding of a compound to the site of a target protein other than the active site can be detected.

AP-3000 has capability to skip measurement of compounds located at any specific wells on a plate. Using this function, the compounds which the prescreening identifies as those not to be further measured do not get injected into the flow paths in the sensors, and therefore will not be measured. Accordingly, analyte plates for prescreening and those for main screening are exactly the same, and therefore, it is not necessary to reconstruct plates at each screening. This makes preparation of analyte plates simple and easy.
Using the results of analysis by the Spotfire, the compounds which are to be skipped are identified visually as shown below on the right, and this information is transferred to the internal computer and used to automatically skip injection of those compounds into the sensors. Even when there are many compounds which should be skipped, the skipping operation is easily carried out.

When detecting a large number of compounds by SPR, it is required to measure multiple compounds repeatedly at the same area of protein immobilization in order to minimize protein consumption. AP-3000 sensor stick can be used repeatedly 400 times at maximum (the maximum number depends on measurement protocols.) When 5ug(100ug/mL x 50uL)of a protein is injected and immobilized at one area, and analyte binding is measured 400 times at that area, the amount of the protein used for one analyte measurement is merely 12.5ng.

Although analysis based on SPR provides highly precise, valuable information, it usually makes maintenance very difficult because precision parts and micro flow-paths are used. AP-3000 eliminates this problem. AP-3000 uses a specially developed sensor stick which has each flow-path and prism combined into one and is made of plastic, and thus all the parts which are exposed to compound solutions are disposable.
The flow-path is short and relatively wide. This makes it difficult for it to be clogged up with precipitated compounds, and it is possible to take measurement with a small amount of solutions. In case the flow-path gets clogged up, a user can replace a whole sensor stick with a new one, and solve the problem, and this allows the measurement taking to continue smoothly. Because of this, it is possible to do experiment with crude samples and low soluble samples, and increase flexibility of experiments.

The process of SPR analysis is that after a target protein is immobilized on a sensor surface, an anlyte solution is injected, and the change is detected.
The target protein sometimes loses its activity at the time of immobilization. It is possible to confirm if or not there is a loss of activity by measuring the binding between the immobilized protein and positive control compounds. But still there is a possibility of nonspecific binding taking place between positive control compounds and the protein which has lost activity or been denatured.

This function to recover substrate solutions makes it possible to measure the activity of an immobilized protein directly, in case of the target protein being an enzyme. This is done by injecting, mixing and incubating the substrate solution, recovering the solution into a plate, and confirming if or not there is the reaction, using a plate reader.

In most cases, the higher the throughput is, the more desirable the screening is. On the other hand, in case of verifying reproducibility of hit compounds or calculating KD values from dose response, high precision takes higher priority than throughput.
AP-3000 has the planning software, Planner, which provides the ability to freely customize the measurement protocols. By editing solution injection protocols using the Planner, the measurement which prioritizes throughput, the precise measurement using regeneration or tip cleaning solutions, or the dose response measurement can be customized.
Inputting information such as the number of compounds to be measured, the Planner will display the needed number of sensor sticks, locations of reagents on a plate, and an estimated amount of time for measurements. Just as the data mining software, Spotfire DecisionSite for AP-3000, the Planner is installed on the computer externally connected to AP-3000, but if so desired, it can be installed on a user's own computer. The user can plan an experiment protocol on his/her computer, send it to AP-3000 and initiate the measurement. This makes it easy to plan the work schedule ahead of time.