Create Analyte Schemes

Analyte schemes combine analytes, units, and methods to create the smallest unit of analytical work in AssayNet LIMS. Configuring them can be complex, especially when dealing with calculated analyte schemes.

Each analysis code is assigned the necessary number of schemes to calculate final results. A single analysis code may include multiple schemes depending on the complexity of the calculations involved. AssayNet LIMS can perform complex calculations across multiple schemes.

During implementation, your site provides an Excel worksheet with the required elements and formulas to be accurately replicated in the system. Keep in mind that the format of formulas in AssayNet LIMS may differ slightly from those used in standard spreadsheets.

In simpler analyses—where results are provided directly by the instrument—typically two analyte schemes are configured: one for the raw result (for example, Au Read) and one for the calculated result (for example, Au).

In this example, values are entered or imported into Au Read, and then Au is calculated based on that value, along with any required factors, unit conversions, or weight/volume calculations. Even when the raw and calculated values are identical, it is standard practice to separate them. This provides flexibility for future adjustments without altering the raw data source.

Analyte schemes can also be used to enter non-numeric values, including dates.

This activity describes how to create a new analyte scheme or clone an existing scheme.

This activity presumes that Methods and Analytes are configured for the analyte schemes. For more information, see Create and Configure Methods and Create Analytes.

Activity Steps

On the Profile ribbon tab, under the Analysis group, click Analyte Schemes.
The Analyte Scheme screen displays.
Click New.
The Add Analyte screen displays.
1. Complete the following fields as required:
  - Analyte—For example, Au, Ag.
    Note: Use Analyte Type to filter the analyte.
  - Analysis Method—In most cases, you should create the necessary analyte schemes for each method separately, even if the analysis is for the same element. For example, FA-AA (Fire Assay with Atomic Absorption finish) and FA-GR (Fire Assay with Gravimetric finish) may both analyze Au, but you should create a separate set of analyte schemes for each method.
  - Scheme Code—The scheme code should have a unique identifier code, generally the name code for the analyte method. For example, Au Read.
  - Scheme Name
  - Raw Units—The unit corresponding to the raw data. This may be the unit of display or output of the instrument that is reading the samples (if any).
  - Converted Unit—The first post-instrument unit, before any additional processing has been done on the results. The converted unit is often the same as the raw unit.
  - Display Unit—The display unit is the unit in which the final result will be displayed or reported. When there is a unit conversion, the Display Unit is the same as the Converted Unit. Otherwise, all unit fields share the same unit.
  - Prep Product—Link the analyte scheme to a specific prep product if required. In most cases, you do not need to link schemes to prep products unless the analysis requires separate handling for individual products and the scheme needs to display values or perform calculations for a specific product.
  - Standard—Link the analyte scheme to a specific standard if required. In most cases, you do not need to link schemes to a standard unless the analysis requires separate handling for individual standards and the scheme needs to display values or perform calculations for a specific standard.
  - Sample Split—Link the analyte scheme to a specific sample split (preparation duplicate) if required. In most cases, you do not need to link schemes to a sample split unless the analysis requires separate handling for individual sample splits and the scheme needs to display values or perform calculations for a specific split.
  - Linked Scheme—When you create replicate schemes (for example, Au-1, Au-2, and Au-3; see the Replicate field description), set the linked scheme for each one to the source scheme—for example, Au. If one of the replicates is placed on hold at the sample level, the source scheme (Au) is automatically placed on hold at the analysis level. When you recalculate, LIMS excludes the held replicate from the average.
  - Date Format—You can select a date format for date value schemes.
  - CAS Number—A unique numerical identifier assigned to every chemical substance described in the open scientific literature.
  - Replicate—Link the analyte scheme to a specific sample replicate if required. In most cases, this is not required unless the analysis involves separate handling for individual replicates. You can configure separate schemes for each replicate, assigning a number that corresponds to the replicate it applies to. This allows the system to identify which replicate each scheme is assigned to.
  - Constant Value—In some cases, you may want an analyte scheme to automatically carry a constant numeric value. This is useful when the value is used as a factor in a calculated scheme and remains the same for all samples. Using this option avoids the need to manually enter the same value for each sample.
  - Value when no data—Use this option when you need to ensure a value is present for all samples, even if no value is entered or imported for a specific sample. This is especially important when the scheme is used in calculations involving division. A blank scheme is treated as zero, which can cause errors during calculation.
Click OK.
Note: After you complete the above fields, you must click OK to create the analyte scheme and enable the remaining fields. If you select Calculated Value under the Analyte Scheme Type category and do not click OK before you continue the configuration, an error message displays.
See Configure Analyte Schemes to continue the configuration.