ECL`

AnalyzeDynamicLightScattering

AnalyzeDynamicLightScattering[DynamicLightScatteringData]⟹Object

Calculates the key scientific parameters derived from the dynamic light scattering protocol, including Z-average diameter, second virial coefficient (b22), diffusion interation parameter (kD), and Kirkwood Buff integral (G22).

AnalyzeDynamicLightScattering[DynamicLightScatteringProtocol]⟹Object

Analyzes all the data in the given protocol.

AnalyzeDynamicLightScattering[MeltingCurveData]⟹Object

Calculates the Z-average diameter, polydispersity index, and diffusion coefficient for MeltingCurve data objects generated from Object[Protocol, ThermalShift].

Details

Two particle sizing methods are available: the instrument calculation and the cumulants method based on International Organization of Standardization (ISO) 22414:2017
The cumulants method fits the decaying correlation curves with a single exponential that contains a polynomial in the exponent. Regarding the polynomial, the first order term represents the mean particle size, the second represents the variance, the third represents the skewness.
Correlation curves can be excluded from the analysis if their initial values are too low, indicating improper sample loading, or if the correlation curve does not converge near 0, indicating significant noise.
The diffusion coefficient is estimated by regressing the diffusion coefficient versus protein concentration. The ratio of the slope to y-intercept is the diffusion interaction parameter.
The second virial coefficient is estimated by regressing the optical constant times the concentration divided by the Rayleigh ratio versus concentration. Half of the slope is the second virial coefficient.
The Kirkwood Buff integral is estimated by regressing the Rayleigh ratio divided by the optical constant versus a first and second order coefficient term. The coefficient to the second order term divided by the molecular weight is the Kirkwood Buff integral.

Input

Output

General Options

Examples

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Basic Examples (3)

Analyze dynamic light scattering data to create an Analysis Object:

Calculate the diffusion interaction parameter:

Calculate the second virial coefficient:

Additional Examples (12)

Analyze all data within a DynamicLightScattering Protocol:

Analyze melting curve data to create an Analysis Object:

For AssayType B22kD, calculate the PolyDispersityIndices using the cumulants method:

For AssayType G22, calculate the Kirkwood-Buff Integral:

For AssayType G22, calculate the Z-average diameter using the cumulants method:

For AssayType G22, create analysis objects of all data in the protocol:

For AssayType IsothermalStability, calculate the DiffusionCoefficients:

For AssayType IsothermalStability, calculate the ZAverageDiameters using the cumulants method:

For AssayType IsothermalStability, create analysis objects of all data in the protocol:

For AssayType SizingPolydispersity, calculate the zAverageDiameters:

For AssayType SizingPolydispersity, calculate the zAverageDiameters using the cumulants method:

For AssayType ThermalShift, calculate the ZAverageDiameters using the cumulants method:

Options (14)

CalibrationStandardIntensity (1)

Specify the CalibrationStandardIntensity of toluene from the experimental set up used to calculate the second virial coefficient:

ConvergenceCorrelationThreshold (1)

Exclude correlation curves that do not drop below ConvergenceCorrelationThreshold, before the ConvergenceTimeThreshold (Correlation Curves tab):

ConvergenceTimeThreshold (1)

Exclude correlation curves that do not drop below ConvergenceCorrelationThreshold, before the ConvergenceTimeThreshold (Correlation Curves tab):

CorrelationMinimumMethod (1)

If the CorrelationMinimumMethod is Relative it scales the CorrelationMinimumValue to the initial correlation curve value, otherwise if CorrelationMinimumMethod is Absolute, the CorrelationMinimumValue is also the same number for all correlation curves:

CorrelationMinimumValue (1)

Include only correlation curve data above the CorrelationMinimumValue for particle size estimation:

InitialCorrelationMaximumThreshold (1)

Exclude correlation curves that, on average, are above the InitialCorrelationMaximumThreshold, before the InitialTimeThreshold (Correlation Curves tab):

InitialCorrelationMinimumThreshold (1)

Exclude correlation curves that, on average, are below the InitialCorrelationMinimumThreshold, before the InitialTimeThreshold (Correlation Curves tab):

InitialTimeThreshold (1)

Exclude correlation curves that, on average, are above the InitialCorrelationMaximumThreshold or InitialCorrelationMinimumThreshold, before the InitialTimeThreshold (Correlation Curves tab):

Method (1)

Calculate the diffusion interaction parameter using the Cumulants method:

OpticalConstant (1)

Specify the optical constnat used in the calculation of the second virial coefficient:

Output (1)

Set Output to Options to return the function options:

PolynomialDegree (1)

Calculate the diffusion interaction parameter using the Cumulants method with a PolynomialDegree of 2:

RefractiveIndexConcentrationDerivative (1)

Specify the RefractiveIndexConcentrationDerivative used in the calculation of the optical constant. The optical constant is ued in the calculation of the second virial coefficient:

Upload (1)

Set Upload to False to return a packet:

Messages (9)

BadInstrumentData (1)

Non-numeric data from the instrument was detected:

CurvesOutsideRange (1)

For MeltingCurve data, a warning is issued if the correlation curves are outside of specification:

CurvesOutsideRangeRemoved (1)

A warning of removed data is issued if the correlation curves are outside of the initial correlation minimum and maximum:

MinExceedsMax (1)

An error is thrown if the minimum correlation threshold exceeds the maximum value:

NonSpecificationOption (1)

If the CorrelationMinimumValue exceeds 0.05, a warning is thrown about being outside of ISO documentation protocol:

OverSpecifiedOpticalConstant (1)

The OpticalConstant and RefractiveIndexConcentrationDerivative cannot both be specified:

UnsupportedProtocol (1)

Only MeltingCurve data from the ThermalShift protocol can be used in AnalyzeDynamicLightScattering:

UseCumulantsMethod (2)

An error is thrown if the instrument is DLSPlateReader and the method is Instrument:

A warning is shown if the solvent is not water or toluene:

Last modified on Wed 27 Aug 2025 17:10:42