Vinci

Data Acquisition

Vinci offers several routines for the prompt acquisition of fluorescence data:

• Spectra (excitation, emission, synchronous, excitation and emission matrices)
• Fast and slow kinetics (intensity, polarization and ratiometric)
• Time-resolved measurements (lifetimes and anisotropy decays)
• User-designed measurements

Once the user defines the experiment control parameters and initiates Data Acquisition, the instrument no longer requires the presence of an operator. Multiple data files can be acquired and saved automatically. During Data Acquisition, measurement results are displayed graphically and numerically in real-time.

User-Designed Protocols

The user can also design a series of measurements with customized experimental conditions of his/her own choice and save this protocol as an Experiment file for later use.

Experiment Files with Exact Measurement Conditions

Each Experiment file contains not only the raw data but also the experimental conditions for the measurement. Once a saved Experiment file is reloaded, the measurement can be repeated with the exact same experimental conditions (wavelength range, acquisition time, frequency range, etc.). Experiment files are never modified; once a modification is made, the user is required to save the modified file under a new file name.

One-Dimensional and Multi-Dimensional Experiments

Acquisition protocols are classified as one- or multi-dimensional experiments. One-dimensional experiments include e.g. the acquisition of emission spectra (intensity versus wavelength); time-traces (intensity versus time) and single-point polarization measurements as well as the measurement of the fluorescence decay times at a set temperature of a sample.

Multidimensional experiments include the acquisition of a series of emission spectra at different temperatures, polarization measurements at different excitation and emission wavelengths, and the acquisition of lifetimes at different pressures, or excitation wavelengths.

Adaptive Data Acquisition

For the acquisition of both, steady-state and time-resolved data, the user has two options for Signal Averaging of each data point: Acquisition Time or Standard Deviation.

When Acquisition Time is chosen, different data points may have a different standard deviation. Alternatively, when the Standard Deviation option is used, data acquisition will continue until the desired standard deviation is reached. The software is adaptive, and automatically optimizes the acquisition time for each data point according to its noise level: data points with a higher noise require additional acquisition time; conversely, measurement of data points with less noise require less time.

Automatic Correction of Instrument Artifacts

ISS instruments also feature automatic correction of instrumental artifacts:

• Dark Count Correction: The light detectors dark current is periodically evaluated by Vinci and automatically subtracted from the acquired data.
• Correction of the intensity output of the lamp: Excitation spectra are automatically corrected for the intensity output of the lamp by using a quantum counter placed in the reference channel of the spectrofluorometer.
• Correction of instruments spectral response: Emission spectra are automatically corrected for the instrument's spectral response during acquisition by applying the correction factors provided with the instrument.

Background Subtraction in Steady-State and Time-Resolved Measurements

Biological samples exhibit background fluorescence, a condition that alters and compromises the quality of the fluorescence signal. Vinci offers an option to automatically correct the background fluorescence of the samples both, in steady-state- and time-resolved-mode.