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#Akta pure pc interface software#

Polymer analysis - replacing the HPLC’s dRI detector with an Optilab affords many benefits including direct digital data acquisition, matched MALS and RI wavelengths for more accurate molar masses, and concentration range up to ~ 20 mg/mL for convenient and accurate dn/dc measurements.ĪSTRA software can directly control select HPLC instruments, eliminating the need to synchronize the ASTRA method with native HPLC software.The same analysis is suitable for many copolymers. Bioconjugates - MALS, UV and dRI are combined for analysis of glycoproteins, AAVs, protein/DNA complexes, membrane proteins embedded in surfactants or lipids, and other dual-component biomacromolecules.Protein analysis - including an Optilab is very useful since nearly all proteins have the same dRI response ( dn/dc) - it is not necessary to know the extinction coefficient of each peak.Most SEC-MALS users find it beneficial to include an Optilab ® dRI detector, or microOptilab ™ for UHPLC. Native HPLC software or a hand-held controller is used to control the HPLC system. Sample injection and ASTRA data collection are synchronized via analog auto-inject signal, and concentration data are acquired via analog output from the concentration detector.MALS is plumbed downstream of the UV detector or upstream of the dRI detector.miniDAWN and microDAWN have 3 angular detectors they cover a molar mass range of 200 to 10 7 g/mol (10 6 g/mol for linear polymers), and a size range of 10 to 50 nm.DAWN has 18 angular detectors it covers a molar mass range of 200 to 10 9 g/mol and a size range of 10 to 500 nm with maximum sensitivity.HP/FPLC-SEC-MALS uses a DAWN ® or miniDAWN ® MALS instrument UHP-SEC-MALS requires a microDAWN ®.Learn more about these and other types of MALS measurements on the Other Techniques Application Notes page.įor basic SEC-MALS, all you need are a standard HPLC or FPLC system including a concentration detector (UV for proteins, dRI for polymers), SEC column(s), a MALS instrument and a computer with ASTRA ® software for data acquisition and analysis. Online MALS analysis give instant identification of peaks, with no need to collect and analyze offline.

MALS can also be combined with ion-exchange chromatography (IEX-MALS) and reverse-phase chromatography (RPC-MALS), which-unlike SEC-cannot be calibrated to assign a molar mass to any specific retention time. When that does not work, either due to analyte-column interactions or simply analytes beyond the useful size range of SEC, MALS can be coupled to a different separation technique, field-flow fractionation.

SEC-MALS is only effective if good separation is achieved on the SEC column. For more details on the theory of MALS, please see our MALS Theory page. In addition, the analyte’s dn/dc value (specific refractive index increment) in the mobile phase must be known or measured (this is easier than it sounds!). Most of the constants used to determine M and R g are related to system optical properties such as laser wavelength and solvent (mobile phase) refractive index.

Radius of gyration, R g, is calculated from the slope.

Molar mass, M, is calculated from the ratio of R(0) and the concentration.

angle is fit to determine R(0) (the y-intersect at angle θ = 0) and the slope. The MALS detector incorporates between 3 and 18 photodiodes positioned at different angles θ relative to the laser beam to measure the scattered light function R(θ). In UHP-SEC-MALS, the peaks are much narrower, so data are collected at roughly 10 times per second. In SEC-MALS, the function of the SEC column is to separate solution components by hydrodynamic size (due to column interactions, some components may elute in the opposite order, and components of the same size may elute at different times).Īs each component passes through the detectors, its concentration and light scattering properties are measured every second or so.

Dynamic & Electrophoretic Light Scattering.