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Characterization  Quality Control


 Quantitation of Proteins  BioSpec-nano





 Quantitation of Proteins Using   benefits

 BioSpec-nano                                                                                                      Cell Line Optimization
                       •  Measure the concentration of proteins or check the purity.
                       •  Measure sample quantities as small as 1 μL.
 Operating Principle and Features
                       •  Achieve low carryover with the automatic wiping function.
 The BioSpec-nano has two available optical path lengths, 0.2 mm and
 0.7 mm, and can quantify proteins and nucleic acids in sample quantities
 as low as 1 µL. Samples can also be measured using an optional cell with                                          Culture
 a 5 mm optical path length (for 2 mL sample quantities). That means
 only a small sample quantity is needed for quick protein concentration
 measurements or to check spectra.
 A wiping mechanism enables automatic cleaning between samples,
 ensuring extremely low carryover and reducing inconsistencies that
 may occur with manual cleaning (Fig. 1).

 Wipe


 Fig. 3   Analytical Condition Selection Window                                                                    Purification
 Results

 Measurement results are shown in Fig. 4. The results show a
 concentration of approx. 1000 μg/mL, which is the same as prepared.
 Target  Sample concentration values and spectra can be confirmed in the detail
 display window. Results can be output in either CSV or PDF format.
 Fig. 1   Automatic Wiping Function
 Measurement Method                                                                                                Characterization

 Measurement samples were prepared by diluting bovine immunoglobulin
 (IgG) to 1000 μg/mL with phosphate buffered saline. With the optical   Specifications
 path length set to 0.7 mm (Fig. 2), 4 μL of the sample was dripped onto
 the target to measure the optical density (OD) at 280 nm. The protein   Instrument  BioSpec-nano
 concentration is calculated based on the molar absorption coefficient (ε
 = 280) and molecular weight values entered in the software's analytical   Wavelength range  220 to 800 nm
 condition selection window (Fig. 3). The 280 ε value can also be   Spectrum bandwidth  3 nm
 calculated by the software if the number of tryptophan, tyrosine, and
 cysteine residues in the amino acid sequence is entered.  Wavelength accuracy  ±1 nm                              Quality Control
               Pathlength             0.2 mm, 0.7 mm
 4.6
               Photometric value unit  OD (Optical Density), absorbance converted with 10 mm pathlength
 The optical path length can be   3.45  Sample volume  1 µL min. (pathlength: 0.2 mm)
                                      2 µL min. (pathlength: 0.7 mm)
 selected by simply moving the lever.
               Light source           Xenon flash lamp
 2.3
               Monochromator          Holographic grating
               Detector               Photo diode array
 1.15
               Auto wiping function   Provided                                                                     Pharmacokinetics
               Spectrum measuring time  3 sec
 0
 Fig. 2   Optical Path Length Setting Area
 240  250  260  270  280  290  300  310  320  Quantitation range  Pathlength 0.2 mm, 1 to 75 OD, 50 to 3,700 ng/µL
 Conclusion  Wavelength (nm)          Pathlength 0.7 mm, 0.3 to 21 OD, 15 to 1,000 ng/µL
    Fig. 4   Analytical Results for 0.7 mm Optical Path Length  Optional 5 mm pathlength cell, 0.04 to 3 OD, 2 to 150 ng/μL
 Using the BioSpec-nano, sample concentrations can be measured from   Dimensions  W 210 mm x D 214 mm x H 417 mm
 small sample quantities of 1 to 4 μL by simply dripping the sample onto   Application Examples
 the stage. That eliminates any need for any manual processes, such as   Weight  7 kg                              Others
 raising/lowering an arm, placing a cell in position, or wiping off the sample   • Measuring single- or double-stranded DNA concentrations (refer to p. 6)  Analysis mode  Simple nucleic acid quantitation, labeled nucleic acid quantitation, protein quantitation,
 after each measurement. In addition to concentration determination, OD   • Measuring labeled nucleic acid concentrations  labeled protein quantitation, photometric measurement
 values can be displayed for any user-specified wavelength.  • Measuring RNA concentrations  Note: The droplet formation status will affect analysis results. Measure quantities that are large enough to enable proper droplet formation.



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