Phone : +91-3222-283306
Location : School of Bioscience (2nd Floor Sir JC Bose Lab Complex, opposite Vikramshila), CRF

Prof. Swagata Dasgupta
Department of Chemistry

Faculties can request Slots within the internal network.

Click here to Book.



To measure the molecular weight and the hydrodynamic and thermodynamic properties of a protein or other macromolecule.


Prof. Swagata Dasgupta
Department of Chemistry
Dr. Soumya De
Technical Staff
Central Research Facility


Analytical Ultracentrifuge

Name- Analytical Ultracentrifuge

Manufacturer- Beckman Coulter

Model- Proteomelab.XL-1

Year of Installation- 2017


Description Specifications

Set speed

1000 to 60,000 in increments of 100 rpm

Speed control

±20 rpm of the set speed (above 1000 rpm)

Speed display

indicates rotor speed in increments of 10 rpm at speeds below 1000 rpm and 100 rpm at speeds above 1000 rpm


Set time

Up to 999 hours and 59 minutes; HOLD for runs of unspecified length

Time display

Indicates time remaining in timed runs, time elapsed in HOLD runs, and estimated time remaining in ω2t runs


Set temperature

0 to 40 °C in 1°C increments

Rotor temperature after equilibration

±0.5°C of set temperature

Displayed rotor temperature after equilibration

±0.3°C of set temperature
Ambient temperature range 15 to 30°C
ω2t integrator

Calculate time for ω2t

up to 9.99x1014 radians squared per second

ω2t display

shows the accumulated ω2t to three significant digits(in exponential notation)
Analytical acceleration 5 to 400 rpm per second above 500 rpm;400 is maximum acceleration
Analytical deceleration 5 to 400 rpm per second above 500 rpm;400 is maximum deceleration
XL acceleration nine slow acceleration profiles from 0 to 500 rpm,maximum acceleration from 0 rpm to set speed
XL deceleration nine slow deceleration profiles from set speed to 500 rpm, no brake, maximum deceleration from set speed to 0 rpm
Key switch Used to select normal or locked operation; zonal operation not allowed
Instrument classification T: uses Beckman Coulter analytical rotors only; preparative and zonal operation not allowed

Analytical Specifications

Scanning UV/VIS Absorbance Optical System

Description Specifications
Wavelength range 190 to 800 nm
Photometric display range 0 to 3 absorption units
Scan steps

Radial scan mode

Up to 1650 data points per scan; radial increment step size 0.001 cm minimum,0.01 cm maximum

Wavelength scan mode

Up to 620 data points per scan; minimum wavelength increment step size 1.0 nm, maximum wavelength increment size 100 nm
Data rate

One absorbance reading every 20 ms (approximately), depending on

rotor speed
Replication/data averaging 1 to 99 averages per data point
Concentration range 5μg/ml-2mg/ml


Interference optical System

Description Specifications
Wavelength 660 nm
Camera resolution 2048 x 96 pixels
Laser 30 mW diode
Scan rate Approx every 5 seconds
Interferometer precision Approx ± 0.003 fringe
Concentration range 25μg/ml-5mg/ml


Name of the equipment: Analytical Ultracentrifuge

Physical data

Description Specifications

Instrument only

465 kg
Height (to top of control head)120.7 cm
Width 94.0 cm
Depth 67.3 cm
Ventilation clearances

side 5.1 cm, rear 15.2 cm

Electrical supply Class I (single phase,220/240V,50Hz)
Maximum heat dissipation into the room 1.0 kW
Humidity restriction Ë‚ 95 % (non condensing)
Noise level(measured 0.9 m or 3 ft in front of the instrument) 57 dB
Installation (overvoltage) category II
Pollution degree 2a

a. Normally only nonconductive pollution occurs; occasionally, however, a temporary conductivity caused by condensation must be expected.

Utility and Working Principal

The analytical ultracentrifuge is at present the most versatile, rigorous and accurate means for determining the molecular weight and the hydrodynamic and thermodynamic properties of a protein or other macromolecule. There is no other technique that is able to provide the same range of information with this precision and accuracy. This is because the method of sedimentation analysis is based on the sound platform of thermodynamics. All terms in the equation describing sedimentation behavior are experimentally determinable.

Many macromolecules including proteins have an inherent property to form aggregates which changes the molecular weight of the species formed, and analytical centrifugation provides valuable information regarding the molecular weight of the species. Analytical centrifugation can directly measure the molecular weights of solutes without having to rely on calibration or making assumptions concerning shape. It can detect a wide range of molecular weights ranging from small proteins to larger aggregates and also larger protein present in virus. Moreover the molecular weights of calibration standards used in electrophoresis prepared using sequencing techniques, for which analytical centrifugation are the best method.

Biomacromolecular recognition including its interactions with small molecules is an important part of bioscience. The sedimentation equilibrium methodology in the analytical ultracentrifuge is the only technique presently capable of analyzing such interactions over a wide range of solute concentrations, without interference in the chemical equilibrium. Weak interactions, in the order of 10-100 M-1 (association constant, Ka), cannot be studied using electrophoresis but can be effectively done with analytical centrifugation. Such interactions are also studied using absorbance, frequently by labeling with a chromophore. These can be easily studied using an analytical centrifuge.

Analytical ultracentrifuge is also a powerful technique for the characterization of nanomaterials, especially in the small size ranges (i.e., 1−10 nm). By centrifuging the particles at high centrifugal forces, it is possible to follow their concentration depletion profiles over time in order to determine the particle sedimentation coefficients, S. The small (1−10 nm) nanoparticles are the most difficult to detect but often the most biologically and environmentally relevant. Furthermore, the particle friction coefficient can also be determined in order to gain critical information on the particle form i.e. shape.

Detection mode -    a) Built-in scanning UV/Visible    b) Built-in Rayleigh interference optics

Sample holder - Preassembled cells for the two rotors: with sapphire window and/or quartz window

Sample Details


Contact Us

Location – School of Bioscience (2nd Floor Sir JC Bose Lab Complex, opposite Vikramshila)

Dr. Swagata Dasgupta

Department of Chemistry, Indian Institute of Technology, Kharagpur – 721302, West Bengal.


Dr.Soumya De

School of Bioscience,Indian Institute of Technology, Kharagpur – 721302, West Bengal.

List of Laboratories