Research on Protein Viscosity

Introduction:

Viscosity is a biological macromolecule drug such as protein/An important parameter of antibody preparations. Fluids are divided into Newtonian fluids and non Newtonian fluids. For Newtonian fluids, viscosity values are only related to temperature and not to shear rate; The viscosity value of non Newtonian fluids is not only related to temperature, but also to shear rate. Different viscosity behaviors may occur at different shear rates, and high concentrations of biological agents are typical non Newtonian fluids.

Why chooseVROCViscometer?

Before 2015, the United States Pharmacopeia included four viscosity measurement methods, numbered 9119129131911. Due to 911 being a capillary viscometer, 912 being a rotary viscometer, and 913 being a drop ball viscometer, which cannot accurately set the shear rate, they are only suitable for measuring Newtonian fluids. The rotational rheometer belongs to macroscopic rheometer counting. Although it can set the shear rate and is suitable for measuring non Newtonian fluids, the rotational rheometer requires rich operating experience, a large amount of samples, a limited range of shear rates, insufficient mechanical resolution for low viscosity samples, and is not a closed system, making it unsuitable for air sensitive and volatile samples; There are significant challenges in measuring the viscosity of biological agents and complex fluids.

Therefore,2015New edition of the United States Pharmacopeia, prior to inclusion4On the basis of viscosity measurement methods, an additional section has been included5A viscosity measurement method, namely914This method can set different shear rates and accurately and quickly measure the true viscosity of Newtonian and non Newtonian fluids with only a small amount of sample. The results have high repeatability and can recover samples. Therefore,USP914The method is particularly suitable for the development of biological agents and viscosity measurement.

VROCTechnology meets the requirements of the United States PharmacopeiaUSP914The measurement method.USP914Adopted isRheosenseofV（visocmeter）R（Rheometer）O（On）C（Chip）Chip viscosity rheological integration technology, whether from instrument structure, measurement principle, measurement process, calculation and calibration, onlyVROCChip methodcomply withUSP914Method requirements.

M-VROC II micro sample viscosity analyzer

*The smallest sample viscometer with powerful functions. Test with as low as 10 μ L and repeat the test infinitely. Scanning can be performed at different temperatures and shear rates. The shear rate range is wide, which can simulate the shear rate requirements of various production processes and different application scenarios, such as ultrafiltration, canning, injection, ink-jet and spray, swallowing and other application scenarios.

Technical Specifications

• Minimum sample volume: 10 μ L

• Characterization of Newtonian and Non Newtonian Fluid Solutions

• Wide viscosity range: 2~100000 mPa-s (or cP)

• Temperature: 4 ° C -70 ° C

• Accuracy: up to 2% of the reading

• Repeatable measurement up to 0.5% of the reading

• Compatible chips can be replaced and automatically cleaned through the RheoSense chip cleaning station