K-Patents has published a new application note on seasonal flu vaccines production. Seasonal flu vaccines production, using ultracentrifugation for viral particle separation, can be considerably improved by using a K-Patents refractometer. The fractionation of viral rich material can be controlled using the K-Patents Pharma refractometer. The different fractions with viral rich and disposable material are separated based on their sucrose density gradients.
The viral vaccines are either produced by inoculating viruses into specific pathogen-free eggs or in animal cell culture based process. The allantoic fluid of these processes is harvested and purified by centrifugation and stabilised with buffer containing sucrose.
The continuous flow ultracentrifugation technique is typically used for producing purified and concentrated virus particles on a large scale. The internal subviral core of the virus is separated and fractionated on the basis of their sedimentation rate and the buoyant sucrose density. The K-Patents Pharma Refractometer PR-23-AC is used for accurate measurements of these sucrose densities.
Ultracentrifugation process consists of six flow channels processing the material flows. The process evolves loading of the density gradient into the rotor which is gradually accelerated making the gradient reorient vertically along the outer rotor wall. Further, the sample fluid is continuously pumped into the rotor. The sample particles sediment radially into the gradient of increasing density. They eventually band (iso-pycnically) in cylindrical zones where the gradient density equals the buoyant density of the particle. Finally, the rotor is decelerated, and the gradient reorients itself to the original position without disturbing the particle bands. The banded particles are unloaded and fractions are collected according to the sucrose density gradients measured by K-Patents Process Refractometer.
The typical measurement system comprises of a Pharma Refractometer PR-23-AC unit and a Pharma Mini Flow Cell PMFC-HSS that allows the sensor connection to the zone ultracentrifuge rotor unloading and fractionation phase. The standard Ethernet communication solution allows for simultaneous data logging and continuous monitoring of the measurement values and diagnostic data from an Indicating transmitter DTR to a computer via an Ethernet connection. The optional Field Communication software program CC-11 provides further communication features such as drawing and monitoring of real-time trend chart on the computer screen, saving the measurement data in PDF format and saving and storing the batch data over a selected period of time.
Ref. 6.01.03 Vaccine Production Process (pdf)