Bioprocess chromatography

Toyopearl HW size exclusion chromatography resins are macroporous packings for bioprocessing chromatography. They are applicable for process-scale... 

Merck KGaA PC-SRG-Bioprocess Chromatography Frankfurter Str. 250 64293 Darmstadt Germany... 

There are several methods to monitor the off-gas analysis. Online gas chromatography is commonly used. The daily operation for inlet and outlet gases is balanced to project growth in the bioprocess. High operating cost is the disadvantage of the online system. 

Fermentation broths are complex, aqueous mixtures of cells, comprising soluble extracellular, intracellular products and any unconverted substrate or unconvertible components. Recovery and extraction of product is important in bioprocess engineering. In particular separation is a useful technique it depends on product, its solubility, size of the process, and product value. Purification of high-value pharmaceutical products using chromatography such as hormones, antibody and enzymes is expensive and difficult to scale up.1 Tire necessary steps to follow a specific process depend on the nature of the product and the characteristics of the fermentation broth. There are a few steps for product recovery the following processes are discussed, which are considered as an alternative for product recovery from fermentation broth. 

Instrumentation. A Pharmacia BioPilot Column Chromatography system was used to perform large-scale size exclusion chromatography (SEC) with an 11.3 x 90 cm BioProcess column packed with Sephacryl S-200 HR gel. High performance size exclusion (HPSEC) and ion exchange chromatography (HPIEC) were conducted with Pharmacia Superose 6 and 12 (HR 10/30) and Mono-Q (HR 5/5) columns respectively, equipped with Beckman model 520 system controller and Beckman model HOB HPLC pumps. 

When planning an industrial-scale bioprocess, the main requirement is to scale up each of the process steps. As the principles of the unit operations used in these downstream processes have been outlined in previous chapters, at this point we discuss only examples of practical applications and scaling-up methods of two unit operations that are frequently used in downstream processes (i) cell separation by filtration and microfiltration and (ii) chromatography for fine purification of the target products. 

In the downstream processing of bioprocesses, fixed-bed adsorbers are used extensively both for the recovery of a target and for the removal of contaminants. Moreover, their performance can be estimated from the breakthrough curve, as stated in Chapter 11. The break time tg is given by Equation 11.13, and the extent of the adsorption capacity of the fixed bed utilized at the break point and loss of adsorbate can be calculated from the break time and the adsorption equilibrium. Affinity chromatography, as weii as some ion-exchange chromatography, are operated as specific adsorption and desorption steps, and the overall performance is affected by the column capacity available at the break point and the total operation time. 

Fig. 20. Schematic design of linking a chromatograph on-line to bioprocesses. In principle, the design is almost identical to an FIA system. This is why FIA is often characterized as chromatography without a column. However, degassing of the sample is essential, in particular, when no internal standard is added (as in this sketch). In addition, the technical designs of injection valves differ and the injector to a gas chromatograph is heated to 200 or 250°C which means it needs, therefore, a special construction...

Specific liquid chromatography methodologies and resins have been especially developed for the purpose this is a peculiar situation in the discipline of downstream bioprocessing. Today monoclonal antibodies and more largely immunoglobulins with all their derivatives represent by far the largest class of produced and purified protein in number and mass. 

Coffman, J. L., and Boschetti, E. (1998). Enhanced diffusion chromatography and related sorbents for biopurification. In Bioseparation and Bioprocessing, (G. Subramanian, ed.), pp. 157-198. Wiley-VCH Verlag, Weinheim,... 

Kelly, M. (1991). Measurement and control in process scale liquid chromatography. In Measurement and Control in Bioprocessing (K. G. Carr-Brion, ed.), Chapter 7, pp. 191-219. Elsevier Applied Science, Amsterdam. 

In any case, both biosensors and biosensing devices have been coupled to microdialysis and are considered among the non-separation-based methods [83]. The drawback of biosensing approaches is that they are usually able to measure just one analyte at a time, in contrast with separation-based methods such as chromatography and electrophoresis, which allow the detection of several analytes. However, if the primary interest is not the identification of unknown compounds, but, for example, the monitoring of variations in a single metabolite or drug, the optimization of therapeutic responses, or the control of a bioprocess via a marker analyte, the use of a specific sensor, which can be employed in a continuous manner, can provide useful information, and can also help to avoid the analysis of hundreds of samples or to reduce the number of animals necessary for a study. 

Off -line control by local equipment also here the analysis is made on a sample, which is taken out from the process, but the response time can be much lesser, which ensure more reliable adjustments on the process. The advantage compared to the distance control is obvious. The analysis methods can be expensive and complicated, but it can be as simple as thin layer chromatography (TLC) [22, 23], Chromatographic methods such as HPLC and GC have been commonly used as off line methods for bioprocess monitoring [24, 25] and HPLC is described in section 2.5. 

HPLC-UV diode-array detection (DAD) or HPLC-MS techniques take advantage of chromatography as a separation method and DAD or MS as identification and/or quantification methods. Both DAD and MS can rapidly provide on-line UV and MS information for each individual peak in a chromatogram. In most cases, the identification of the peaks can be made directly on-line by comparison with literature data or with standard compounds. However, when no standard compounds are available, the rapid preliminary identification process becomes significantly more complex. The general identification problem in bioprocess monitoring described below exists in all cases when a new biotechnological process is initiated and when the product is not available as a reference substance. 

Zander, A., Sellergren, B., Renner, T., Findlay. P.H. and Swietlow. A. (1997) Chromatographic Society Recent Developments in Affinity Chromatography -Affinity Bioprocessing and Molecular Imprints, Cambridge, July 1-3. 

Bai Y, Glatz CE (2003) Bioprocess considerations for expanded-bed chromatography of cmde canola extract sample preparation and adsorbent reuse. Biotechnol Bioeng 81 775-782. 

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