Membrane Filter Plate Research Articles

Experimental Study on the Dust-Cleaning Performance of New Structure Microporous Membrane Filter Plate

On the basis of the existing dust collector structure, this study designed a fan-shaped new structure microporous membrane filter plate (NSMMFP). The pressure distribution law of the NSMMFP can be obtained by measuring the wall surface peak pressure under different injection pressures. The powder attachment experiment was carried out to explore the influence of the dust moisture content on the dust stripping rate (DSR), and a high-speed camera was used to observe the peeling process of the dust. The results show that the peak pressure of each measuring point and the average wall surface peak pressure gradually increase with the injection pressure. The dust stripping quality (DSQ) and rate show an increasing trend as a whole as the injection distance. The DSR of the filter plate shows a downward trend when the dust quality G increases, while DSQ shows the opposite trend. Furthermore, as the dust moisture content increases, the DSQ and DSR gradually decrease. As the dust moisture content increases, the dust attached to the surface of the filter plate is more fragmented and peels from the surface of the filter plate during the dust cleaning process.

Dewatering of brewer’s spent grain using an integrated membrane filter press with vacuum drying capabilities

ABSTRACTBrewer’s spent grain (BSG) is a by-product of the brewing process, rich in fiber, protein and carbohydrates. Its potential application is limited because of high moisture content (80%). This work presents a process for dewatering BSG using two different sets of membrane filter plates in a filter press with vacuum drying: recessive plates with polypropylene membranes and the innovative Rollfit® plates. A final moisture content of 12-15% was obtained in 15 mm-thick filter cakes, using both types of plates. The dewatering cycle included filtration, membrane-squeezing, and vacuum thermal drying using hot water (~90ºC) as heat source.

A cost-effective plate-based sample preparation for antibody N-glycan analysis

During early cell line and process development of therapeutic antibodies, a cost-effective high-throughput approach to characterize the N-linked glycans is highly desired given that a large number of samples need to be analyzed. Using commercially available, low cost 96-well plates, we developed a practical procedure to prepare fluorescently labeled N-linked glycans for both qualitative and quantitative analysis by mass spectrometry (MS) and ultrahigh performance liquid chromatography (UPLC). Antibody samples were continuously denatured, reduced, and deglycosylated in a single 96-well hydrophobic membrane filter plate. Subsequently, released glycans were fluorescently labeled in a collection plate, and cleaned-up using a hydrophilic membrane filter plate. Carried out entirely in ready-to-use 96-well plates with simple buffer systems, this procedure requires less than 90min to finish. We applied the optimized procedure to examine the N-linked glycosylation of trastuzumab and were able to quantify ten major N-linked glycans. The results from different amounts of starting materials (10–200μg) were highly similar and showed the robustness of this procedure. Compared to other methods, this new procedure is simple to implement, economically more affordable, and could be very valuable for early screenings of antibody development.

Selective solid phase extraction of propranolol on multiwell membrane filter plates modified with molecularly imprinted polymer

Molecularly imprinted polymers (MIPs) were synthesized in 24-well glass fiber membrane filter plates to obtain a novel type of solid phase extraction device for the cleanup of propranolol. Sample processing parameters like residence time during sample loading, sample volume, pH, sample solvent, type and amount of washing and elution solvents were investigated and optimized. Important differences from the traditional molecularly imprinted solid phase extraction (MISPE) cartridges have been identified. The MIP modified composite membrane suits well for the sample preparation of low volume biological samples. A protocol has been elaborated for the quantitation of propranolol from urine and plasma samples in the clinically relevant concentration ranges. Preliminary validation results indicate that the composite MIP membrane filter plates offer a viable alternative to existing MISPE cartridges and at the same time have advantages like much easier and faster synthesis method and high-throughput analysis.

Rapid and high-throughput analysis of N-glycans from ovarian cancer serum using a 96-well plate platform

We present a rapid and high-throughput human serum N-glycan preparation technology using 96-well plate-based procedures. The released N-glycans from polyvinylidene fluoride (PVDF) membrane filter plate are subsequently loaded to porous graphitic carbon (PGC) containing a 96-well plate to remove salts and other contaminants without sacrificing accuracy or reproducibility. This robust glycan preparation technology is applied to ovarian cancer diagnosis using 5 μl of patient serum.

Accelerated Development Procedure for Molecularly Imprinted Polymers Using Membrane Filterplates

A novel technique for the synthesis and testing of large numbers of molecularly imprinted polymers is described requiring much less time than the commonly used miniMIP approach. Instead of vials, the polymers are synthesized on the surface of microfiltration membranes in multiwell filterplates. The thin polymeric films enable accelerated template removal. The MIP development procedure is thereby shortened to two days. Performance of the system was demonstrated by creating a combinatorial library of MIPs selective for cimetidine, an antiulcer drug. The polymer composition has been optimized. An experimental design combined with a multivariate analysis (i.e., response surface modeling) was used to minimize the number of experiments in the optimization process. The highest imprinting factor was obtained using a MAA/EDMA/template molar ratio of 3.5:19.5:1.

고효율 열 탈수장치 개발에 관한 연구

A generation rate of sludge in Korea had increased dramatically about 200 % for a decade. A requirement for high efficiency dewatering system being possible to produce the low water content cake have suggested due to the appearanceof commercial and social problems about handing of dewatered cake. The conventional dewatering system with mechanical compression device was not suitable to produce the low water content cake and didn'tcope with lots of requirements. Therefore, this paper was to develop the high efficient filter press with the compressive and heating forces through the heating plate to be built between membrane filter plates. It is possible to produce the low water content cake and improve the dewatering rate, so this equipment positively coped with several types of problems related to the sludge dewatering. The plate heated by heat transfer materials such as steam, hot water and thermo-oil made the sludge make the residual moisture within the cake to discharge easilyand to improve the dewatering efficiency of equipment. The pilot scale experiment with 500㎏ of cake production showed that the dewatering efficiency determined by the final water content and dewatering velocity was improved 30% more than the conventional dewatering equipment.

Fluorescent EIA screening of monoclonal antibodies to cell surface antigens

We have developed a sensitive enzyme immunoassay (EIA) that is useful for detecting antibodies directed against antigenic sites on the surface of mammalian cells. Approximately 100 antigen-bearing cells were trapped in the wells of 96-well Durapore membrane filter plates (Millititer GV plates, Millipore, Bedford, MA). Antibody binding was detected with alkaline phosphatase conjugated goat anti-mouse IgG + IgM. Conjugate alkaline phosphatase activity was detected with a fluorogenic substrate in the presence of levamisole, an inhibitor of endogenous cellular alkaline phosphatase using a Fluoroskan microtiter plate reader (Flow Laboratories). The method permits accurate and reproducible screening of hybridoma supernatants using a minimal number of antigen-bearing cells.

Effects of holding time and temperature on conform numbers in drinking water

Concern has often been expressed about the reliability of coliform counts from drinking water samples held in transit before analysis. Samples collected from a municipal distribution system were split, stored at ambient (22°C) and refrigerator (5°C) temperatures, and analyzed over time for total coliform and heterotrophic bacterial densities. Coliform populations declined significantly at both temperatures after 24 hours. The rate of decline was 2.5 orders of magnitude greater at 22°C than at 5°C. Average losses in 24 hours were 34 percent at 5°C and 87 percent at 22°C. Growth and interference of heterotrophic bacteria with coliform colonies on membrane filter plates were frequently observed for samples held at ambient temperature for 30 hours. A model based on actual coliform recovery was developed to predict initial coliform counts in samples held at various times before examination. For the waters examined, samples held at 22°C for 30 hours with initial coliform counts as high as 100/100 mL could have been reported as satisfactory, thus resulting in inaccurate and misleading information.

Pollution indicator bacteria associated with municipal raw and drinking water supplies

A total of 3819 bacterial cultures isolated from municipal water samples were identified using a combination of Enterotubules and confirmatory media. Frequency distributions for the different genera or groups of bacteria were similar for raw water and drinking water isolations, except for Escherichia organisms which doubled their frequency in raw water. Differences between the membrane filter (MF) and presence-absence (P-A) test with regard to types of organisms isolated were limited to Klebsiella organisms which were preferentially cultured from MF plates. Members of the genus Enterobacter were isolated more than twice as frequently as any of the other coliform genera dealt with in this study. Aeromonas organisms were detected almost as often as such individual genera as Escherichia, Citrobacter, or Klebsiella. Although non-lactose fermenting colonies (false-negatives) of the coliform genera would not be detected by the MF technique, their lack of detection would likely be offset by the Aeromonas colonies (false-positives). At least 25% of the coliform isolates were either anaerogenic or non-lactose fermenters and would therefore go undetected by the most probably number (MPN) technique.