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Articles 271 - 300 of 332

Full-Text Articles in Chemical Engineering

Composite Comprising A Metal Substrate And A Corrosion Protecting Layer, Ravi F. Saraf Jul 1999

Composite Comprising A Metal Substrate And A Corrosion Protecting Layer, Ravi F. Saraf

Department of Chemical and Biomolecular Engineering: Funded Proposals

A composite comprising a metal substrate and as a corrosion protecting layer on at least one major surface of said substrate, a composition comprising a thermoset or thermoplastic polymeric matrix, and a conductive filler component, where said filler component comprises electrically conductive particles.


Method For Providing Discharge Protection Or Shielding, Ravi F. Saraf Jun 1999

Method For Providing Discharge Protection Or Shielding, Ravi F. Saraf

Department of Chemical and Biomolecular Engineering: Funded Proposals

Electrostatic discharge protection and electromagnetic interference shielding is provided by applying to a dielectric substrate a composition comprising a polymeric matrix and a conductive filler component. The conductive filler component comprises electrically conductive metal particles and at least one electrically conducting polymer.


Biodegradation Of Thermoplastic And Hermosetting Polyesters From Z-Protected Glutamic Acid, R M. Tadros, Hossein Noureddini, Delmar C. Timm Jun 1999

Biodegradation Of Thermoplastic And Hermosetting Polyesters From Z-Protected Glutamic Acid, R M. Tadros, Hossein Noureddini, Delmar C. Timm

Papers in Biomolecular Engineering

In a previous article,1 the development and molecular characterization of three polyesters from N-carbobenzyloxy-L-glutamic acid (ZGluOH) were reported. The polymers were a linear, heterochain polyester (ZGluOH and ethylene glycol), a crosslinked heterochain polyester (ZGluOH and diglycidyl ether of 1,4-butanediol), and a crosslinked, heterochain aromatic polyester (ZGluOH and diglycidyl ether of bisphenol A). In this manuscript, results of biodegradation studies are reported. The three polymers hydrolyzed to low molecular weight oligomers similar to the monomers with lipase. When exposed to a mixed culture of micro-organisms, the first two resins degraded to biomass and respiratory gases. The crosslinked heterochain aromatic polyester resisted …


Method Of Coupling Ligands Onto Supports And Products Produced Therefrom , William H. Velander, Anuradha Subramanian May 1999

Method Of Coupling Ligands Onto Supports And Products Produced Therefrom , William H. Velander, Anuradha Subramanian

Department of Chemical and Biomolecular Engineering: Patents

A method is disclosed for coupling a ligand within a porous support. The method involves mixing ligand and porous support under conditions sufficient to suppress coupling conditions of the ligand to the porous support while enhancing the relative rate of diffusion, to the rate of reaction, of the ligand into and within the porous support, and then altering the conditions to enhance rapid coupling of the ligand within the porous support. The alteration from diffusion conditions to coupling conditions involves a change in the reaction solution of pH, ionic strength, temperature, coupling competitor, such that a relatively lower Thiele Modulus …


Method Of Coupling Ligands Onto Supports And Products Produced Therefrom , William H. Velander May 1999

Method Of Coupling Ligands Onto Supports And Products Produced Therefrom , William H. Velander

Department of Chemical and Biomolecular Engineering: Patents

A method is disclosed for coupling a ligand within a porous support. The method involves mixing ligand and porous support under conditions sufficient to suppress coupling conditions of the ligand to the porous support while enhancing the relative rate of diffusion, to the rate of reaction, of the ligand into and within the porous support, and then altering the conditions to enhance rapid coupling of the ligand within the porous support. The alteration from diffusion conditions to coupling conditions involves a change in the reaction solution of pH, ionic strength, temperature, coupling competitor, such that a relatively lower Thiele Modulus …


Direct Chip Attach For Low Alpha Emission Interconnect System, Ravi F. Saraf Apr 1999

Direct Chip Attach For Low Alpha Emission Interconnect System, Ravi F. Saraf

Department of Chemical and Biomolecular Engineering: Patents

An interconnect system that has low alpha particle emission characteristics for use in an electronic device includes a semiconductor chip that has an upper surface and spaced apart electrically resistive bumps positioned on conductive regions of the upper surface, the electrically resistive bumps are made of a composite material of a polymer and metal particles, and a substrate that has conductive regions bonded to the electrically resistive bumps in a bonding process wherein the electrically resistive bumps convert to electrically conductive bumps after the bonding process.


Transgenic Mammals Expressing Human Coagulation Factor Viii , William H. Velander Mar 1999

Transgenic Mammals Expressing Human Coagulation Factor Viii , William H. Velander

Department of Chemical and Biomolecular Engineering: Patents

A non-human transgenic mammalian animal, as described above, contains an exogenous double stranded DNA sequence stably integrated into the genome of the animal, which comprises cis-acting regulatory units operably linked to a DNA sequence encoding human Factor VIII protein and a signal peptide, where the cis-acting regulatory units are active in mammary gland cells and the signal peptide is active in directing newly expressed Factor VIII into the milk of the animal. The promoter may be a milk protein promoter such as for whey acidic protein, casein, lactalbumin, or beta-lactoglobulin promoter. The transgenic mammals are preferably farm animals, for example, …


A Mutant Of Chlamydomonas Reinhardtii With Reduced Rate Of Photorespiration, Kensaku Suzuki, Tarlan G. Mamedov, Toraoyoshi Ikawa Feb 1999

A Mutant Of Chlamydomonas Reinhardtii With Reduced Rate Of Photorespiration, Kensaku Suzuki, Tarlan G. Mamedov, Toraoyoshi Ikawa

Papers in Biochemical Engineering

Photorespiration rates under air-equilibrated conditions (0.04% CO2 and 21% O2) were measured in Chlamydomonas reinhardtii wild-type 2137, a phosphoglycolate-phosphatase-deficient (pgpl) mutant and a suppressor double mutant (7FR2N) derived from the pgpl mutant. In both cells grown under 5% CO2 and adapted air for 24 h in the suppressor double mutant, the maximal rate of photorespiration (phosphoglycolate synthesis) was only about half of that in either the wild type or the pgpl mutant (18-7F) cells. In the progeny, the reduced rate of photorespiration was accompanied by increased photosynthetic affinity for inorganic carbon and the capacity for growth …


Lead Free Conductive Composites For Electrical Interconnections, Ravi F. Saraf Feb 1999

Lead Free Conductive Composites For Electrical Interconnections, Ravi F. Saraf

Department of Chemical and Biomolecular Engineering: Patents

An electrically conductive paste which includes a thermoplastic polymer, a conductive metal powder and an organic solvent system is disclosed. The invention further encompasses an electrically conductive composite which includes the aforementioned thermoplastic and metal, wherein the metal represents at least about 30% by volume, based on the total volume of the composite. The composite is formed from the paste under elevated temperature. The paste is employed in processes which involve electrically connecting electrical and electronic components under process conditions which convert the paste to the composite.


Lead Free Conductive Composites For Electrical Interconnections, Ravi F. Saraf Feb 1999

Lead Free Conductive Composites For Electrical Interconnections, Ravi F. Saraf

Department of Chemical and Biomolecular Engineering: Patents

An electrically conductive paste which includes a thermoplastic polymer, a conductive metal powder and an organic solvent system is disclosed. The invention further encompasses an electrically conductive composite which includes the aforementioned thermoplastic and metal, wherein the metal represents at least about 30% by volume, based on the total volume of the composite. The composite is formed from the paste under elevated temperature. The paste is employed in processes which involve electrically connecting electrical and electronic components under process conditions which convert the paste to the composite.


Lead Free Conductive Composites For Electrical Interconnections, Ravi F. Saraf Feb 1999

Lead Free Conductive Composites For Electrical Interconnections, Ravi F. Saraf

Department of Chemical and Biomolecular Engineering: Patents

An electrically conductive paste which includes a thermoplastic polymer, a conductive metal powder and an organic solvent system is disclosed. The invention further encompasses an electrically conductive composite which includes the aforementioned thermoplastic and metal, wherein the metal represents at least about 30% by volume, based on the total volume of the composite. The composite is formed from the paste under elevated temperature. The paste is employed in processes which involve electrically connecting electrical and electronic components under process conditions which convert the paste to the composite.


Bovine Follicular Dynamics, Oocyte Recovery,And Development Of Oocytes Microinjected With A Green Fluorescent Protein Construct, M S. Chauhan, S Nadir, T L. Bailey, A W. Pryor, S P. Butler, D R. Notter, William H. Velander, F C. Gwazdauskas Jan 1999

Bovine Follicular Dynamics, Oocyte Recovery,And Development Of Oocytes Microinjected With A Green Fluorescent Protein Construct, M S. Chauhan, S Nadir, T L. Bailey, A W. Pryor, S P. Butler, D R. Notter, William H. Velander, F C. Gwazdauskas

Papers in Biotechnology

The present study was carried out to 1) evaluate the viability of in vitro fertilized zygotes after microinjection of DNA, 2) assess the influence of oocyte quality upon the development rate of embryos when injected with DNA, and 3) determine the integration frequency of green fluorescent protein DNA into microinjected embryos. Oocytes were aspirated from ovaries of nine nonlactating Holsteins and were categorized into grades A, B, C, and D. At 16 h after in vitro fertilization, approximately half of the pronuclear stage presumptive zygotes were classified as having 1 pronucleus or 2 pronuclei, and they were microinjected with DNA …


A Red-Dot-Blot Protein Assay Technique In The Low Nanogram Range, Tiilin Marcol, Anuradha Subramanian Jan 1999

A Red-Dot-Blot Protein Assay Technique In The Low Nanogram Range, Tiilin Marcol, Anuradha Subramanian

Papers in Biotechnology

A simple, sensitive, rapid (3 min), and highly reproducible solid-phase assay for the detection of proteins in the low nanogram range (4 ng) is described. The assay is based on differential Pon-ceau S staining of the protein spots on nitrocellulose and quantification of the protein- dye com-plexes on lubricated membranes using a densitometer. The dye solution used for protein stain-ing contained 0.1% Ponceau S in 15% phosphoric acid and 10% ethanol. Proteins were directly spotted onto pre- Ponceau S-stained nitrocellulose membranes, crosslinked with glutaraldehyde, rinsed in NaOH, restained with Ponceau S, and finished by rinsing in acid water at pH …


A Red-Dot-Blot Protein Assay Technique In The Low Nanogram Range, Tiilin Marcol, Anuradha Subramanian Jan 1999

A Red-Dot-Blot Protein Assay Technique In The Low Nanogram Range, Tiilin Marcol, Anuradha Subramanian

Papers in Biotechnology

A simple, sensitive, rapid (3 min), and highly reproducible solid-phase assay for the detection of proteins in the low nanogram range (4 ng) is described. The assay is based on differential Pon-ceau S staining of the protein spots on nitrocellulose and quantification of the protein- dye com-plexes on lubricated membranes using a densitometer. The dye solution used for protein stain-ing contained 0.1% Ponceau S in 15% phosphoric acid and 10% ethanol. Proteins were directly spotted onto pre- Ponceau S-stained nitrocellulose membranes, crosslinked with glutaraldehyde, rinsed in NaOH, restained with Ponceau S, and finished by rinsing in acid water at pH …


Lead-Free Interconnection For Electronic Devices, Ravi F. Saraf Dec 1998

Lead-Free Interconnection For Electronic Devices, Ravi F. Saraf

Department of Chemical and Biomolecular Engineering: Patents

An electronic device that is equipped with a plurality of bonding pads positioned on the device for making electrical interconnections and electrically conductive composite bumps adhered to the bonding pads wherein the bumps are formed of a composite material consisting of a thermoplastic polymer and at least about 30 volume percent of conductive metal particles based on the total volume of the metal particles and the thermoplastic polymer. The present invention is also directed to a method of making electrical interconnections to an electronic device by pressing a plurality of composite bumps of a polymeric based material against a substrate …


Optimization Of Temperature-Glycerol-Ph Conditions For Fed-Batch Fermentation Process For Recombinant Hookworm (Ancylostoma Caninum) Anticoagulant Peptide (Acap-5) Production By Pichia Pastoris, Mehmet İnan, Vijay Chiruvolu, Kent M. Eskridge, George P. Vlasuk, Kenneth Dickerson, Scott Brown, Michael M. Meagher Dec 1998

Optimization Of Temperature-Glycerol-Ph Conditions For Fed-Batch Fermentation Process For Recombinant Hookworm (Ancylostoma Caninum) Anticoagulant Peptide (Acap-5) Production By Pichia Pastoris, Mehmet İnan, Vijay Chiruvolu, Kent M. Eskridge, George P. Vlasuk, Kenneth Dickerson, Scott Brown, Michael M. Meagher

Papers in Biochemical Engineering

This study was undertaken to determine the optimum pH, temperature and glycerol feed rate for the production of recombinant hookworm (Ancylostoma caninum) anticoagulant peptide (rAcAP-5) by Pichia pastoris using response surface methodology (RSM). A central composite design was used as an experimental design for allocation of treatment combinations in three blocks. The variables selected for study were pH, temperature and glycerol feed rate. pH was the most important variable affecting yield, specific yield and specific activity of rAcAP-5. Glycerol feed rate had a significant effect on the specific activity of rAcAP-5 (% of total secreted protein) while temperature …


Entropy Generation In A Rectangular Packed Duct With Wall Heat Flux, Yaşar Demirel, Ramazan Kahraman Sep 1998

Entropy Generation In A Rectangular Packed Duct With Wall Heat Flux, Yaşar Demirel, Ramazan Kahraman

Papers in Thermal Mechanics

The entropy generation due to heat transfer and friction has been calculated for fully developed, forced convection flow in a large rectangular duct, packed with spherical particles, with constant heat fluxes applied to both the top (heated) and bottom (cooled) wall. An approximate analytical expression for the velocity profile developed for packed bed with H/dp > 5 has been used together with the energy equation of fully developed flow to calculate the non isothermal temperature profiles along the flow passage. The velocity profile takes into account the increase in the velocity near the wall due to the higher voidage in this …


Electronic Package Comprising A Substrate And A Semiconductor Device Bonded Thereto, Ravi F. Saraf Jul 1998

Electronic Package Comprising A Substrate And A Semiconductor Device Bonded Thereto, Ravi F. Saraf

Department of Chemical and Biomolecular Engineering: Patents

A composition containing a polymeric matrix and a conductive filler component is provided. The conductive filler component comprises conductive particles and a polymer selected from the group consisting of substituted and unsubstituted polyanilines, substituted and unsubstituted polyparaphenylenevinylenes, substituted and unsubstituted polythiophenes, substituted and unsubstituted polyazines, substituted and unsubstituted polyparaphenylenes, substituted and unsubstituted polyfuranes, substituted and unsubstituted polypyrroles, substituted and unsubstituted polyselenophene, substituted and unsubstituted poly-p-phenylene sulfides and substituted and unsubstituted polyacetylenes, and mixtures thereof, and copolymers thereof. The compositions of the present invention are useful as adhesives for interconnecting a semiconductor chip to a substrate


Electronic Package Comprising A Substrate And A Semiconductor Device Bonded Thereto, Ravi F. Saraf Jul 1998

Electronic Package Comprising A Substrate And A Semiconductor Device Bonded Thereto, Ravi F. Saraf

Department of Chemical and Biomolecular Engineering: Patents

A composition containing a polymeric matrix and a conductive filler component is provided. The conductive filler component comprises conductive particles and a polymer selected from the group consisting of substituted and unsubstituted polyanilines, substituted and unsubstituted polyparaphenylenevinylenes, substituted and unsubstituted polythiophenes, substituted and unsubstituted polyazines, substituted and unsubstituted polyparaphenylenes, substituted and unsubstituted polyfuranes, substituted and unsubstituted polypyrroles, substituted and unsubstituted polyselenophene, substituted and unsubstituted poly-p-phenylene sulfides and substituted and unsubstituted polyacetylenes, and mixtures thereof, and copolymers thereof. The compositions of the present invention are useful as adhesives for interconnecting a semiconductor chip to a substrate


Direct Chip Attachment (Dca) With Electrically Conductive Adhesives, Ravi F. Saraf May 1998

Direct Chip Attachment (Dca) With Electrically Conductive Adhesives, Ravi F. Saraf

Department of Chemical and Biomolecular Engineering: Patents

A simple process for card assembly by Direct Chip Attachment (DCA) uses electrically conductive adhesives. Two methods create the same intermediate wafer product with a layer of insulative thermoplastic and conductive thermoplastic bumps. After sawing or dicing the wafer to form the chips, the chips are adhered to chip carriers with conductive pads which match the conductive thermoplastic bumps, using heat and pressure. Chips may be easily removed and replaced using heat.


Direct Chip Attachment (Dca) With Electrically Conductive Adhesives, Ravi F. Saraf May 1998

Direct Chip Attachment (Dca) With Electrically Conductive Adhesives, Ravi F. Saraf

Department of Chemical and Biomolecular Engineering: Patents

A simple process for card assembly by Direct Chip Attachment (DCA) uses electrically conductive adhesives. Two methods create the same intermediate wafer product with a layer of insulative thermoplastic and conductive thermoplastic bumps. After sawing or dicing the wafer to form the chips, the chips are adhered to chip carriers with conductive pads which match the conductive thermoplastic bumps, using heat and pressure. Chips may be easily removed and replaced using heat.


Direct Chip Attachment (Dca) With Electrically Conductive Adhesives, Ravi F. Saraf May 1998

Direct Chip Attachment (Dca) With Electrically Conductive Adhesives, Ravi F. Saraf

Department of Chemical and Biomolecular Engineering: Patents

A simple process for card assembly by Direct Chip Attachment (DCA) uses electrically conductive adhesives. Two methods create the same intermediate wafer product with a layer of insulative thermoplastic and conductive thermoplastic bumps. After sawing or dicing the wafer to form the chips, the chips are adhered to chip carriers with conductive pads which match the conductive thermoplastic bumps, using heat and pressure. Chips may be easily removed and replaced using heat.


Analysis Of Combustion-Driven Acoustics, Leonie Boshoff-Mostert, Hendrik J. Viljoen May 1998

Analysis Of Combustion-Driven Acoustics, Leonie Boshoff-Mostert, Hendrik J. Viljoen

Papers in Reaction Kinetics

Combustion-driven acoustic oscillations are investigated by performing a onedimensional stability analysis of a burner-stabilized premixed flame. In contrast to other investigators, no initial acoustic wave is assumed in the analysis; the downstream acoustic field results from flame instability. Two models are considered: the thermodiffusive model (uncoupled model) and the fully coupled thermodiffusive-hydrodynamic model. The fully coupled problem exhibits instability at a much lower critical Lewis number than the uncoupled problem.


A Study Of Piezoelectric Orthorhombic Ta2O5, B. R. Jooste, Hendrik J. Viljoen Feb 1998

A Study Of Piezoelectric Orthorhombic Ta2O5, B. R. Jooste, Hendrik J. Viljoen

Hendrik J. Viljoen Publications

In 1985 it was first reported that monoclinic Ta2O5 has piezoelectric properties comparable to ZnO. In this work we report on the deposition, characterization, and qualitative assessment of the piezoelectric behavior of orthorhombic Ta2O5. Reactive magnetron sputtering was used to deposit thin films of Ta2O5 onto substrates of 316L stainless steel. Without substrate heating the crystallinity was poor. A rapid thermal anneal improved the crystallinity. The orthorhombic phase was dominantly present on all substrates. The piezoelectric property was qualitatively assessed, including a high temperature test at 650 °C.


Composition Containing A Polymer And Conductive Filler And Use Thereof, Ravi F. Saraf Dec 1997

Composition Containing A Polymer And Conductive Filler And Use Thereof, Ravi F. Saraf

Department of Chemical and Biomolecular Engineering: Patents

A composition containing a polymeric matrix and a conductive filler component is provided. The conductive filler component comprises conductive particles and a polymer selected from the group consisting of substituted and unsubstituted polyanilines, substituted and unsubstituted polyparaphenylenevinylenes, substituted and unsubstituted polythiophenes, substituted and unsubstituted polyazines, substituted and unsubstituted polyparaphenylenes, substituted and unsubstituted polyfuranes, substituted and unsubstituted polypyrroles, substituted and unsubstituted polyselenophene, substituted and unsubstituted poly-p-phenylene sulfides and substiututed and unsubstituted polyacetylenes, and mixtures thereof, and copolymers thereof. Compositions of the present invention are useful as corrosion protecting layers for metal substrates, for electrostatic discharge protection, electromagnetic interference shielding, and as …


Crossflow Microfiltration Of Recombinant Escherichia Coli Lysates After High Pressure Homogenization, Stuart M. Bailey, Michael M. Meagher Nov 1997

Crossflow Microfiltration Of Recombinant Escherichia Coli Lysates After High Pressure Homogenization, Stuart M. Bailey, Michael M. Meagher

Papers in Biotechnology

Abstract: Crossflow membrane filtration was used to process recombinant Escherichia coli cell lysates containing protein inclusion bodies after high pressure homogenization. The number of passes through the high pressure homogenizer changed the viscosities and average particle sizes of the cell lysates. The different cell lysates were processed with a hollow fiber unit containing microfiltration membranes and a plate and frame unit with either ultrafiltration or microfiltration membranes. There were differences in permeate flux and protein transmission for the various membranes with the best performing membranes giving permeate fluxes greater than 60 L m−2 h−1 and protein transmissions greater than 90%. …


Plasticized, Antiplasticized And Crystalline Conducting Polymers, Ravi F. Saraf Jul 1997

Plasticized, Antiplasticized And Crystalline Conducting Polymers, Ravi F. Saraf

Department of Chemical and Biomolecular Engineering: Funded Proposals

Materials containing precursors to electrically conductive polymers and electrically conductive polymers are described which have a high degree of crystallinity. The high degree of crystallinity is achieved by preparing the materials under conditions which provide a high degree of mobility to the polymer molecules permitting them to associate with one another to form a crystalline state. High levels of electrical conductivity are achieved in in the electrically conductive materials without stretch orienting the material. The enhanced electrical conductivity is isotropic as compared to a stretch oriented film which has isotropic electrical conductivity.


Expression Of Human Protein C In Mammary Tissue Of Transgenic Mammals , William H. Velander Dec 1996

Expression Of Human Protein C In Mammary Tissue Of Transgenic Mammals , William H. Velander

Department of Chemical and Biomolecular Engineering: Patents

Recombinant protein C characterized by a high percentage of active protein can be obtained in the milk of transgenic mammals that incorporate DNAs according to the present invention. Transgenic mammals of the present invention are produced by introducing into developing embryos DNA that encodes protein C, such that the DNA is stably incorporated in the DNA of germ line cells of the mature mammals and inherited in normal, mendelian fashion.


Affinity Purification Of Biologically Active Andinactive Forms Of Recombinant Human Protein C Produced In Porcine Mammary Gland, Kevin E. Van Cott, Barry Williams Department Of Chemical Engineering,Virginia Tech University, Blacksburg, Va 24061, Usa, William H. Velander, Francis C. Gwazdauskas, Tim Lee Jerome Holland Laboratory, American Red Cross, Rockville, Md 20855, Usa, Henryk Lubon, William N. Drohan Sep 1996

Affinity Purification Of Biologically Active Andinactive Forms Of Recombinant Human Protein C Produced In Porcine Mammary Gland, Kevin E. Van Cott, Barry Williams Department Of Chemical Engineering,Virginia Tech University, Blacksburg, Va 24061, Usa, William H. Velander, Francis C. Gwazdauskas, Tim Lee Jerome Holland Laboratory, American Red Cross, Rockville, Md 20855, Usa, Henryk Lubon, William N. Drohan

Papers in Biotechnology

Recombinant human protein C (rhPC) secreted in the milk of transgenic pigs was studied. 'Ikansgenes having different regulatory elements of the murine milk protein, whey acidic protein, were used with cDNA and genomic human protein C (hPC) DNA sequences to obtain lower and higher expressing animals. The cDNA pigs had a range of expression of about 0.1-0.5 g/l milk. Two different genomic hPC pig lines have expressed 0.3 and 1-2 g/l, respectively. The rhPC was first purified at yields greater than 60 per cent using a monoclonal antibody (mAb) to the activation site on the heavy chain of hPC. Subsequent …


Effect Of Antibody Orientation On Immunosorbent, Anuradha Subramanian, William H. Velander Sep 1996

Effect Of Antibody Orientation On Immunosorbent, Anuradha Subramanian, William H. Velander

Papers in Biotechnology

The impact of antibody orientation on immunosorbent efficiency was quantitatively assessed. A pH-dependent murine monoclonal antibody (Mab) against human protein C (hPC), recombinant hPC (rhPC) and two different immobilization chemistries and matrices were used as model systems. The lysyl groups of the rhPC were covalently modified with an acetic acid ester of N-hydroxysuccinimide and this modified rhPC was used as a Fab masking agent (FMA). The FMA was used to mask the antigen bind-ing regions (Fab) of the Mab prior to and during covalent immobilization. Thereafter, the residual active sites of the support were in-activated and the FMA was removed. …