A method for screening of protein candidates, comprising: a) providing fusion proteins, each fusion protein comprising one protein candidate and a protein anchor, wherein the protein anchor is an antibody or antibody fragment comprising the sequence of BSA12 (SEQ ID NO. 2); and b) evaluating the expression levels of the fusion proteins by i. binding the protein anchor to bovine serum albumin on a solid surface; and ii. measuring the amount of bound fusion proteins; or c) evaluating the biophysical properties of the fusion proteins by i. denaturing the fusion proteins; ii. allowing the denatured fusion proteins to refold; iii. filtering sample containing the refolded fusion proteins; iv. binding the protein anchor to bovine serum albumin on a solid surface; v. measuring the amount of bound fusion proteins; and vi. comparing the amount of bound fusion proteins to that obtained in step b); or d) evaluating the binding kinetics of the protein candidates by i. binding the protein anchor to bovine serum albumin on a solid surface; and ii. measuring the binding kinetics of the protein candidates to their target/antigen by allowing the target/antigen to bind to the protein candidates and observing their associations and dissociations; or e) any combination of steps b) to d) above; and f) selecting protein candidates based on expression levels, biophysical properties, and/or binding kinetics, wherein, the protein anchor provides a means of capture of the protein candidates to bovine serum albumin to facilitate evaluation of expression levels, biophysical characteristics and binding kinetics, and wherein the expression levels and/or biophysical properties of the fusion proteins are indicators of the expression levels and/or biophysical properties of the protein candidate alone. a) providing fusion proteins, each fusion protein comprising one protein candidate and a protein anchor, wherein the protein anchor is an antibody or antibody fragment comprising the sequence of BSA12 (SEQ ID NO. 2); and b) evaluating the expression levels of the fusion proteins by i. binding the protein anchor to bovine serum albumin on a solid surface; and ii. measuring the amount of bound fusion proteins; or i. binding the protein anchor to bovine serum albumin on a solid surface; and ii. measuring the amount of bound fusion proteins; or c) evaluating the biophysical properties of the fusion proteins by i. denaturing the fusion proteins; ii. allowing the denatured fusion proteins to refold; iii. filtering sample containing the refolded fusion proteins; iv. binding the protein anchor to bovine serum albumin on a solid surface; v. measuring the amount of bound fusion proteins; and vi. comparing the amount of bound fusion proteins to that obtained in step b); or i. denaturing the fusion proteins; ii. allowing the denatured fusion proteins to refold; iii. filtering sample containing the refolded fusion proteins; iv. binding the protein anchor to bovine serum albumin on a solid surface; v. measuring the amount of bound fusion proteins; and vi. comparing the amount of bound fusion proteins to that obtained in step b); or d) evaluating the binding kinetics of the protein candidates by i. binding the protein anchor to bovine serum albumin on a solid surface; and ii. measuring the binding kinetics of the protein candidates to their target/antigen by allowing the target/antigen to bind to the protein candidates and observing their associations and dissociations; or i. binding the protein anchor to bovine serum albumin on a solid surface; and ii. measuring the binding kinetics of the protein candidates to their target/antigen by allowing the target/antigen to bind to the protein candidates and observing their associations and dissociations; or e) any combination of steps b) to d) above; and f) selecting protein candidates based on expression levels, biophysical properties, and/or binding kinetics,