A method of detecting hepatitis C virus infection in a subject comprising: (a) contacting an initial biological sample suspected of containing subject anti-HCV antibodies with first and second NS3h capture peptides and first and second detectably labeled conjugate peptides to generate a mixed biological sample that comprises the initial biological sample, the first and second NS3h capture peptides, and the first and second conjugate peptides, wherein (i) the first NS3h capture peptide comprises an amino acid sequence with at least 90% sequence identity with Domain 1 of an HCV NS3 helicase and is no more than 350 amino acids in length, (ii) the second NS3h capture peptide comprises an amino acid sequence with at least 95% sequence identity with a full-length HCV NS3 helicase having Domains 1, 2, and 3, and (iii) the subject anti-HCV antibodies are not in purified form in the biological sample, b) incubating the mixed biological sample under conditions such that: (i) the first NS3h capture peptide specifically binds at least one of the subject antibodies to form a first capture complex and the first conjugate peptide binds the subject antibody in the first capture complex to form a first detectable complex, and (ii) the second NS3h capture peptide specifically binds at least one of the subject antibodies to form a second capture complex and the second conjugate peptide binds the subject antibody in the second capture complex to form a second detectable complex; c) washing the mixed biological sample to generate a washed sample; and d) detecting the presence of the first and/or second detectable complexes, thereby detecting HCV infection in the subject, wherein the presence of both the first and second NS3h capture peptides in the mixed biological sample extends the dynamic range for qualitatively detecting the subject antibodies compared to only using the first or second NS3h capture peptide. (a) contacting an initial biological sample suspected of containing subject anti-HCV antibodies with first and second NS3h capture peptides and first and second detectably labeled conjugate peptides to generate a mixed biological sample that comprises the initial biological sample, the first and second NS3h capture peptides, and the first and second conjugate peptides, wherein (i) the first NS3h capture peptide comprises an amino acid sequence with at least 90% sequence identity with Domain 1 of an HCV NS3 helicase and is no more than 350 amino acids in length, (ii) the second NS3h capture peptide comprises an amino acid sequence with at least 95% sequence identity with a full-length HCV NS3 helicase having Domains 1, 2, and 3, and (iii) the subject anti-HCV antibodies are not in purified form in the biological sample, (i) the first NS3h capture peptide comprises an amino acid sequence with at least 90% sequence identity with Domain 1 of an HCV NS3 helicase and is no more than 350 amino acids in length, (ii) the second NS3h capture peptide comprises an amino acid sequence with at least 95% sequence identity with a full-length HCV NS3 helicase having Domains 1, 2, and 3, and (iii) the subject anti-HCV antibodies are not in purified form in the biological sample, b) incubating the mixed biological sample under conditions such that: (i) the first NS3h capture peptide specifically binds at least one of the subject antibodies to form a first capture complex and the first conjugate peptide binds the subject antibody in the first capture complex to form a first detectable complex, and (ii) the second NS3h capture peptide specifically binds at least one of the subject antibodies to form a second capture complex and the second conjugate peptide binds the subject antibody in the second capture complex to form a second detectable complex; (i) the first NS3h capture peptide specifically binds at least one of the subject antibodies to form a first capture complex and the first conjugate peptide binds the subject antibody in the first capture complex to form a first detectable complex, and (ii) the second NS3h capture peptide specifically binds at least one of the subject antibodies to form a second capture complex and the second conjugate peptide binds the subject antibody in the second capture complex to form a second detectable complex; c) washing the mixed biological sample to generate a washed sample; and d) detecting the presence of the first and/or second detectable complexes, thereby detecting HCV infection in the subject,