APPARATUS, METHOD, AND COMPUTER PROGRAM PRODUCT FOR QUANTITATIVE ANALYSIS OF A NUCLEIC ACID AMPLIFICATION REACTION

摘要

The invention provides an apparatus, method, and computer program product for determining a threshold value (e.g., a cycle number or time value) in a nucleic acid amplification reaction. The apparatus is programmed to amplify a nucleic acid sequence and measure, at a plurality of different times during the amplification reaction, at least one signal whose intensity is related to the quantity or concentration of the nucleic acid sequence being amplified. The apparatus stores signal values defining a growth curve for the nucleic acid sequence, determines a first or second derivative of the growth curve, and calculates a threshold cycle number or time value associated with a characteristic of the derivative (e.g., a positive peak of the first derivative, a positive or negative peak of the second derivative, or a zero-crossing of the second derivative). The invention also provides apparatuses, methods, and computer program products for determining an unknown starting quantity or concentration of a nucleic acid sequence in a test sample using quantitative internal controls or using internal standards.