Abstract: A method of methylation detection provides a quantitative description of the methylation density in DNA strands. Bisulphite conversion [100] of the DNA strands containing methylated and unmethylated sites creates converted DNA strands with mismatch base pairs. The converted DNA strands are PCR amplified [102], and single strand target DNA strands are magnetically labeled [104] and hybridized [106] with complementary DNA strands immobilized onto a magnetoresistive (MR) sensor array. During hybridization, a binding signal may be recorded. A stringency condition such as temperature or salt concentration is increased [108] to cause the magnetically labeled single strand target DNA strands to be denatured from the complementary DNA strands immobilized onto a magnetoresistive (MR) sensor array.