The present invention provides biosensors for detecting cholesterol and OxLDL in blood sample. The present invention relates to a paper-based colorimetric biosensor and an electrochemical biosensor each for detecting cholesterol and OxLDL in blood sample. The biosensors are inexpensive, rapid, simple, portable, diagnostics that incorporate information from multiple biomarkers associated with cardiovascular disease. The biosensors provide diagnostic test results that would place vital health data in the hands of doctors and patients and thus establish a framework for further advances in personalized medicine.