Cardiac biomarker detection helps in early diagnosis of cardiac syndromes. cost effective sensors that can detect multiple biomolecules will definitely help cardiac patient treatment and prognosis. we are developing smartphone-based disposable, label free, impedimetric biosensors for the detection of two common cardiac biomarkers, myoglobin (myo) and myeloperoxidase (mpo). the device consists of two parts: the sensing substrate and the module for interfacing it with a smartphone. the sensor is fabricated on whatman filter paper coated with a conducting polymer, polyaniline (pani). the polyaniline-coated paper is functionalized with glutaraldehyde, a homo-bi functional crosslinker, prior to the covalent attachment of antibodies specific to each biomarker protein. non-specific active regions of the sensor are blocked by treatment with bovine serum albumin (bsa). conductive silver paste is used to define electrodes for ac impedance measurement on the pani coated filter paper. binding of the target protein (myo or mpo) to the specific antibody changes the impedance between the electrodes; this is detected using ac impedance spectroscopy. the impedance is measured using a frequency response analyzer (fra) with an ac excitation voltage of 100 mv in the frequency range of 100 hz – 1 khz. we can successfully detect myo and mpo in buffer solution within the concentration range of 100 ng/ml – 50 µg/ml. detection limit obtained for these cardiac biomarkers spiked in human serum is 1 µg/ml. further blocking using human serum improves the lower detection limit to 500 ng/ml. the developed biosensor uses inexpensive materials and fabrication techniques, detects cardiac biomarkers in clinically relevant concentrations rapidly (i.e., within 20 minutes), and can be disposed in an environment friendly manner, thus making the sensor suitable for diagnostic applications. the sensitivity can be further improved by a more precisely defined electrode configuration, usage of secondary antibodies tagged with electrically or electrochemically active species, etc. in order to make a handheld, portable point-of-care device, a plug and play module for smartphone is developed to provide a cost and space effective solution. the prepared module acts as a peripheral to the phone and it can be carried in the pocket along with the headphone. a low power and low cost potentiostat is designed in the peripheral, which connects to the audio jack and gets the power from the usb port of the smartphone. the frequency range of the peripheral is limited to the audio range of 10 hz to 10 khz and the maximum duration each frequency signal can be generated is 5 seconds. the onetime buying price of a single unit at research level is approximately inr 1500 (~ usd 20), along with a minimal price for the cartridge i.e., the sensing substrate.