BEH.462/3. 962J Molecular Principles of Biomaterials Spring 2003 Lecture 20: Cell-and tissue-based biosensors Last tir detection methods Surface plasmon resonance biosensors Today cell- and tissue-based sensors Primary transducers and biosensor design with living cells microphysiometer Reading J.J. Pancrazio et al., Development and application of cell-based biosensors, Ann Biomed.Eng27,697-711(1999) Cell-based biosensors 1-6 General concepts Why cell-based biosensors? o Known ultrasensitivity of cells Olfactory neurons respond to single odorant molecules Retinal neurons triggered by single photons T cells triggered by single antigenic peptides DIC/ura over Calcium signalling Potential for single molecule sensitivity TIme relative to Ca+ signal (ml retinal neurons triggered by PMrG PE fuorescence single photons In T/APC Interface ifactory neurons detect single odorant molecules T cell recognition of foreign peptide(shown at night 5 um -Cellular machinery maintains physiological status of receptors involved in detection 30%100 Complex @valuation@f 6 aaen 03040506070 Error! (Irvine et al. 2002) o Ability to ' integrate cellular or tissue response to compounds Detect functionality of compound in addition to its chemical presence i.e. tell the difference between a dead and live virus Lecture 20-Biosensors 1 of 8BEH.462/3.962J Molecular Principles of Biomaterials Spring 2003 Lecture 20 – Biosensors 1 of 8 Lecture 20: Cell- and Tissue-based biosensors Last time: detection methods Surface plasmon resonance biosensors Today: cell- and tissue-based sensors Primary transducers and biosensor design with living cells microphysiometer Reading: J.J. Pancrazio et al., ‘Development and application of cell-based biosensors,’ Ann. Biomed. Eng. 27, 697-711 (1999) Cell-based biosensors1-6 General concepts ƒ Why cell-based biosensors? o Known ultrasensitivity of cells: ƒ Olfactory neurons respond to single odorant molecules ƒ Retinal neurons triggered by single photons ƒ T cells triggered by single antigenic peptides7 Error! (Irvine et al. 2002) Calcium signaling ¥Potential for single￾molecule sensitivity -retinal neurons triggered by single photons -olfactory neurons detect single odorant molecules -T cell recognition of foreign peptide (shown at right) ¥Cellular machinery maintains physiological status of receptors involved in detection ¥Complex ÔevaluationÕ of agents o Ability to ‘integrate’ cellular or tissue response to compounds ƒ Detect functionality of compound in addition to its chemical presence • i.e. tell the difference between a dead and live virus