title: Interdigitated microelectrode array-coupled bipolar semiconductor photodiode array (IMEA-PDA) microchip for on-chip electrochemiluminescence detection.
abstract: This paper reports the design, fabrication and testing of a microchip wherein interdigitated microelectrode arrays (IMEA) were integrated with bipolar semiconductor photodiode array (PDA) chip to fabricate a highly compact embodiment for on-chip handling of solutions and electrochemiluminescence (ECL) detection. A 12 x 12 micro array of photodiodes, each coupled with an interdigitated microelectrode array (IMEA), an array of current amplifiers, and a photodiode element-addressing circuit were integrated into a single 2 x 2 cm² IC chip. Each photodiode had dimensions of 300 x 300 μm² and the photodiode-to-photodiode distance was 100 μm. The chip was successfully applied to the on-chip quantification of electro-chemiluminescing probe-labeled single stranded oligonucleotides. The minimum detectable limit at signal/noise ≥ 3 was found to be 5 x 10⁻¹⁴ moles of oligonucleotides with a sample volume as low as 5 microl (i.e., 10 fmole/μl). The attractive features of the developed IMEA-PDA microchip are that a plurality of samples can be analyzed simultaneously using a chip and that for a given sample the data can be averaged from values obtained from multiple, individually addressed pixels. These in turn bring in speed and statistical confidence in analysis. The IMEA-PDA microchip system has the potential to be used as a versatile and highly compact chemical analysis tool for chemical sensing and metrology applications.
authors.affiliation: Research Institute of Pharmaceutical Sciences and College of Pharmacy, Seoul National University, Seoul 151-742, South Korea.
authors.forename: Sukdeb
authors.initials: S
authors.lastname: Pal
authors.forename: Min Jung
authors.initials: MJ
authors.lastname: Kim
authors.forename: Yu Kyung
authors.initials: YK
authors.lastname: Tak
authors.forename: Ho Taik
authors.initials: HT
authors.lastname: Kwon
authors.forename: Joon Myong
authors.initials: JM
authors.lastname: Song
mesh_terms: D004563:Electrochemistry / Q000295:instrumentation*; D056656:Lab-On-A-Chip Devices; D008024:Ligands; D049408:Luminescent Agents / Q000737:chemistry; D008163:Luminescent Measurements / Q000295:instrumentation*; D008839:Microelectrodes; D009841:Oligonucleotides / Q000032:analysis / Q000737:chemistry; D009942:Organometallic Compounds / Q000737:chemistry; D012428:Ruthenium / Q000737:chemistry; D012666:Semiconductors / Q000295:instrumentation*
chemical_list: D008024:Ligands; D049408:Luminescent Agents; D009841:Oligonucleotides; D009942:Organometallic Compounds; D012428:Ruthenium