From OpenWetWare
Jump to navigationJump to search
Center for Advanced Sensor Technology
Center for Advanced Sensor Technology

<html> <head>

<body bgcolor="#00FF00" marginwidth="0" marginheight="0" leftmargin="0" topmargin="0">

<table width="98%" border="4" cellspacing="1" cellpadding="4">

   <td width="100%" bgcolor="@@(NavHeaderColor)@@"><div align="center"><font color="#FF0000" size="+2">


   <td bgcolor="@@(NavBackgroundColor)@@"> 
     <table width="100%" border="1" cellspacing="1" cellpadding="2">
         <td align="center" width="20%"><a href="/wiki/CAST:Home" title="Home">HOME</a></td>
         <td align="center" width="20%"><a href="/wiki/CASTlab:Members" title=Members">MEMBERS</a></td>
         <td align="center" width="20%"><a href="/wiki/CASTlab:Calendar" title=Calendar">CALENDAR</a></td>
         <td align="center" width="20%"><a href="/wiki/CASTlab:Internal" title=Internal">INTERNAL</a></td>
         <td align="center" width="20%"><a href="/wiki/CASTlab:Research" title=Research>RESEARCH</a></td>
         <td align="center" width="20%"><a href="/wiki/CASTlab:External" title=External>RELATED LINKS</a></td>
         <td align="center" width="20%"><a href="/wiki/CASTlab:Contacts" title=Contacts>CONTACTS</a></td>


</body> </html>

Kostov Y., Rao. G. (1999) Simple low-cost device for fluorescence ratiometric measurements. Rev. Sci. Instr., 70, 4466-4470.


An all-solid-state, low-cost device for fluorescent wavelength-ratiometric detection is described. Ultrabright light-emitting diodes were used as light sources. This allowed electronic modulation of the light, simple optical configuration, and miniaturization of the instrument. Narrow-bandpass interference filters were used for wavelength separation. Detection was accomplished by high-sensitivity, large-surface PIN photodiodes. An integrating double-ramp technique with fixed upper and lower thresholds was employed for conversion of the light intensities into time intervals. The duty ratio of the output signal was a function of the fluorescence intensity ratio. Additionally, the concentration of the fluorophore could be measured. The device could be easily designed as a battery-operated version. It could be used for a variety of ratiometric fluorescence measurements. © 1999 American Institute of Physics. [S0034-6748~99!01412-4]

Return to Yordan Kostov Publication
Return to Center for Advanced Sensor Technology Homepage