Re: diode array detector

We use a monochrometer to gather the spectra of a population, but not cell by cell.  I
have used a pmt array in sonolumenscence research, but an array of anything needs to be
calibrated for spatial response and crosstalk.

Jarred

 -------------- Original message ----------------------
From: Howard Shapiro <hms@shapirolab.com>
> 
> Shelley Diamond wrote:
> 
> > Has anyone heard of hanging a diode array detector in a pmt  
> > position so as
> > to detect any wavelength?  I have a group of people here who want to
> > analyze mutations in bacteria on a single cell basis	and collect  
> > emission
> > spectra.  Any clues?	I once heard that Los Alamos people were  
> > looking at
> > these kinds of detectors.  Is there any reason that they wouldn't  
> > work for
> > this kind of detection??
> 
> Diode array detectors will only work for strong fluorescence signals,  
> which you won't be getting from bacteria. A multianode PMT might  
> work, depending on what the fluorescence comes from and how strong it  
> is. When Anne Fu was a graduate student at CalTech with Steve Quake,	
> she built a microfluidic sorter that discriminated between wild type	
> and mutant GFP fluorescence in bacteria, but she just used two PMTs.	
> She couldn't analyze or sort more than a couple of hundred bugs per  
> second, and, to do that in a slow flow system, she needed 10^9 cells/ 
> mL. Doing a multipoint spectrum on bacteria is going to be tough,  
> even in a slow flow system with a multianode PMT.
> 
> -Howard
>