I was thinking that sooner or later we'll need to build a spectrophotometer
(I checked prices on ebay but it's too expensive for us, around £300 and
don't know actually if they work properly). A spectrophotometer is used to
measure the concentration of products in a solution (bacteria, DNA, etc)
and it is going to be useful, for example, to standardise the quality of
our competent cells.
There are not so many resources for a DIY one but I found some interesting
links (check especially the last one, quite funny):
> I was thinking that sooner or later we'll need to build a
> spectrophotometer (I checked prices on ebay but it's too expensive for us,
> around £300 and don't know actually if they work properly). A
> spectrophotometer is used to measure the concentration of products in a
> solution (bacteria, DNA, etc) and it is going to be useful, for example, to
> standardise the quality of our competent cells.
> There are not so many resources for a DIY one but I found some interesting
> links (check especially the last one, quite funny):
We have some of the parts for some of these already. I have a couple of
phototransistors, (one is already connected up and has tape around the
outside to cut out stray light) in my box, there are loads of LEDS in the
hackspace one or two Arduino boards if you are free come in and we'll start
building one
On Thu, Oct 18, 2012 at 1:39 PM, Tommaso Vannocci <ktomt...@gmail.com>wrote:
> On 18 October 2012 13:31, Tommaso Vannocci <ktomt...@gmail.com> wrote:
>> Hi,
>> I was thinking that sooner or later we'll need to build a
>> spectrophotometer (I checked prices on ebay but it's too expensive for us,
>> around £300 and don't know actually if they work properly). A
>> spectrophotometer is used to measure the concentration of products in a
>> solution (bacteria, DNA, etc) and it is going to be useful, for example, to
>> standardise the quality of our competent cells.
>> There are not so many resources for a DIY one but I found some
>> interesting links (check especially the last one, quite funny):
Actually, the phototransistors I have are, according to their specs, most
sensitive in the green part of the spectrum so this might be a problem but
we can probably work round this.
On Thu, Oct 18, 2012 at 4:00 PM, simon rose
<excaliburor...@googlemail.com>wrote:
> We have some of the parts for some of these already. I have a couple of
> phototransistors, (one is already connected up and has tape around the
> outside to cut out stray light) in my box, there are loads of LEDS in the
> hackspace one or two Arduino boards if you are free come in and we'll start
> building one
> On Thu, Oct 18, 2012 at 1:39 PM, Tommaso Vannocci <ktomt...@gmail.com>wrote:
>> On 18 October 2012 13:31, Tommaso Vannocci <ktomt...@gmail.com> wrote:
>>> Hi,
>>> I was thinking that sooner or later we'll need to build a
>>> spectrophotometer (I checked prices on ebay but it's too expensive for us,
>>> around £300 and don't know actually if they work properly). A
>>> spectrophotometer is used to measure the concentration of products in a
>>> solution (bacteria, DNA, etc) and it is going to be useful, for example, to
>>> standardise the quality of our competent cells.
>>> There are not so many resources for a DIY one but I found some
>>> interesting links (check especially the last one, quite funny):
Not free today, sorry but really happy to help building it in the future...
though you'll have to teach me, I'm not an expert of electronics.
For monitoring bacteria cultures we'll need to record absorbances at 600
nm, I think it's the colour yellow.
For DNA it's a bit more complicated: we need something to detect at 260 nm,
maybe not possible at the moment.
On 18 October 2012 16:00, simon rose <excaliburor...@googlemail.com> wrote:
> We have some of the parts for some of these already. I have a couple of
> phototransistors, (one is already connected up and has tape around the
> outside to cut out stray light) in my box, there are loads of LEDS in the
> hackspace one or two Arduino boards if you are free come in and we'll start
> building one
> On Thu, Oct 18, 2012 at 1:39 PM, Tommaso Vannocci <ktomt...@gmail.com>wrote:
>> On 18 October 2012 13:31, Tommaso Vannocci <ktomt...@gmail.com> wrote:
>>> Hi,
>>> I was thinking that sooner or later we'll need to build a
>>> spectrophotometer (I checked prices on ebay but it's too expensive for us,
>>> around £300 and don't know actually if they work properly). A
>>> spectrophotometer is used to measure the concentration of products in a
>>> solution (bacteria, DNA, etc) and it is going to be useful, for example, to
>>> standardise the quality of our competent cells.
>>> There are not so many resources for a DIY one but I found some
>>> interesting links (check especially the last one, quite funny):
> Not free today, sorry but really happy to help building it in the
> future... though you'll have to teach me, I'm not an expert of electronics.
> For monitoring bacteria cultures we'll need to record absorbances at 600
> nm, I think it's the colour yellow.
> For DNA it's a bit more complicated: we need something to detect at 260
> nm, maybe not possible at the moment.
> On 18 October 2012 16:00, simon rose <excaliburor...@googlemail.com>wrote:
>> We have some of the parts for some of these already. I have a couple of
>> phototransistors, (one is already connected up and has tape around the
>> outside to cut out stray light) in my box, there are loads of LEDS in the
>> hackspace one or two Arduino boards if you are free come in and we'll start
>> building one
>> On Thu, Oct 18, 2012 at 1:39 PM, Tommaso Vannocci <ktomt...@gmail.com>wrote:
>>> On 18 October 2012 13:31, Tommaso Vannocci <ktomt...@gmail.com> wrote:
>>>> Hi,
>>>> I was thinking that sooner or later we'll need to build a
>>>> spectrophotometer (I checked prices on ebay but it's too expensive for us,
>>>> around £300 and don't know actually if they work properly). A
>>>> spectrophotometer is used to measure the concentration of products in a
>>>> solution (bacteria, DNA, etc) and it is going to be useful, for example, to
>>>> standardise the quality of our competent cells.
>>>> There are not so many resources for a DIY one but I found some
>>>> interesting links (check especially the last one, quite funny):
> 260nm is *well* into the UV dunno if they'll work at that short a
> wavelength. Have to read up on this
> On Thu, Oct 18, 2012 at 4:13 PM, Tommaso Vannocci <ktomt...@gmail.com>wrote:
>> Not free today, sorry but really happy to help building it in the
>> future... though you'll have to teach me, I'm not an expert of electronics.
>> For monitoring bacteria cultures we'll need to record absorbances at 600
>> nm, I think it's the colour yellow.
>> For DNA it's a bit more complicated: we need something to detect at 260
>> nm, maybe not possible at the moment.
>> On 18 October 2012 16:00, simon rose <excaliburor...@googlemail.com>wrote:
>>> We have some of the parts for some of these already. I have a couple of
>>> phototransistors, (one is already connected up and has tape around the
>>> outside to cut out stray light) in my box, there are loads of LEDS in the
>>> hackspace one or two Arduino boards if you are free come in and we'll start
>>> building one
>>> On Thu, Oct 18, 2012 at 1:39 PM, Tommaso Vannocci <ktomt...@gmail.com>wrote:
>>>> On 18 October 2012 13:31, Tommaso Vannocci <ktomt...@gmail.com> wrote:
>>>>> Hi,
>>>>> I was thinking that sooner or later we'll need to build a
>>>>> spectrophotometer (I checked prices on ebay but it's too expensive for us,
>>>>> around £300 and don't know actually if they work properly). A
>>>>> spectrophotometer is used to measure the concentration of products in a
>>>>> solution (bacteria, DNA, etc) and it is going to be useful, for example, to
>>>>> standardise the quality of our competent cells.
>>>>> There are not so many resources for a DIY one but I found some
>>>>> interesting links (check especially the last one, quite funny):
> link to a nice diagram of the absorbance at 650 nm for bacteria
you wouldn't need a spectrometer for that, just a cheap 650nm LED and a suitably
linear photodetector. And a processor to do the calibration and tedious monitoring
of the absorption for several hours so that the result is ready when you get back
from the pub :)
Thanks for the input Nigel!
Well, I'm not an expert in electronics therefore I do not know much about
suitable photodetector but we need this instrument not to monitor bacterial
growth for several hours. We need to measure with good accuracy the cell
density on the spot and to distinguish clearly between a 0.6 and 0.8 Abs at
600 nm (or 650 nm if 600 is not possible). If I'm correct this requires
some accuracy. In my experience also the most simple of the instruments
that I used at work were based on this schematics:
[image: Inline images 1]
On 24 October 2012 22:52, Nigel Worsley <nig...@googlemail.com> wrote:
> link to a nice diagram of the absorbance at 650 nm for bacteria
> you wouldn't need a spectrometer for that, just a cheap 650nm LED and a
> suitably
> linear photodetector. And a processor to do the calibration and tedious
> monitoring
> of the absorption for several hours so that the result is ready when you
> get back
> from the pub :)
> Thanks for the input Nigel!
> Well, I'm not an expert in electronics therefore I do not know much about
> suitable photodetector but we need this instrument not to monitor bacterial
> growth for several hours. We need to measure with good accuracy the cell
> density on the spot and to distinguish clearly between a 0.6 and 0.8 Abs at
> 600 nm (or 650 nm if 600 is not possible). If I'm correct this requires
> some accuracy. In my experience also the most simple of the instruments
> that I used at work were based on this schematics:
> [image: Inline images 1]
> On 24 October 2012 22:52, Nigel Worsley <nig...@googlemail.com> wrote:
>> link to a nice diagram of the absorbance at 650 nm for bacteria
>> you wouldn't need a spectrometer for that, just a cheap 650nm LED and a
>> suitably
>> linear photodetector. And a processor to do the calibration and tedious
>> monitoring
>> of the absorption for several hours so that the result is ready when you
>> get back
>> from the pub :)
> An arduino spectrometer. They had a form on the website to apply to be a beta tester, so I applied.
> On 25 October 2012 10:34, Tommaso Vannocci <ktomt...@gmail.com> wrote:
> Thanks for the input Nigel! > Well, I'm not an expert in electronics therefore I do not know much about suitable photodetector but we need this instrument not to monitor bacterial growth for several hours. We need to measure with good accuracy the cell density on the spot and to distinguish clearly between a 0.6 and 0.8 Abs at 600 nm (or 650 nm if 600 is not possible). If I'm correct this requires some accuracy. In my experience also the most simple of the instruments that I used at work were based on this schematics:
> <image.jpeg>
> On 24 October 2012 22:52, Nigel Worsley <nig...@googlemail.com> wrote:
> link to a nice diagram of the absorbance at 650 nm for bacteria
> you wouldn't need a spectrometer for that, just a cheap 650nm LED and a suitably
> linear photodetector. And a processor to do the calibration and tedious monitoring
> of the absorption for several hours so that the result is ready when you get back
> from the pub :)
Hi Martin,
thanks for the offer. We have some peculiar requirements about wavelengths
and such but we'd love to see what the Public Lab are up to. I noticed they
have nice projects to test their spectrometer and I think it would be cool
also for us to help them out with the testing.
I'd like to speak about it more in details, are you around this wednesday?
Tom
On 7 December 2012 21:24, Martin Dittus <deks...@gmail.com> wrote:
> > An arduino spectrometer. They had a form on the website to apply to be a
> beta tester, so I applied.
> > On 25 October 2012 10:34, Tommaso Vannocci <ktomt...@gmail.com> wrote:
> > Thanks for the input Nigel!
> > Well, I'm not an expert in electronics therefore I do not know much
> about suitable photodetector but we need this instrument not to monitor
> bacterial growth for several hours. We need to measure with good accuracy
> the cell density on the spot and to distinguish clearly between a 0.6 and
> 0.8 Abs at 600 nm (or 650 nm if 600 is not possible). If I'm correct this
> requires some accuracy. In my experience also the most simple of the
> instruments that I used at work were based on this schematics:
> > <image.jpeg>
> > On 24 October 2012 22:52, Nigel Worsley <nig...@googlemail.com> wrote:
> > link to a nice diagram of the absorbance at 650 nm for bacteria
> > you wouldn't need a spectrometer for that, just a cheap 650nm LED and a
> suitably
> > linear photodetector. And a processor to do the calibration and tedious
> monitoring
> > of the absorption for several hours so that the result is ready when you
> get back
> > from the pub :)
Unfortunately I likely won't be there, and I'm also not the right person to talk to if you want to discuss their projects; I simply happen to have a contact there who we could use to find the creators of particular projects.
> Hi Martin, > thanks for the offer. We have some peculiar requirements about wavelengths and such but we'd love to see what the Public Lab are up to. I noticed they have nice projects to test their spectrometer and I think it would be cool also for us to help them out with the testing. > I'd like to speak about it more in details, are you around this wednesday?
> Tom
> On 7 December 2012 21:24, Martin Dittus <deks...@gmail.com> wrote:
> Just happened across your discussion about making your own spectrometer.
> > An arduino spectrometer. They had a form on the website to apply to be a beta tester, so I applied.
> > On 25 October 2012 10:34, Tommaso Vannocci <ktomt...@gmail.com> wrote:
> > Thanks for the input Nigel!
> > Well, I'm not an expert in electronics therefore I do not know much about suitable photodetector but we need this instrument not to monitor bacterial growth for several hours. We need to measure with good accuracy the cell density on the spot and to distinguish clearly between a 0.6 and 0.8 Abs at 600 nm (or 650 nm if 600 is not possible). If I'm correct this requires some accuracy. In my experience also the most simple of the instruments that I used at work were based on this schematics:
> > <image.jpeg>
> > On 24 October 2012 22:52, Nigel Worsley <nig...@googlemail.com> wrote:
> > link to a nice diagram of the absorbance at 650 nm for bacteria
> > you wouldn't need a spectrometer for that, just a cheap 650nm LED and a suitably
> > linear photodetector. And a processor to do the calibration and tedious monitoring
> > of the absorption for several hours so that the result is ready when you get back
> > from the pub :)
