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Questions related from Rohan Aggarwal
Electrochemical sensors have an inherent advantage for being simple, cheap (glucometers), especially for nucleic acid assays. Yet there are very few health devices in the market for point of care...
12 December 2019 8,643 3 View
We use purified hTSH (in PBS), but have issue with stability of the sample. Since the purified hormone is highly unstable the activity reduces drastically at room temperature. We had added BSA to...
07 July 2019 8,699 4 View
We do not have a system for oxygen plasma, corona discharge or ozone in our lab. We wanted to create reactive surface for our immunoassay on PDMS, such that it can bind to APTES. We have been...
04 April 2019 3,472 3 View
I know it could be a little naive question. Wanted to gather views and experiences on likelihood of stock solutions of antibodies, in PBS (with sodium azide) likely to suffer degradation due to...
03 March 2019 5,176 7 View
We are performing a microfluidics based immunoassay reaction, with a modified system. We have been getting lower readings for our spiked samples, compared to control samples. For example, if...
01 January 2019 6,430 3 View
We have reconstituted human TSH hormone (Sigma), that we use in our immunoassay system. How long can we keep the same at 4 deg before any sort of loss in activity is observed? We do multiple test...
10 October 2018 4,569 0 View
We are trying to desiccate BSA coated polystyrene microparticles (2-3 um diameter) in a plastic microchannel blocked with BSA/Casein + Tween 20. When we are trying to reconstitute the particles,...
08 August 2018 8,709 0 View
We recently got TSH hormone from Sigma. On the first day, we ran our assay, and the results were fine. On the second day, the activity has somehow reduced by 90%. How is this possible? We...
08 August 2018 435 2 View
We are optimizing the assay parameters for our TSH immunoassay. We had been using a 7.4 pH PBS buffer for antibody coating so far, but now want to evaluate if changing the pH of the coating buffer...
07 July 2018 3,725 2 View
We wish to desiccate protein coated polystyrene microparticles with some other proteins inside a microchannel. We tried doing so using normal air drying (non-sterile air, from a blower). But when...
06 June 2018 3,927 1 View
We are making microchannels by machining in Plexiglas (PMMA). We want to cover the same with Pressure sensitive adhesive tape (PSA tape) to close the channels to improve turnaround time of our...
04 April 2018 9,710 1 View
The first method is silanization of PDMS surface with 50% v/v in ethanol followed by treatment with Glutaraldehyde which presents a site for antibody binding. In the second method BSA is passively...
04 April 2018 6,015 5 View
We are looking to buy a pressure based flow control system and have quotations from Fluigent and Elveflow. Fluigent system comprises of FLOW EZ with M-switch, manifold and flow sensor with...
12 December 2017 9,126 2 View
We wish to perform some steady state simulations for our microfluidics related work. We are planning to buy a desktop system to do so rather than do it on cloud, due to some internal issues. But I...
11 November 2017 6,759 4 View
We are looking for a micro-fabrication method/equipment (Company name and product name will be very helpful) for rapid prototyping of micro-channels. Preferred materials are plastics such as...
06 June 2017 1,965 1 View
I performed an immunoassay in a microchannel (0.4 mm x 6 mm x 60 mm), with 50 ul and 25 ul sample volumes. I am getting the same reading for both the volumes across numerous tries. Is this...
05 May 2017 6,456 3 View
Channel is wide with width 6 mm, height 0.4 mm, length 60 mm. I want to achieve flow rates from 1 ul/min to 25 ul/min in my system. Flow rates below say 100 ul/min (using syringe pump with 2 ml...
03 March 2017 5,767 5 View
We want to place a large order, but we are not sure how reliable they are. Our local suppliers costs us a lot more, since they also source it from similar foreign merchants, and we wanted to cut...
01 January 2017 2,741 2 View
There are a number of microfluidic assays which use microbeads in unbound state (not fixed to solid wall), followed by fluorescent based signal measurement. But there are no parameters mentioned...
01 January 2017 2,041 8 View
I believe they should only have an effect on the diffusion distance and in controlling flow velocity or keeping Reynolds no in the Stokes flow regime. Is there any other significance to this...
01 January 2017 8,059 3 View
I am developing an immunoassay and am at a proof of concept phase. Since we are regularly experimenting with different ideas to find the best solution, using antibodies is being expensive. We...
11 November 2016 1,204 6 View
I performed passive adsorption of protein on my PS microspheres, but there is some minor visible clumping in the final solution. I had performed all steps as per a previously used protocol that...
11 November 2016 3,510 2 View
I have a polystyrene microsphere sourced which are not functionalized, and hence do not have any surface group such as a carboxyl or amine. I wish to introduce a surface group such as a carboxyl...
09 September 2016 9,013 14 View
I coated anti-PSA antibody on PS microspheres (2.5 um) as per the method given here- https://www.bangslabs.com/sites/default/files/imce/docs/TechNote%20204%20Web.pdf I used Citrate-phosphate...
08 August 2016 6,712 3 View
There are number of methods for surface modification/functionalization with PEI, using N-hydroxysuccinimide (NHS), NHS derivatives, EDC, EDC derivatives etc. but no comparative analysis or...
08 August 2016 8,094 2 View
