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Title: Electro-hydrodynamic extraction of DNA from mixtures of DNA and bovine serum albumin
We report separation of genomic DNA (48 kbp) from bovine serum albumin (BSA) by the electro-hydrodynamic coupling between a pressure-driven flow and a parallel electric field. Electro-hydrodynamic extraction exploits this coupling to trap DNA molecules at the entrance of a microfluidic contraction channel, while allowing proteins and salts to be flushed from the device. Samples (10 μL) containing λ-DNA (1 ng) and BSA (0.3 mg) were injected directly into the device and convected to the contraction channel entrance by a flowing buffer solution. The DNA remains trapped in this region essentially indefinitely, while proteins and salts are eluted. The effectiveness of the concept has been assessed by fluorescence measurements of DNA and BSA concentrations. Electro-hydrodynamic extraction in a single-stage device was found to enhance the concentration of DNA 40-fold, while reducing the BSA concentration by four orders of magnitude. The relative concentrations of DNA to BSA at the contraction channel entrance can be as large as 1.5 : 1, corresponding to an A260/280 ratio of 1.9. The maximum yield of DNA from a salt-free solution is 50%, while salted (150 mM) solutions have a lower yield (38%).  more » « less
Award ID(s):
1804302
NSF-PAR ID:
10233003
Author(s) / Creator(s):
; ; ;
Date Published:
Journal Name:
The Analyst
Volume:
145
Issue:
16
ISSN:
0003-2654
Page Range / eLocation ID:
5532 to 5538
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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     Accumulation of inorganic phosphate (Pi) may contribute to muscle fatigue by precipitating calcium salts inside the sarcoplasmic reticulum (SR). Neither direct demonstration of this process nor definition of the entry pathway of Piinto SR are fully established.

     We showed that Pipromoted Ca2+release at concentrations below 10 mmand decreased it at higher concentrations. This decrease correlated well with that of [Ca2+]SR.

     Pre‐treatment of permeabilized myofibres with 2 mmClchannel blocker 9‐anthracenecarboxylic acid (9AC) inhibited both effects of Pi.

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