Abstract:
:High-resolution measurement of membrane capacitance in the whole-cell-recording configuration can be used to detect small changes in membrane surface area that accompany exocytosis and endocytosis. We have investigated the noise of membrane capacitance measurements to determine the fundamental limits of resolution in actual cells in the whole-cell mode. Two previously overlooked sources of noise are particularly evident at low frequencies. The first noise source is accompanied by a correlation between capacitance estimates, whereas the second noise source is due to "1/f-like" current noise. An analytic expression that summarizes the noise from thermal and 1/f sources is derived, which agrees with experimental measurements from actual cells over a large frequency range. Our results demonstrate that the optimal frequencies for capacitance measurements are higher than previously believed. Finally, we demonstrate that the capacitance noise at high frequencies can be reduced by compensating for the voltage drop of the sine wave across the series resistance.
journal_name
Biophys Jjournal_title
Biophysical journalauthors
Chen P,Gillis KDdoi
10.1016/S0006-3495(00)76464-2subject
Has Abstractpub_date
2000-10-01 00:00:00pages
2162-70issue
4eissn
0006-3495issn
1542-0086pii
S0006-3495(00)76464-2journal_volume
79pub_type
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journal_title:Biophysical journal
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pub_type: 杂志文章,评审
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更新日期:2013-10-01 00:00:00
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pub_type: 杂志文章
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更新日期:2016-05-24 00:00:00
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pub_type: 杂志文章
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pub_type: 杂志文章
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pub_type: 杂志文章
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更新日期:1980-06-01 00:00:00
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