NMR analysis on microfluidic devices by remote detection
We present a novel approach to perform high-sensitivity NMR imaging and spectroscopic analysis on microfluidic devices. The application of NMR, the most information rich spectroscopic technique, to microfluidic devices remains a challenge because the inherently low sensitivity of NMR is aggravated by small fluid volumes leading to low NMR signal, and geometric constraints resulting in poor efficiency for inductive detection. We address the latter by physically separating signal detection from encoding of information with remote detection. Thereby, we use a commercial imaging probe with sufficiently large diameter to encompass the entire device, enabling encoding of NMR information at any location on the chip. Because large-diameter coils are too insensitive for detection, we store the encoded information as longitudinal magnetization and flow it into the outlet capillary. There, we detect the signal with optimal sensitivity using a solenoidal microcoil, and reconstruct the information encoded in the fluid. We present a generally applicable design for a detection-only microcoil probe that can be inserted into the bore of a commercial imaging probe. Using hyperpolarized 129Xe gas, we show that this probe enables sensitive reconstruction of NMR spectroscopic information encoded by the large imaging probe while keeping the flexibility of a large coil.
- Research Organization:
- Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)
- Sponsoring Organization:
- USDOE Director. Office of Science. Office of Basic EnergySciences. Materials Sciences and Engineering Division; SchweizerischerNationalfonds Fellowship
- DOE Contract Number:
- DE-AC02-05CH11231
- OSTI ID:
- 881836
- Report Number(s):
- LBNL-58631; R&D Project: 508601; BnR: KC0203010; TRN: US200612%%924
- Journal Information:
- Analytical Chemistry, Vol. 77, Issue 24; Related Information: Journal Publication Date: 12/15/2005
- Country of Publication:
- United States
- Language:
- English
Similar Records
An optimized microfabricated platform for the optical generation and detection of hyperpolarized 129Xe
Portable, Low-cost NMR with Laser-Lathe Lithography Produced