Injection of Ultrasmall Samples and Single Molecules into Tapered Capillaries

Chiu, Daniel T.; Hsiao, A. I.; Gaggar, Anuj; Garza-López, Roberto A.; Orwar, Owe; Zare, Richard N.

doi:10.1021/ac961226g

Cited by 53 publications

(38 citation statements)

References 47 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…To fuse a cell or vesicle to another cell, individual manipulation of at least one of the fusion partners is required for alignment. It is well documented that individual cells, as well as other biological structures, including organelles of small dimension, can be manipulated and moved at will in solution by using optical trapping with highly focused laser beams (10)(11)(12)(13). Here, a cell in solution was trapped by an IR laser beam and brought into contact with an adherent cell, by using the setup schematically shown in Fig.…”

Section: Resultsmentioning

confidence: 99%

Manipulating the genetic identity and biochemical surface properties of individual cells with electric-field-induced fusion

Strömberg

Ryttsén

Chiu

et al. 2000

Proc. Natl. Acad. Sci. U.S.A.

Self Cite

View full text Add to dashboard Cite

Section: Resultsmentioning

confidence: 99%

Manipulating the genetic identity and biochemical surface properties of individual cells with electric-field-induced fusion

Strömberg

Ryttsén

Chiu

et al. 2000

Proc. Natl. Acad. Sci. U.S.A.

Self Cite

View full text Add to dashboard Cite

“…At the boundary of the droplet, one can write a mass-conservation equation relating the change of the volume of the droplet to the mass flux leaving the droplet: (1) where V is the droplet volume, ρ is the density of the droplet (pure water), a is the radius of the droplet, D is the mass diffusion coefficient of water in the external organic phase, C is the external concentration (solubility) of water, and Mw is the molecular weight of water.…”

Section: Laser-onmentioning

confidence: 99%

Controlled Shrinkage and Re-expansion of a Single Aqueous Droplet inside an Optical Vortex Trap

2007

Self Cite

View full text Add to dashboard Cite

This paper describes the shrinkage and re-expansion of individual femtoliter-volume aqueous droplets that were suspended in an organic medium and held in an optical vortex trap. To elucidate the mechanism behind this phenomenon, we constructed a heat and mass transfer model and carried out experimental verifications of our model. From these studies, we conclude that an evaporation mechanism sufficiently describes the shrinkage of aqueous droplets held in a vortex trap, while a mechanism based on the supersaturation of the organic phase by water that surrounds the droplet adequately explains the re-expansion of the shrunk droplet. The proposed mechanisms correlate well with experimental observations using different organic media, when H 2 O was replaced with D 2 O, and when an optical tweezer was used to induce droplet shrinkage rather than an optical vortex trap. For H 2 O droplets, the temperature rise within the droplet during shrinkage was on the order of 1K or less, owing to the rapid thermal conduction of heat away from the droplet at the microscale and the sharp increase in solubility for water by the organic phase with slight elevations in temperature. Because most chemical species confined to droplets can be made impenetrable to the aqueous/organic interface, a change in the volume of aqueous droplets translates into a change in concentration of the dissolved species within the droplets. Therefore, this phenomenon should find use in the study of fundamental chemical processes that are sensitive to concentration, such as macromolecular crowding and protein nucleation and crystallization.

show abstract

“…The optical trap was built in-house ( Figure 2A) and has been described previously. 25 The output of a single-mode MOPA laser diode (model SDL-5762-A6, SDL, Inc., San Jose, CA) was sent through a spatial filter (model 900, Newport Corp., Irvine, CA) and then reflected from a near-IR mirror. The beam was then passed through a dichroic mirror and reflected from a polychroic mirror (Chroma Technology Corp., Brattleboro, VT) that was placed in the filter cube mount of an inverted microscope (Nikon Diaphot, Technical Instrument Co., San Francisco, CA).…”

Section: Injection Of Single Vesicles and On-column Derivatizationmentioning

confidence: 99%

Separation and Characterization of Amines from Individual Atrial Gland Vesicles ofAplysiacalifornica

Lillard¹,

Chiu²,

Scheller³

et al. 1998

Anal. Chem.

Self Cite

View full text Add to dashboard Cite

Several amine-containing components of individual vesicles from the atrial gland of Aplysia californica were identified with capillary electrophoresis (CE). On-line derivatization with naphthalene-2,3-dicarboxaldehyde was performed, and the derivatized amine-containing components were detected with laser-induced fluorescence (LIF). Amino acids, including taurine, that had not been determined previously in atrial gland vesicles were observed by using CE-LIF, and their identities were confirmed with CE, HPLC, NMR, and electrospray ionization mass spectrometry. The finding that taurine is packaged and stored into secretory vesicles supports the hypothesis that taurine may exhibit neuromodulatory activity. The bioactive peptides, well-known to be in atrial gland vesicles, were detected in lysed vesicle samples fractionated with HPLC and analyzed by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. These peptides were also observed in single-vesicle runs with CE-LIF. The atrial gland vesicles (ranging from 0.5 to 2 μm diameter and 65 aL to 4 fL volume, respectively) studied in this work represent the smallest biological entities to be analyzed chemically on an individual basis.The goal of analyzing individual biological cells has been realized with various microanalytical techniques. The motivation behind studying this specialized sample type is the heterogeneity that is present in the cell populations that comprise tissues. The measurement of an average value for a specific parameter of a population does not necessarily reflect the range of values resulting from individual members of the population. Although ensemble measurements can reveal abnormalities in a cell population, these measurements do not indicate intercellular differences that may provide more important clues about the history or future of a cell.Reports of single-cell analyses date back to the 1950s, in which single neurons were studied. 1-4 Since that time, several methods, including separations, have been used to analyze single cells. 5-23 Owing to its high sensitivity, laser-induced fluorescence (LIF) has played a significant role in the chemical analysis of individual cells with capillary electrophoresis (CE), 5,6 including wavelength-resolved LIF of neurotransmitters in single neurons. 7 Novel analyses of single cells with CE include cytoplasmic sampling from 8 and transporting solutes into 9 † Department of Chemistry, Stanford University. EXPERIMENTAL SECTIONReagents.All chemicals were from Mallinckrodt (Paris, KY) unless otherwise specified. KCN and KCl were from J. T. Baker, Inc. (Phillipsburg, NJ), and acetonitrile was obtained from Fisher (Fairlawn, NJ). Amino acids were from Sigma Chemical (St. Louis, MO). All solutions for CE-LIF, including buffers, naphthalene-2,3-dicarboxaldehyde (NDA) dilutions, vesicle extracts, and off-column derivatization reactions, were prepared and stored in glass vials. These glass vials were also used to contain the running buffer for CE-LIF. Sodium tetraborate solutions were...

show abstract

Injection of Ultrasmall Samples and Single Molecules into Tapered Capillaries

Cited by 53 publications

References 47 publications

Manipulating the genetic identity and biochemical surface properties of individual cells with electric-field-induced fusion

Manipulating the genetic identity and biochemical surface properties of individual cells with electric-field-induced fusion

Controlled Shrinkage and Re-expansion of a Single Aqueous Droplet inside an Optical Vortex Trap

Separation and Characterization of Amines from Individual Atrial Gland Vesicles ofAplysiacalifornica

Contact Info

Product

Resources

About