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Capillary electrophoresis coupled to mass spectrometry (CE-MS) is increasingly gaining momentum as an analytical tool in metabolomics, thanks to its ability to ob- tain information about the most polar elements in biological samples. This has been helped by improvements in peak robustness by means of mobility-scale representations of the electropherograms (mobilograms). As a necessary step towards the use of CE- MS for untargeted metabolomics data, the authors previously developed and introduced the ROMANCE software, with the purpose of automating mobilogram generation for large untargeted datasets while offering a simple and self-contained user interface. In natural continuation ROMANCE has been upgraded to its v2 to read other types of data (targeted MS data and 2D UV-like electropherograms), offer more flexibility in the transformation parameters (including field ramping delays and the use of sec- ondary markers), more measurement conditions (depending on detection and ionization modes), and most importantly tackle the issue of quantitative CE-MS. To prepare the ground for such an upgrade, we present a review of the current theoretical framework with regards to peak reproducibility and quantification, and we develop new formulas for multiple marker peak area corrections, for anticipating peak position precision, and for assessing peak shape distortion. We then present the new version of the software, and validate it experimentally. We contrast the multiple marker mobility transfor- mations with previous results, finding increased precision, and finally we showcase an application to actual untargeted metabolomics data.

We report the first successful implementation of a multiplexing method on a standard capillary electrophoresis system with UV detection that is independent of additional hardware. This was achieved using the Hadamard transform approach and employing vial exchange and voltage suspensions for translation of pseudorandom binary sequence elements into sample and background electrolyte injections of a capillary zone electrophoresis separation. Sequences exceeding peak capacity of the capillary were subdivided into shorter subsequences measured successively and realigned afterward based on EOF marker or analyte peaks. This way, we realized and deconvoluted modulation sequences as long as 8-bit (255 injections) for two systems containing either AMP or a mixture of the nucleotides (A,C,G,U)MP resulting in electropherograms of considerably improved signal-to-noise ratio. We achieved factors of intensity enhancement of around 6.9 and 5.2, respectively (theoretical maximum 8.0). This contribution, further, presents experimental and simulation studies on the effects on zones during injection and separation when experiencing voltage suspensions. Besides analysis of EOF behavior and influence of diffusion dispersion, we also provide data on the significance of specific electrophoretic errors such as peak position shift, inconsistent sample injection, and peak broadening on the quality of the inverse Hadamard transform. Moreover, the application of our approach to the practical analysis of a milk sample is described. The results demonstrate the applicability of multiplexing on unmodified standard CE instrumentation and establish a new suitable methodology to enhance the low sensitivity of on-column UV detection in capillary electrophoresis.

In the present work, we demonstrate a novel approach to improve the sensitivity of the "out of lab" portable capillary electrophoretic measurements. Nowadays, many signal enhancement methods are (i) underused (nonoptimal), (ii) overused (distorts the data), or (iii) inapplicable in field-portable instrumentation because of a lack of computational power. The described innovative migration velocity-adaptive moving average method uses an optimal averaging window size and can be easily implemented with a microcontroller. The contactless conductivity detection was used as a model for the development of a signal processing method and the demonstration of its impact on the sensitivity. The frequency characteristics of the recorded electropherograms and peaks were clarified. Higher electrophoretic mobility analytes exhibit higher-frequency peaks, whereas lower electrophoretic mobility analytes exhibit lower-frequency peaks. On the basis of the obtained data, a migration velocity-adaptive moving average algorithm was created, adapted, and programmed into capillary electrophoresis data-processing software. Employing the developed algorithm, each data point is processed depending on a certain migration time of the analyte. Because of the implemented migration velocity-adaptive moving average method, the signal-to-noise ratio improved up to 11 times for sampling frequency of 4.6 Hz and up to 22 times for sampling frequency of 25 Hz. This paper could potentially be used as a methodological guideline for the development of new smoothing algorithms that require adaptive conditions in capillary electrophoresis and other separation methods.

Quantitative analysis in capillary electrophoresis based on time-scale electropherograms generally uses time-corrected peak areas to account for the differences in apparent velocities between solutes. However, it could be convenient and much more relevant to change the time-scale electropherograms into mass relative distribution of the effective mobility or any other characteristic parameter (molar mass, chemical composition, charge density, ...). In this study, the theoretical background required to perform the variable change on the electropherogram was developed with an emphasis on the fact that both x and y axes should be changed when the time scale electropherograms are modified to get the distributions. Applications to the characterization of polymers and copolymers by different modes of capillary electrophoresis (CE) are presented, including the molar mass distribution of poly-L-lysine oligomers by capillary gel electrophoresis (CGE), molar mass distribution of end-charged poly-l-alanine by free solution CE, molar mass distribution of evenly charged polyelectrolytes by CGE, and charge density distribution of variously charged polyelectrolytes by free solution CE.

Nonequilibrium capillary electrophoresis of equilibrium mixtures (NECEEM) facilitates determination of both the kinetic constants (k(off)) and the equilibrium constants (K(d)) of complex dissociation from a single experiment. A typical NECEEM electropherogram consists of two peaks and an "exponential bridge" between them, smoothly merging into the peaks. The values of k(off) and K(d) are usually calculated with simple algebraic formulas, by utilizing the areas of the peaks and the bridge. Accurate determination of the two constants requires accurate positioning of the two boundaries separating the bridge from the peaks. Here, we propose a more systematic method for the determination of boundaries between the peaks and the bridge. The method involves a simple geometrical analysis of a NECEEM electropherogram based on an assumption of symmetry in ordinary electrophoretic peaks. To test the method, we (i) constructed a series of computer-simulated NECEEM electropherograms, (ii) determined the two boundaries with our method, and (iii) calculated the values of k(off) and K(d). We found that the deviation of the calculated values from those used to simulate the electropherograms did not exceed 15% for k(off) and 25% for K(d), as long as the peaks and the bridge were visually identifiable. We finally applied the method to the determination of K(d) and k(off) values for the interaction between AlkB protein and its DNA aptamer. The developed method for rational boundary determination in NECEEM will facilitate accurate data analysis in a simple and efficient manner.

Diagonal capillary electrophoresis is a form of two-dimensional capillary electrophoresis that employs identical separation modes in each dimension. The distal end of the first capillary incorporates an enzyme-based microreactor. Analytes that are not modified by the reactor will have identical migration times in the two capillaries and will generate spots that fall on the diagonal in a reconstructed two-dimensional electropherogram. Analytes that undergo enzymatic modification in the reactor will have a different migration time in the second capillary and will generate spots that fall off the diagonal in the electropherogram. We demonstrate the system with immobilized alkaline phosphatase to monitor the phosphorylation status of a mixture of peptides. This enzyme-based diagonal capillary electrophoresis assay appears to be generalizable; any post-translational modification can be detected as long as an immobilized enzyme is available that reacts with the modification under electrophoretic conditions.

This paper describes a novel application of carbon nanotubes for improving the resolution of a native PAGE in the detection of human serum proteins. Carbon nanotubes were functionalized and introduced into the gel of native PAGE system, and the electropherogram showed sharp, clear bands. Furthermore, the separation of some most important proteins was improved, and the established method could be applied for the detection of sera from patients with liver diseases.

The continuous nature of micro free-flow electrophoresis (mu-FFE) was used to monitor the effect of a gradient of buffer conditions on the separation. This unique application has great potential for fast optimization of separation conditions and estimation of equilibrium constants. COMSOL was used to model pressure profiles in the development of a new mu-FFE design that allowed even application of a buffer gradient across the separation channel. The new design was fabricated in an all glass device using our previously published multiple-depth etch method (Fonslow, B. R.; Barocas, V. H.; Bowser, M. T. Anal. Chem. 2006, 78, 5369-5374, ref 1). Fluorescein solutions were used to characterize the applied gradients in the separation channel. Linear gradients were observed when buffer conditions were varied over a period of 5-10 min. The effect of a gradient of 0-50 mM hydroxypropyl-beta-cyclodextrin (HP-beta-CD) on the separation of a group of 4-fluoro-7-nitro-2,1,3-benzoxadiazole (NBD-F) labeled primary amines was monitored as a proof of concept experiment. Direct comparisons to capillary electrophoresis (CE) separations performed under the same conditions were made. Gradient mu-FFE recorded 60 separations during a 5 min gradient allowing nearly complete coverage across a range of HP-beta-CD concentrations. In comparison, 4 h were required to assess 15 sets of conditions across the same range of HP-beta-CD concentrations using CE. Qualitatively, mu-FFE separations were predictive of the migration order and spacing of peaks in CE electropherograms measured under the same conditions. Data were fit to equations describing 1:1 analyte-additive binding to allow a more quantitative comparison between gradient mu-FFE and CE.

This report describes a method of controlling the sensitivity and reproducibility of a microchip-based immunoassay by using isotachophoresis to preconcentrate the antigen and antibody prior to binding. Gel electrophoresis separation is coupled to the preconcentration step to separate the immunocomplex products formed. The system employs a quartz-based LabChip that automates the metering, preconcentration, reaction, separation, and detection. The system also uses a handoff mechanism that switches the immunocomplex from the stacking mode to the separation mode. We show that the handoff timing affects the data quality and repeatability of the electropherograms, and we demonstrate an automatic handoff mechanism to precisely control the signal intensity and separation of peaks of interest. In so doing, the automatic handoff mechanism also improves the reproducibility of the assay. When applied to the homogeneous liquid-phase detection of alpha-fetoprotein, a common tumor marker, the system shows a greater than 200-fold stacking of specific analytes of interest.

Identification of factors that determine meat tenderness is of high priority. The aim of this work was to develop a method that can detect indicators of proteolysis in meat early postmortem. The method was validated on pork samples. A procedure to detect differences of extractable lower molecular weight compounds after a prerigor freeze/thaw cycle of meat was developed using capillary electrophoresis. The procedure was able to separate 39 peaks in the electropherograms. Eight of the peaks were correlated (P < 0.1) to Warner-Bratzler shear forces 1 day postmortem (WB1). A multiple linear regression model explained 69% of the variation in WB1 using the areas of four peaks. Several of the peaks used in modeling WB1 were related to the at-slaughter activity of the calpain system. The results presented show that the developed method is able to detect indicators of proteolysis and tenderness at an early time point after slaughter. The method is a new tool intended for studies regarding the mechanisms of postmortem proteolysis and tenderization.

A novel, rugged capillary electrophoresis-electrospray ionization (CE-ESI) interface where the separation column, an electrical porous junction, and the spray tip are integrated on a single piece of a fused-silica capillary is described. ESI is accomplished by applying an electrical potential through an easily prepared porous junction across a 3−4-mm length of fused silica. A stable electrospray is produced at nanoflow rates generated in the capillary by electrophoretic and electroosmotic forces. The interface is particularly well suited for the detection of low-femtomole levels of proteins and peptides. The ruggedness of this interface was evident by the continuous operation of the same column for over a 2-week period with no detectable deterioration in separation or electrospray performance. The new interface was used for the LC−ESI-MS separation and analysis of peptides and proteins. Injection of 25 fmol of [Glu1]-fibrinopeptide B using the new device produced a CE−ESI-MS electropherogram with a signal...

The application of a Hadamard transform technique to microchip electrophoresis is described. The sample is electrokinetically injected into a separation channel and is then detected by diode laser-induced fluorometry. The sample and buffer solutions are introduced into the channel by controlling the high voltages applied to the solutions, according to a code determined by a Hadamard matrix. The S/N ratio of the signal in the electropherogram can be improved by a factor of 5 in comparison with that obtained by a conventional single-injection method, although an 8-fold improvement is theoretically predicted when a 255-order matrix is used.

We propose a new method that allows the use of low-affinity aptamers as affinity probes in quantitative analyses of proteins. The method is based on nonequilibrium capillary electrophoresis of the equilibrium mixture (NECEEM) of a protein with its fluorescently labeled aptamer. In general, NECEEM of a protein with a fluorescently labeled aptamer generates an electropherogram with three characteristic features: two peaks and an exponential curve. Two peaks correspond to (i) the equilibrium amount of free aptamer in the equilibrium mixture and (ii) the amount of the protein-aptamer complex that remains intact at the time of detection. The exponential part is ascribed to the complex decaying during separation under nonequilibrium conditions. Simple analysis of the three features in experiments with known concentrations of the protein can be used for the determination of the equilibrium dissociation constant, Kd, of the aptamer-protein complex. Similar analysis of the three features in the experiment with unknown concentration of the protein and known Kd value allows the determination of the protein concentration. In this proof-of-principle work, the NECEEM method was applied to the analysis of thrombin using a fluorescein-labeled aptamer under the conditions at which the protein-aptamer complex completely decayed during the separation. We demonstrated that, despite the decay, as few as 4 x 10(6) molecules of the protein could be detected with NECEEM without sacrificing the accuracy. This sensitivity is comparable with that reported by others for the aptamer-based equilibrium method. Thus, the proposed NECEEM-based method allows the use of aptamers for highly sensitive affinity analysis of proteins even when protein-aptamer complexes are unstable.

Cross-correlation electrophoresis with fluorescence detection on a microchip device was used to resolve a mixture of 63 pM fluorescein and 70 pM dichlorofluorescein. The signal-to-noise ratios of analyte peaks in a correlogram derived from a 9-bit pseudorandom injection sequence were ∼17 for dichlorofluorescein and ∼6 for fluorescein. In contrast, neither peak was detected in a conventional electropherogram obtained on the microchip. Detection limits estimated from a correlogram derived from the average of 12 7-bit correlograms were 6.5 pM dichlorofluorescein and 21 pM fluorescein. These are the lowest detection limits reported for a microchip separation device using analog detection and the first example of cross-correlation electrophoresis on a monolithic device. The small injection volumes, injection reproducibility, and rapid separations enabled by microchip devices make cross-correlation multiplex injection schemes a viable approach for achieving enhanced sensitivity.

A new convolution-detection method was developed which converts multiple-point (Shah function) detection, time-domain electropherograms into frequency-domain plots by means of a Fourier transformation, allowing the analytes' speeds to be viewed in terms of their "blinking" frequency; we have named this method Shah convolution Fourier transform detection, or SCOFT. This paper represents proof of principle of the detection concept. A micromachined glass stucture with a patterned layer of Cr on its top surface to form regularly spaced detection slits was used to perform capillary electrophoresis separations with 55-point, laser-induced fluorescence detection over 3.78 cm of the 6.6 cm separation channel. While this method can be easily integrated into a miniaturized total analysis system (μ-TAS), the principle is equally applicable to detection in full-sized analytical instrumentation. Single-component samples (fluorescein) migrating through the separation channel yielded a single peak in the frequency domain, and two-component samples (fluorescein and fluorescein isothiocyanate) yielded two resolved peaks, each at the expected frequency; harmonics were also observed. Advantages were seen in terms of isolation of the analyte peaks from interference such as baseline drift and line noise. Resolution is somewhat inferior to that seen in single-point detection, but it is thought that improved chip design and mathematical and instrument optimization will lead to performance superior to that of single-point detection.

An automated and integrated system for DNA typing directly from blood samples has been developed. The multiplexed eight-array system is based on capillary microfluidics and capillary array electrophoresis. Three short-tandem-repeat loci, vWA, THO1, and TPOX, are coamplified simultaneously in a fused-silica capillary by a hot-air thermocycler. Blood is directly used as the sample for polymerase chain reaction (PCR) without any pretreatment. Modifications of standard protocols are necessary for direct PCR from blood. A programmable syringe pump plus a set of multiplexed liquid nitrogen freeze/thaw switching valves are employed for liquid handling in the fluid distribution network. The system fully integrates sample loading, PCR, addition of an absolute standard, on-line injection of sample and standards, separation and detection. The genotypes from blood samples can be clearly identified in eight parallel channels when the electropherograms are compared with that of the standard allelic ladder by itself. Regeneration and cleaning of the entire system prior to subsequent runs are also integrated into the instrument. The instrumentation is compatible with future expansion to hundreds of capillaries to achieve even higher throughput.

Continued progress in cellular physiology requires new measurement strategies which can be applied to solitary cells. Since many cellular signaling pathways act on time scales of a few seconds, there is a critical need for single-cell techniques with subsecond time resolution. Capillary electrophoresis shows great promise as a tool for the analysis of individual cells. In the present work, we describe a technique to load a capillary with picoliter to nanoliter volumes of cytoplasm and initiate electrophoresis in less than 500 ms. When cytoplasm was sampled from a Xenopus laevis oocyte previously loaded with fluorescein, calcium green, or a mixture of the two fluorophores, their fluorescent peaks were readily identifiable on the electropherogram. Since the volume of cytoplasm (or = 30 nL) loaded into the capillary was much smaller than the 1 microL oocyte volume, spatially localized biochemical measurements were also possible. To demonstrate the utility of this new technique, the activity of the enzyme beta-galactosidase was measured in small regions of the Xenopus oocyte. Subcellular, subsecond sampling of oocyte cytoplasm will enable biochemical measurements with the resolution required to understand many cellular signal transduction pathways.

Two new variants on capillary zone electrophoresis (CZE) are described and experimentally investigated. In vacancy CZE the sample, diluted with a background electrolyte, fills the electrode vessels and the separation capillary. When pure background electrolyte is injected, the resulting electropherogram represents the composition of the sample. The electropherogram is almost identical with the result of a conventional CZE experiment. In differential CZE the sample again fills the electrode vessels and the separation compartment. After injection of a slightly different sample, a differential electropherogram is obtained that represents the differences between the two samples. The retention times of both new variants are comparable with conventional CZE, the separation efficiency, in terms of theoretical plates, is marginally lower, and both show good quantitative characteristics. The concept of vacancy electrophoresis explains the origin of unexpected system peaks in conventional CZE when multiple co-ions in the background electrolyte are used.

The combination of capillary electrophoresis (CE) with electrospray ionization (ESI) time-of-flight mass spectrometry (TOF-MS) has recently been demonstrated. When CE is combined with TOF-MS using an electrospray interface, the method provides fast, high-resolution separations with rapid mass analysis and the potential for very high sensitivity. In analyzing the data, one first reconstructs an electropherogram from the data set and then identifies peaks in the mass spectra. The mass spectra corresponding to the peaks in the electropherogram are then inspected to enable solute identification. However, background noise often prevents detection of peaks in the reconstructed electropherogram, thus interfering with the analysis. In this work we demonstrate alternative electropherogram reconstruction techniques that enhance its signal-to-noise ratio, allowing more immediate identification of the number of components in a mixture and their corresponding retention times. The techniques described here should also be adaptable for on-line analysis of CE-ESI-TOF data and the combination with other separation techniques coupled to mass spectrometry (e.g., LC/MS), as well as any multichannel detection scheme. 21 refs., 4 figs., 1 tab.

A near-infrared time-correlated single-photon counting instrument was developed for on-line fluorescence lifetime determinations of components separated by capillary electrophoresis (CE). The lifetimes of the migrating components were determined using maximum likelihood estimators, which are computationally easy to perform and yield values with high precision and favorable accuracies in the limit of low photocounts within the decay profile. The laser source used in the present system was a passively mode-locked Ti-sapphire laser with a single-photon avalanche diode serving as the fast detector. The instrument response function of this system was determined to be 165 ps (fwhm). Electrophorectic separation of two near-IR dyes, DTTCI (cationic) and IR-125 (anionic), in a 95:5 methanol/water running buffer (pH = 9.5) produced electrophoretic peak widths at the base of approximately 1 -9 s, which set the integration time for collection of the decay profiles. At a loading level of 1.42 zmol for IR-125 and 49 zmol for DTTCI, lifetime values were determined to be 482 +/- 14 ps for IR-125 and 943 +/- 23 ps for DTTCI, which agreed favorably with the lifetimes determined for these dyes using static measurements at high concentrations. To minimize background resulting from scattered photons in ultradilute conditions, which introduces bias into the lifetime determination, the calculation was initiated at a fixed time delay with respect to the excitation pulse. To demonstrate the feasibility of making lifetime determinations in capillary gel electrophoresis, where the gel can produce high scattering backgrounds, the lifetimes of C-terminated fragments produced from the M13mp 18 template and labeled at the 5' end of a universal M13 sequencing primer with a near-IR fluorescent tag were determined. The collection of lifetimes for 30 different peaks in the electropherogram yielded a mean value of 581 ps and a standard deviation of +/- 9 ps.

An automated fraction collection interface is used in conjunction with matrix-assisted laser desorption/ionization (MALDI) time-of-flight mass spectrometry to analyze material isolated by capillary electrophoresis (CE). CE fractions are deposited directly on the MALDI probes so that individual peaks from the electropherogram are associated with a single sample spot on the probe. MALDI matrices with high acid concentrations afford enhanced tolerance of electrophoresis buffers. The utility of this hybrid instrument is demonstrated by separation and mass analysis of a tryptic digest of cytochrome c and synthetic mixtures of four proteins. Mass assignments corresponding to the protonated molecular ions are in good agreement with those predicted from molecular structure. Miniaturization of the interface affords enhanced sensitivity, with good-quality spectra from separations of as little as 25 fmol of protein.

Various excitation schemes for distributing a laser beam to a large number of capillaries in an array are evaluated. This led to the construction of a multiplexed system for monitoring the electrophoresis of DNA fragments in 100 capillaries. The laser-excited fluorescence signals from each capillary are simultaneously recorded at the rate of 0.6 frame/s by a CCD camera. The reconstructed electropherograms show excellent reproducibility and minimal cross-talk. The system provides for two simultaneous excitation wavelengths so that it can be adapted for two-color, two-intensity DNA sequencing based on the commercial four-dye chemistry. Only 20 mW per laser line was employed. Further development of this system to accommodate up to 4096 independent sequencing channels at a time is discussed. 26 refs., 6 figs., 2 tabs.

It is desirable to observe signals due to analyte species in the total ion current (TIC) electropherogram for detection purposes. We report a combination of broad-band collisional activation and resonance ejection that is useful in improving signal/background and signal/noise ratios in TIC electropherograms obtained with capillary electrophoresis coupled with a quadrupole ion trap. This combined approach allows for the acquisition of mass spectra over a wide mass/charge range with improved ability to observe analyte peaks following low-level injections. 24 refs., 4 figs.

A single intact red blood cell (erythrocyte) was injected into a capillary electrophoresis column, and following in-capillary lysing the alpha- and beta-chains of the hemoglobin (approximately 450 amol) were separated and detected using capillary electrophoresis/electrospray ionization time-of-flight mass spectrometry. The mass specta of the electropherogram peaks of the alpha and beta chains showed identifiable peaks corresponding to multiply protonated and sodiated alpha- and beta-chains of hemoglobin.

We introduce a novel electrophoretic method, nonequilibrium capillary electrophoresis of equilibrium mixtures (NECEEM), and demonstrate its use for studying protein-DNA interactions. The equilibrium mixture of protein and DNA contains three components: free protein, free DNA, and the protein-DNA complex. A short plug of such a mixture is injected into the capillary, and the three components are separated under nonequilibrium conditions. The resulting electropherograms are composed of characteristic peaks and exponential curves. An easy nonnumerical analysis of a single electropherogram reveals two parameters: the equilibrium binding constant and the monomolecular rate constant of complex decay. The bimolecular rate constant of complex formation can then be calculated as the product of the two experimentally determined constants. NECEEM was applied to study the interaction between single-stranded DNA binding protein and a fluorescently labeled 15-mer oligonucleotide. It allowed us to measure for the first time the rate constant of complex decay for this important protein-DNA pair, k-1 = 0.03 s-1. The value of the equilibrium binding constant, Kb = 3.6 x 10-6 M-1, was in good agreement with those measured by other methods. As low as 10-18 mol of the protein was sufficient for the measurements. Thus, the new method is simple, informative, and highly sensitive. Moreover, it can be equally applied to other noncovalent protein-ligand complexes. These features of NECEEM make this method an indispensable tool in studies of macromolecular interactions. They also emphasize the potential role of NECEEM in the development of extremely sensitive protein assays using nucleotide aptamers.

"Ligand" or "binding" assays have made a major impact on biomedical research and clinical diagnosis since their development in the late 1950s. Immunoassay techniques (relying on specific antibodies to bind the target analyte) represent the best-known example, but analogous DNA and RNA analysis methods (using oligonucleotides to recognize defined polynucleotide sequences) are rapidly gaining in importance and are likely to exert profound effects on human society. The evolution of these methods may be divided into three phases: (i) the initial development and widespread use of sensitive "competitive" assays relying on radioisotopically labeled analyte to monitor the binding reaction; (ii) the introduction in the 1980s of "ultrasensitive", "noncompetitive", labeled antibody methods relying on high-specific-activity nonisotopic labels, leading to the emergence of the automatic analyzers that now dominate the field, and (iii) the present development of "microarray"methods based on antibody or oligonucleotide microspots (each recognizing an individual analyte) arrayed on a solid support and relying on observation (typically by confocal microscopy) of fluorescent signals emitted from each spot. Miniaturized microarray methods permitting ultrasensitive measurement of hundreds of different analytes in a minute sample are likely to revolutionize medicine and related fields within the next decade.