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56-642: Livia S. Eberlin , Ph.D., an Assistant Professor of Chemistry at the University of Texas at Austin , first reported the invention of the MasSpec Pen in 2017. Within her laboratory, the device has been used to analyze human tissue biopsies, including normal and cancerous breast, lung, ovarian, and thyroid samples. The MasSpec Pen is currently being evaluated for use on freshly excised tissue biopsies and for intraoperative use during oncology surgeries. The MasSpec Pen has been licensed to Genio Technologies, Inc.,

112-414: A calibration curve . This allows for the determination of the amount of a chemical in a material by comparing the results of an unknown sample to those of a series of known standards. If the concentration of element or compound in a sample is too high for the detection range of the technique, it can simply be diluted in a pure solvent. If the amount in the sample is below an instrument's range of measurement,

168-699: A transistor due to base current, and so on. This noise can be avoided by modulation of the signal at a higher frequency, for example, through the use of a lock-in amplifier . Environmental noise arises from the surroundings of the analytical instrument. Sources of electromagnetic noise are power lines , radio and television stations, wireless devices , compact fluorescent lamps and electric motors . Many of these noise sources are narrow bandwidth and, therefore, can be avoided. Temperature and vibration isolation may be required for some instruments. Noise reduction can be accomplished either in computer hardware or software . Examples of hardware noise reduction are

224-559: A chemical present in blood that increases the risk of cancer would be a discovery that an analytical chemist might be involved in. An effort to develop a new method might involve the use of a tunable laser to increase the specificity and sensitivity of a spectrometric method. Many methods, once developed, are kept purposely static so that data can be compared over long periods of time. This is particularly true in industrial quality assurance (QA), forensic and environmental applications. Analytical chemistry plays an increasingly important role in

280-442: A combination of two (or more) techniques to detect and separate chemicals from solutions. Most often the other technique is some form of chromatography . Hyphenated techniques are widely used in chemistry and biochemistry . A slash is sometimes used instead of hyphen , especially if the name of one of the methods contains a hyphen itself. The visualization of single molecules, single cells, biological tissues, and nanomaterials

336-540: A discrete water droplet to extract biomolecules from the tissue's surface and transporting them to a mass spectrometer for molecular analysis. The pen allows surgeons to achieve a better understanding of which tissues should be removed. As a co-principal investigator at the University of Texas at Austin, Eberlin has developed a method to detect thyroid cancer using Desorption electrospray ionization mass spectrometry (DESI-MS) imaging of fine-needle aspiration biopsies. It

392-408: A function, we may also want to calculate the error of the function. Let f {\displaystyle f} be a function with N {\displaystyle N} variables. Therefore, the propagation of uncertainty must be calculated in order to know the error in f {\displaystyle f} : A general method for analysis of concentration involves the creation of

448-412: A probe that can be manipulated by hand to direct the analysis. To use the system, the tip of the 'pen' is placed in contact with the surface to be sampled and the user triggers the initiation of a sampling procedure by pressing an integrated foot pedal. This signals a syringe pump to deliver a small aliquot of solvent through a polymer tube to a reservoir at the tip of the 'pen' that remains in contact with

504-466: A sample surface that are subsequently analyzed by a mass spectrometer. Desorption electrospray ionization (DESI) was the first liquid-based ambient ionization MS method. DESI employed a spray of charged solvent droplets to bombard a sample surface to desorb and ionize molecules from the sample surface, which are then directed towards and analyzed by a mass spectrometer. DESI-MS and other solvent-based ambient ionization MS methods has been widely employed for

560-495: A single chip of only millimeters to a few square centimeters in size and that are capable of handling extremely small fluid volumes down to less than picoliters. Error can be defined as numerical difference between observed value and true value. The experimental error can be divided into two types, systematic error and random error. Systematic error results from a flaw in equipment or the design of an experiment while random error results from uncontrolled or uncontrollable variables in

616-440: A subsidiary of MS Pen Technologies, Inc. The MasSpec Pen technology is based on the principles of ambient ionization , in which ions are generated directly from a sample without need for extensive sample preparation or chromatographic separations. The MasSpec Pen can further be categorized as a solid-liquid extraction based ambient ionization method, described as methods that utilize a solvent system to gently extract molecules from

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672-462: A systematic scheme to confirm the presence of certain aqueous ions or elements by performing a series of reactions that eliminate a range of possibilities and then confirm suspected ions with a confirming test. Sometimes small carbon-containing ions are included in such schemes. With modern instrumentation, these tests are rarely used but can be useful for educational purposes and in fieldwork or other situations where access to state-of-the-art instruments

728-499: A wide variety of reactions. The late 20th century also saw an expansion of the application of analytical chemistry from somewhat academic chemical questions to forensic , environmental , industrial and medical questions, such as in histology . Modern analytical chemistry is dominated by instrumental analysis. Many analytical chemists focus on a single type of instrument. Academics tend to either focus on new applications and discoveries or on new methods of analysis. The discovery of

784-479: Is an important and attractive approach in analytical science. Also, hybridization with other traditional analytical tools is revolutionizing analytical science. Microscopy can be categorized into three different fields: optical microscopy , electron microscopy , and scanning probe microscopy . Recently, this field is rapidly progressing because of the rapid development of the computer and camera industries. Devices that integrate (multiple) laboratory functions on

840-532: Is categorized by approaches of mass analyzers: magnetic-sector , quadrupole mass analyzer , quadrupole ion trap , time-of-flight , Fourier transform ion cyclotron resonance , and so on. Electroanalytical methods measure the potential ( volts ) and/or current ( amps ) in an electrochemical cell containing the analyte. These methods can be categorized according to which aspects of the cell are controlled and which are measured. The four main categories are potentiometry (the difference in electrode potentials

896-458: Is increasing. An interest towards absolute (standardless) analysis has revived, particularly in emission spectrometry. Great effort is being put into shrinking the analysis techniques to chip size. Although there are few examples of such systems competitive with traditional analysis techniques, potential advantages include size/portability, speed, and cost. (micro total analysis system (μTAS) or lab-on-a-chip ). Microscale chemistry reduces

952-550: Is measured), coulometry (the transferred charge is measured over time), amperometry (the cell's current is measured over time), and voltammetry (the cell's current is measured while actively altering the cell's potential). Calorimetry and thermogravimetric analysis measure the interaction of a material and heat . Separation processes are used to decrease the complexity of material mixtures. Chromatography , electrophoresis and field flow fractionation are representative of this field. Chromatography can be used to determine

1008-434: Is not available or expedient. Quantitative analysis is the measurement of the quantities of particular chemical constituents present in a substance. Quantities can be measured by mass (gravimetric analysis) or volume (volumetric analysis). The gravimetric analysis involves determining the amount of material present by weighing the sample before and/or after some transformation. A common example used in undergraduate education

1064-400: Is the bandwidth of the frequency f {\displaystyle f} . Shot noise is a type of electronic noise that occurs when the finite number of particles (such as electrons in an electronic circuit or photons in an optical device) is small enough to give rise to statistical fluctuations in a signal. Shot noise is a Poisson process , and the charge carriers that make up

1120-619: Is the daughter of Marcos Nogueira Eberlin , a Brazilian chemist at the University of Campinas . She was born in Campinas , and she earned her bachelor's degree in 2007 from the University of Campinas. During her undergraduate studies, she did summer research in mass spectrometry at Purdue University , where her father also had research ties. She later enrolled at Purdue for her doctorate, which she completed in 2012. Her dissertation, Developments in ambient mass spectrometry imaging and its applications in biomedical research and cancer diagnosis ,

1176-414: Is the determination of the amount of water in a hydrate by heating the sample to remove the water such that the difference in weight is due to the loss of water. Titration involves the gradual addition of a measurable reactant to an exact volume of a solution being analyzed until some equivalence point is reached. Titrating accurately to either the half-equivalence point or the endpoint of a titration allows

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1232-426: Is two-thirds more accurate than the test already in use, fine-needle aspiration, which yields more indeterminate results when used in isolation. In addition to her work on cancer diagnosis, Eberlin has also worked with Cooks and her father on the use of mass spectrometry to quickly detect counterfeit money . Eberlin is concerned about the representation of women and diversity in science. In interviews, she has stressed

1288-423: Is used instead of a calibration curve to solve the matrix effect problem. One of the most important components of analytical chemistry is maximizing the desired signal while minimizing the associated noise . The analytical figure of merit is known as the signal-to-noise ratio (S/N or SNR). Noise can arise from environmental factors as well as from fundamental physical processes. Thermal noise results from

1344-923: The Moore Inventor Fellowship in 2018. She received the 2020 Curt Brunnée Award from the International Mass Spectrometry Foundation . She was named on the Power List by the Analytical Scientist in 2014, 2018, 2019, 2021, 2022, 2023, and 2024. She received the 2024 Norman Hackerman Award from the Welch Foundation . Analytical chemistry Analytical chemistry studies and uses instruments and methods to separate , identify, and quantify matter. In practice, separation, identification or quantification may constitute

1400-422: The amounts of chemicals used. Many developments improve the analysis of biological systems. Examples of rapidly expanding fields in this area are genomics , DNA sequencing and related research in genetic fingerprinting and DNA microarray ; proteomics , the analysis of protein concentrations and modifications, especially in response to various stressors, at various developmental stages, or in various parts of

1456-532: The analysis of small molecules, primarily metabolites and lipids, directly from biological tissue specimens to determine their molecular composition and leverage the mass spectral data acquired for diagnostic purposes. These methods have been deployed for the discrimination of normal and cancerous regions of tissue samples for many solid tumor indications, including breast, brain, prostate, ovarian, and colorectal, among others. Multivariate statistical analysis methods are often utilized to generate statistical models from

1512-426: The authors demonstrated the use of this method for in vivo analysis of tumor tissues using an anesthetized murine model. Performance of the MasSpec Pen for ovarian cancer diagnosis was further evaluated in a report published in 2019. The authors analyzed 160 human ovarian tissue samples, including 78 normal ovary and 82 serous carcinomas, with the MasSpec Pen and developed classification models to discriminate between

1568-512: The backbone of most undergraduate analytical chemistry educational labs. Qualitative analysis determines the presence or absence of a particular compound, but not the mass or concentration. By definition, qualitative analyses do not measure quantity. There are numerous qualitative chemical tests, for example, the acid test for gold and the Kastle-Meyer test for the presence of blood . Inorganic qualitative analysis generally refers to

1624-483: The breast tissues with 95.6% accuracy, lung with 96.8% accuracy, and ovary with 94.7% accuracy. Statistical models also allowed for the discrimination of normal thyroid from papillary thyroid carcinomas with 97.8% accuracy and from follicular thyroid adenomas with 94.7% accuracy. The report also demonstrated the ability of the MasSpec Pen technology to detect cancer within regions of mixed tissue containing both normal and cancerous cells from an ovarian cancer sample. Finally,

1680-490: The chemist to determine the amount of moles used, which can then be used to determine a concentration or composition of the titrant. Most familiar to those who have taken chemistry during secondary education is the acid-base titration involving a color-changing indicator, such as phenolphthalein . There are many other types of titrations, for example, potentiometric titrations or precipitation titrations. Chemists might also create titration curves in order by systematically testing

1736-438: The current follow a Poisson distribution . The root mean square current fluctuation is given by where e is the elementary charge and I is the average current. Shot noise is white noise. Flicker noise is electronic noise with a 1/ ƒ frequency spectrum; as f increases, the noise decreases. Flicker noise arises from a variety of sources, such as impurities in a conductive channel, generation, and recombination noise in

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1792-420: The discrimination of cancer from fallopian tube and peritoneum tissues, respectively. The MasSpec Pen has also been implemented for the detection of pancreatic cancer during excision procedures. The MasSpec Pen was used on both ex vivo and in vivo tissue samples to discriminate between healthy pancreas and pancreatic tumor tissue. The device was also used to detect cancerous margins near adjacent structures of

1848-649: The early 20th century and refined in the late 20th century. The separation sciences follow a similar time line of development and also became increasingly transformed into high performance instruments. In the 1970s many of these techniques began to be used together as hybrid techniques to achieve a complete characterization of samples. Starting in the 1970s, analytical chemistry became progressively more inclusive of biological questions ( bioanalytical chemistry ), whereas it had previously been largely focused on inorganic or small organic molecules . Lasers have been increasingly used as probes and even to initiate and influence

1904-405: The early days of chemistry, providing methods for determining which elements and chemicals are present in the object in question. During this period, significant contributions to analytical chemistry included the development of systematic elemental analysis by Justus von Liebig and systematized organic analysis based on the specific reactions of functional groups. The first instrumental analysis

1960-830: The entire analysis or be combined with another method. Separation isolates analytes . Qualitative analysis identifies analytes, while quantitative analysis determines the numerical amount or concentration. Analytical chemistry consists of classical, wet chemical methods and modern, instrumental methods . Classical qualitative methods use separations such as precipitation , extraction , and distillation . Identification may be based on differences in color, odor, melting point, boiling point, solubility, radioactivity or reactivity. Classical quantitative analysis uses mass or volume changes to quantify amount. Instrumental methods may be used to separate samples using chromatography , electrophoresis or field flow fractionation . Then qualitative and quantitative analysis can be performed, often with

2016-513: The experiment. In error the true value and observed value in chemical analysis can be related with each other by the equation where An error of a measurement is an inverse measure of accurate measurement, i.e. smaller the error greater the accuracy of the measurement. Errors can be expressed relatively. Given the relative error( ε r {\displaystyle \varepsilon _{\rm {r}}} ): The percent error can also be calculated: If we want to use these values in

2072-839: The importance of women in higher levels of academia as well as leadership. Eberlin was named among the Forbes "30 Under 30" list in 2015. She won the Marion Milligan Mason Award of the American Association for the Advancement of Science in 2016. The award is given every two years to promising young female researchers in chemistry. She won the MacArthur "Genius" Fellowship from the John D. and Catherine T. MacArthur Foundation in 2018 for her research on

2128-467: The internal standard as a calibrant. An ideal internal standard is an isotopically enriched analyte which gives rise to the method of isotope dilution . The method of standard addition is used in instrumental analysis to determine the concentration of a substance ( analyte ) in an unknown sample by comparison to a set of samples of known concentration, similar to using a calibration curve . Standard addition can be applied to most analytical techniques and

2184-693: The main branches of contemporary analytical atomic spectrometry, the most widespread and universal are optical and mass spectrometry. In the direct elemental analysis of solid samples, the new leaders are laser-induced breakdown and laser ablation mass spectrometry, and the related techniques with transfer of the laser ablation products into inductively coupled plasma . Advances in design of diode lasers and optical parametric oscillators promote developments in fluorescence and ionization spectrometry and also in absorption techniques where uses of optical cavities for increased effective absorption pathlength are expected to expand. The use of plasma- and laser-based methods

2240-414: The mass spectral data acquired from direct analysis of tissue samples to distinguish between healthy and diseased tissues. The MasSpec Pen, initially described in 2017, is a solvent-based ambient ionization technique but differs from its predecessors due to the handheld nature of the device, allowing analysis of samples distant from the mass spectrometer in a geometry independent manner. The MasSpec Pen used

2296-519: The mass spectrometer analyzer and the mass spectrum resulting is generated. The MasSpec Pen was designed to assist in the detection of positive surgical margins during solid tumor debulking procedures to assist in the complete excision of cancer surgeries. The device was initially used to analyze 253 human tissue biopsies, including normal and cancerous breast, lung, ovary, and thyroid tissues. The mass spectra obtained for each sample contained metabolites, lipids, and some proteins that were representative of

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2352-424: The method of addition can be used. In this method, a known quantity of the element or compound under study is added, and the difference between the concentration added and the concentration observed is the amount actually in the sample. Sometimes an internal standard is added at a known concentration directly to an analytical sample to aid in quantitation. The amount of analyte present is then determined relative to

2408-690: The migration distance of the solvent front during chromatography. In combination with the instrumental methods, chromatography can be used in quantitative determination of the substances. Combinations of the above techniques produce a "hybrid" or "hyphenated" technique. Several examples are in popular use today and new hybrid techniques are under development. For example, gas chromatography-mass spectrometry , gas chromatography- infrared spectroscopy , liquid chromatography-mass spectrometry , liquid chromatography- NMR spectroscopy , liquid chromatography-infrared spectroscopy, and capillary electrophoresis-mass spectrometry. Hyphenated separation techniques refer to

2464-423: The molecular composition of the tissue analyzed. The collected data for each tissue type was then used to develop statistical models that could discriminate between the normal and cancer samples of each tissue type. Leave-one-patient-out cross validation was used to evaluate the accuracy of the models for distinguishing the normal and cancer tissues based on their molecular profiles. The method allowed for diagnosis of

2520-523: The motion of charge carriers (usually electrons) in an electrical circuit generated by their thermal motion. Thermal noise is white noise meaning that the power spectral density is constant throughout the frequency spectrum . The root mean square value of the thermal noise in a resistor is given by where k B is the Boltzmann constant , T is the temperature , R is the resistance, and Δ f {\displaystyle \Delta f}

2576-461: The normal and cancer samples. The model was able to distinguish between the normal and cancerous ovarian samples with 98.3%, 100.0%, and 92.3% overall accuracy on a training, validation, and test set of samples. Further, the report evaluated the ability of the MasSpec Pen system to distinguish ovarian cancer from fallopian tube and peritoneum tissue, two of the most common sites for ovarian cancer metastasis. Accuracies of 87.9% and 92.6% were achieved for

2632-896: The pH every drop in order to understand different properties of the titrant. Spectroscopy measures the interaction of the molecules with electromagnetic radiation . Spectroscopy consists of many different applications such as atomic absorption spectroscopy , atomic emission spectroscopy , ultraviolet-visible spectroscopy , X-ray spectroscopy , fluorescence spectroscopy , infrared spectroscopy , Raman spectroscopy , dual polarization interferometry , nuclear magnetic resonance spectroscopy , photoemission spectroscopy , Mössbauer spectroscopy and so on. Mass spectrometry measures mass-to-charge ratio of molecules using electric and magnetic fields . There are several ionization methods: electron ionization , chemical ionization , electrospray ionization , fast atom bombardment, matrix-assisted laser desorption/ionization , and others. Also, mass spectrometry

2688-476: The pancreas such as the bile duct. The system was used in 18 pancreatic cancer surgeries and the data collected allowed the detection of cancerous tissue with high accuracy. Livia S. Eberlin Livia Schiavinato Eberlin is a Brazilian analytical chemist who won a MacArthur "Genius" Fellowship for her research on the use of mass spectrometry to detect cancerous tissue. Eberlin

2744-491: The pharmaceutical industry where, aside from QA, it is used in the discovery of new drug candidates and in clinical applications where understanding the interactions between the drug and the patient are critical. Although modern analytical chemistry is dominated by sophisticated instrumentation, the roots of analytical chemistry and some of the principles used in modern instruments are from traditional techniques, many of which are still used today. These techniques also tend to form

2800-409: The presence of substances in a sample as different components in a mixture have different tendencies to adsorb onto the stationary phase or dissolve in the mobile phase. Thus, different components of the mixture move at different speed. Different components of a mixture can therefore be identified by their respective R ƒ values , which is the ratio between the migration distance of the substance and

2856-458: The same instrument and may use light interaction , heat interaction , electric fields or magnetic fields . Often the same instrument can separate, identify and quantify an analyte. Analytical chemistry is also focused on improvements in experimental design , chemometrics , and the creation of new measurement tools. Analytical chemistry has broad applications to medicine, science, and engineering. Analytical chemistry has been important since

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2912-459: The sample. Analytes are then extracted from the sample into the solvent droplet by a solid-liquid extraction mechanism. After a 3 second extraction period, the droplet is aspirated into the mass spectrometer using the vacuum from the mass spectrometer as the vacuum source. Once inside the mass spectrometer, the analytes within the solvent droplet are de-solvated and ionized via an inlet ionization mechanism. The ionized molecules are then analyzed by

2968-610: The use of shielded cable , analog filtering , and signal modulation. Examples of software noise reduction are digital filtering , ensemble average , boxcar average, and correlation methods. Analytical chemistry has applications including in forensic science , bioanalysis , clinical analysis , environmental analysis , and materials analysis . Analytical chemistry research is largely driven by performance (sensitivity, detection limit , selectivity, robustness, dynamic range , linear range , accuracy, precision, and speed), and cost (purchase, operation, training, time, and space). Among

3024-466: The use of mass spectrometry "to differentiate more quickly and accurately diseased from healthy tissues during surgery". She is the first UT Austin professor to win MacArthur grant this century. The award consists of a $ 625,000 no-strings-attached grant. According to the foundation, this award goes to "extraordinarily talented and creative individuals as an investment in their potential". She also won

3080-404: Was flame emissive spectrometry developed by Robert Bunsen and Gustav Kirchhoff who discovered rubidium (Rb) and caesium (Cs) in 1860. Most of the major developments in analytical chemistry took place after 1900. During this period, instrumental analysis became progressively dominant in the field. In particular, many of the basic spectroscopic and spectrometric techniques were discovered in

3136-511: Was supervised by R. Graham Cooks . After postdoctoral research at Stanford University with Richard Zare , she joined the faculty at the University of Texas at Austin in 2015 in the Department of Chemistry. She joined Baylor College of Medicine as Associate Professor in 2021. Eberlin developed a pen-like device, called the "MasSpec Pen" or "The Cancer Pen", that has demonstrated the capability to detect cancerous tissue by delivering

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