Research

We present a programmable device—scanning pH-meter—that can automatically generate different types of pH ramps/waveforms in a solution. It can be used to explore reversibility of protein folding.

Fizzy extraction (FE) is an extraction technique that extracts volatile organic compounds (VOCs) from liquid matrices using pressure-induced effervescence. We coupled FE with an atmospheric pressure chemical ionization interface of a quadrupole time-of-flight mass spectrometry system to perform analysis of VOCs present in whiskeys. The resulting method was applied in analysis of 40 whiskeys originating from different countries or distilleries. The VOC profiles were used to characterize the whiskeys’ quality and age. [read more]

We have developed an analytical system incorporating data acquisition by an ion-mobility spectrometer, data transmission, centralized data analysis, and visualization in real time. [read more]

To carry out simultaneous monitoring of analytes with different ionogenic moieties by electrospray ionization mass spectrometry, a rapid acid/base switching system was developed. The system was further coupled with flow injection analysis and liquid chromatography mass spectrometry. The two variants enable detection of separated analytes immediately after alternating addition of acid and base. [read more]

We demonstrate low-frequency-sound-modulated electrospray ionization for analysis of biomolecules. By using a low-frequency (50–350 Hz) sound, it is possible to deflect electrospray microdroplets toward the mass spectrometer’s orifice. [read more]

A portable platform for analysis of volatiles in liquid samples is disclosed. It is based on hyphenation of fizzy extraction and ion-mobility spectrometry. [read more]

We demonstrate a new skin metabolite analysis method utilizing a flat disc-shaped sampling probe, and a compatible re-extraction apparatus coupled online with extractive electrospray ionization mass spectrometry. Skin metabolite analysis can be an alternative and non-invasive way of clinical diagnostics. [read more]

Telechemistry 2.0: An open-source system developed for remote monitoring of fluorescent chemical reactions. The device can be easily built using inexpensive off-the-shelf electronic components, optical fibers, and 3D-printed components. The system also incorporates auxiliary sensors to measure relative alcohol vapor concentration, temperature, and humidity at different locations in the laboratory. [read more]

We have developed BioChemPen, a portable wireless biosensor device for rapid analysis of substances adsorbed on solid surfaces. It takes advantage of (bio)luminescent reactions in a hydrogel matrix. It can be used to detect bleach on cleaned surfaces, ATP in meat, or pesticides on foodstuffs. [read more]

The team presents catalytic oxygenation-mediated extraction (COME) for rapid analysis of volatile solutes. It takes advantage of biocatalytic production of oxygen occurring directly in the sample. The newly formed oxygen (micro)bubbles extract the dissolved volatile organic compounds. Subsequently, the gaseous extract is transferred to a separation or detection system. The COME apparatus incorporates a simple electronic control system. It has been hyphenated with gas chromatography, mass spectrometry, and ion-mobility spectrometry. [read more]

We present a new approach for chemical mapping, which focuses on volatile organic compounds (VOCs). This task has been challenging due to the high diffusivities and low concentrations of VOCs in the gas phase. The presented approach benefits from the high selectivity of mass spectrometry. It also takes advantage of simple robotics and open-source prototyping tools. The platform has been used to map several specimens representing various matrices and application areas. [read more]

We have developed a portable cloud-integrated pen-probe analyzer, based on ion-mobility spectrometry, for in-situ analysis of volatile organic compounds emanating from surfaces. It is capable of semi-automated sample collection, immediate data processing, and uploading results online. It was used to record spectra of real matrices such as foodstuffs. [read more]

In the recent report, we discuss the usefulness of sample flow rate scan in the studies related to protein mass spectrometry. Ramping sample flow rate during mass spectrometric analysis reveals alterations to protein ion charge state distributions. [read more]

The Urban Lab has published a protocol for the use of inexpensive electronic modules in chemistry and biochemistry research. [read more]

Effervescent tablets are used to transfer volatile organic compounds (VOCs) from liquid to gas phase within seconds. This seamless sample preparation is followed by mass spectrometric or gas chromatographic detection. The method is suitable for analysis of volatile solutes in complex samples (e.g. beverages and cosmetics). [read more]

Dual sample chamber mass spectrometry system has been developed to follow the release of volatile organic compounds (VOCs) from various organic specimens. The method enables monitoring VOC emanations that accompany microbial growth, fungal morphogenesis, and putrefaction. [read more]

The technique of fizzy extraction (invented in our laboratory three years ago) has been coupled with gas chromatography. This hyphenated approach enables fast, sensitive, and selective analysis of volatile organic compounds (VOCs) present in various types of liquid samples. [read more]

In a recent study, we demonstrated biochemical assays enabled by droplet actuation with acoustic wave. Tiny droplets containing samples and reagents are dispensed onto a hydrophobic thread, moved with the aid of sound, merged, and the reaction product is monitored in real time by a mini-spectrometer. [read more]

The newly developed analytical method allows researchers to study protein folding in response to rapidly changing pH. An autocatalytic enzymatic reaction is employed to ramp up pH. At the same time, alterations to target protein conformation are monitored by mass spectrometry or fluorometry. [read more]

Our team has introduced gel-phase microextraction technique for seamless sampling of analytes adsorbed on surfaces prior to mass spectrometric analysis. [read more]

We have developed a flow rate scanner comprising a pump, an inexpensive single-board computer, and an associated Python program. The device enables fast characterization of on-line detection systems (e.g. mass spectrometers). [read more]

In a recent study on fizzy extraction, we meticulously investigated this technique with the aim to characterize the extraction mechanism. The results presented in the related report can help analysts to predict the occurrence of matrix effects when analyzing real samples. They also provide a basis for increasing extraction efficiency to detect low-abundance analytes. [read more]