Abstract: The present disclosure is notably directed to a microfluidic probe head (202), or MFP head, comprising a processing surface (204) having liquid injection and liquid aspiration apertures, as well as projections (205) extending from the processing surface (204). The arrangement of injection and aspiration apertures provides for a hydrodynamic flow confinement within a processing region that is formed between the processing surface (204) and a substrate (104) or sample surface (for example, the bottom of a microtiter plate sample well (102)), typically located beneath the processing surface (204). The disclosure is further directed to related microfluidic probe devices, and methods of operation of such an MFP head, notably to deposit cells on a surface.

Abstract: The present disclosure is notably directed to a microfluidic probe head, or MFP head, comprising a processing surface having a liquid injection aperture and a liquid aspiration aperture thereon. The aspiration aperture is generally shaped so as to partly extend around the injection aperture on the processing surface, although such injection apertures are not completely surrounded by the slit on the processing surface. Further, fluidic and solid barriers to aspiration are considered. The disclosure is further directed to related microfluidic probe devices, and methods of operation of such an MFP head, notably to deposit cells on a surface.

Abstract: Techniques regarding measuring a position and transcriptome of one or more cells from a biological sample are provided. For example, one or more embodiments described herein can comprise a method, which can comprise covalently bonding a probe to a molecular structure located on a cell to label the cell according to a position of the cell with regards to a biological sample comprising the cell. The probe comprises an oligonucleotide sequence that can be indicative of the position.

Abstract: The present disclosure is notably directed to a microfluidic probe head, or MFP head, comprising a processing surface having a liquid injection aperture and a liquid aspiration aperture thereon. The aspiration aperture is generally shaped so as to partly extend around the injection aperture on the processing surface, although such injection apertures are not completely surrounded by the slit on the processing surface. Further, fluidic and solid barriers to aspiration are considered. The disclosure is further directed to related microfluidic probe devices, and methods of operation of such an MFP head, notably to deposit cells on a surface.

Abstract: The present disclosure is notably directed to a microfluidic probe head (202), or MFP head, comprising a processing surface (204) having liquid injection and liquid aspiration apertures, as well as projections (205) extending from the processing surface (204). The arrangement of injection and aspiration apertures provides for a hydrodynamic flow confinement within a processing region that is formed between the processing surface (204) and a substrate (104) or sample surface (for example, the bottom of a microtiter plate sample well (102)), typically located beneath the processing surface (204). The disclosure is further directed to related microfluidic probe devices, and methods of operation of such an MFP head, notably to deposit cells on a surface.

Abstract: Techniques regarding measuring a position and transcriptome of one or more cells from a biological sample are provided. For example, one or more embodiments described herein can comprise a method, which can comprise covalently bonding a probe to a molecular structure located on a cell to label the cell according to a position of the cell with regards to a biological sample comprising the cell. The probe comprises an oligonucleotide sequence that can be indicative of the position.

Abstract: Methods and systems are provided for characterizing responses of a ligand-functionalized surface, which rely on dispensing a segmented liquid flow including liquid sequences, each including: an analyte segment including biomolecules of analyte; a spacer segment; and a wash segment including a washing liquid, whereby spacer segments separate wash segments from analyte segments in the dispensed segmented liquid flow. A measurement cycle is performed for each of the liquid sequences of the segmented liquid flow being dispensed. A measurement cycle includes: ejecting an analyte segment of each liquid sequence toward the ligand-functionalized surface and extracting, from each liquid sequence, a spacer segment succeeding the analyte segment as the latter is being ejected; ejecting a wash segment succeeding the extracted spacer segment in each liquid sequence to flush unbound and/or weakly bound biomolecules of analytes from the surface; and reading out a signal of bound biomolecules of analytes on the surface.

Abstract: Methods and systems are provided for characterizing responses of a ligand-functionalized surface, which rely on dispensing a segmented liquid flow including liquid sequences, each including: an analyte segment including biomolecules of analyte; a spacer segment; and a wash segment including a washing liquid, whereby spacer segments separate wash segments from analyte segments in the dispensed segmented liquid flow. A measurement cycle is performed for each of the liquid sequences of the segmented liquid flow being dispensed. A measurement cycle includes: ejecting an analyte segment of each liquid sequence toward the ligand-functionalized surface and extracting, from each liquid sequence, a spacer segment succeeding the analyte segment as the latter is being ejected; ejecting a wash segment succeeding the extracted spacer segment in each liquid sequence to flush unbound and/or weakly bound biomolecules of analytes from the surface; and reading out a signal of bound biomolecules of analytes on the surface.

Abstract: Indirect detection and/or identification of analytes by ITP can be enhanced by adding a mixture of labeled carrier ampholytes (CAs) to the sample to provide a continuous range of mobility markers. Each analyte can be detected and quantified by corresponding gaps in the CA signal. This approach does not require a priori choice of fluorophores and can be readily applied (without extensive and specific design) to a wide range of analytes. Analyte identification can be expedited by computing a normalized signal integral (NSI) from the CA signals. Empirical calibrations can relate the NSI to effective mobility. Effective mobility results under two or more different pH conditions can be used to determine analyte pKa and fully ionized mobility, which are analyte properties that can facilitate analyte identification.

Abstract: Indirect detection and/or identification of analytes by ITP can be enhanced by adding a mixture of labeled carrier ampholytes (CAs) to the sample to provide a continuous range of mobility markers. Each analyte can be detected and quantified by corresponding gaps in the CA signal. This approach does not require a priori choice of fluorophores and can be readily applied (without extensive and specific design) to a wide range of analytes. Analyte identification can be expedited by computing a normalized signal integral (NSI) from the CA signals. Empirical calibrations can relate the NSI to effective mobility. Effective mobility results under two or more different pH conditions can be used to determine analyte pKa and fully ionized mobility, which are analyte properties that can facilitate analyte identification.