One-Dimensional Nanoprobes for Single-Cell Studies

Abstract

Owing to variation of individual cells within a population, single-cell studies are of great interest to researchers. Recent developments in nanofabrication technology have made this area increasingly attractive as one-dimensional (1D) nanoscale probes can be manufactured with increasing accuracy. Here, we provide an overview and description of the major designs that have been reported to date. For more details of what applications could be realized and how, based on the probe shapes and designs, we summarize the most recently reported performances of 1D single-cell probes with their advantages and limitations. Minimally invasive probes are required for long-term experiments on single cells. Carbon nanotubes with their unique properties and structure are excellent candidates for multitask robotic intracellular probes. Carbon nanotube-tipped cellular endoscopes are less invasive compared with pipettes or cantilever tips. Advances in nanofabrication techniques have made it possible to produce more consistent nanoscale cellular probes that can capture a variety of information from optical, electrical and chemical signals. In addition, these tools can transfer tiny amounts of fluids and molecular materials in a highly localized fashion for the purpose of analyzing or stimulating a variety of responses at the level of individual cells and even cellular organelles. We conclude with a critical analysis of the current state of the field as well as the major obstacles for further probe development of minimally invasive probes and their widespread use in cell biology.

Voyage inside the cell: Microsystems and nanoengineering for intracellular measurement and manipulation

“…In addition to nanowires, CNTs are also used for intracellular electrical recording 40 . A CNT is a tube-shaped nanostructure made of carbon atoms, with a diameter on the scale of nanometers and a high aspect ratio 41 .…”

Perfusion double-channel micropipette probes for oxygen flux mapping with single-cell resolution

“…An alternative approach is to map concentration gradients using scanning probes that may employ some means of sensing such as electrochemical or optical [ 8 – 15 ]. These types of probes can attain subcellular scale resolution when their tip size is smaller than the size of a cell [ 10 – 11 ]. However, the sensitivity of most sensors is typically proportional to their effective area, so sensors with relatively higher spatial resolution have lower sensitivity [ 14 – 16 ], or require a drastically increased measurement time.…”

High‐Efficiency Gene Transfection of Cells through Carbon Nanotube Arrays

“…The most common methods used for transfecting mammalian cells include: Lipofection, which is simple but can have high toxicity and variable efficiency, particularly for post mitotic cells; Electroporation, which requires significant investment in hardware and has variable efficiency and significant toxicity; Viral vectors, which are labor intensive to construct, can have high toxicity at high titers (necessary for increased efficiency) and have a limited DNA packing size; Biolistics (Gene Gun), which can transfer multiple species of DNA but requires expensive hardware and has low efficiency and high toxicity. Intracellular microinjection has also been used for gene transfection and other delivery applications, either through glass micropipettes or hollow nanostructures . However, microinjection is carried out in a serial fashion, making it very time‐consuming, even with automated systems …”

“…Intracellular microinjection has also been used for gene transfection and other delivery applications, either through glass micropipettes [ 5 ] or hollow nanostructures. [6][7][8][9][10][11][12] However, microinjection is carried out in a serial fashion, making it very time-consuming, even with automated systems. [ 13,14 ] Recently, arrays of vertically aligned nanostructures have been developed for cell transfection.…”