旭月科技

What is NMT?

NMT is also capable of obtaining ionic/molecular fluxes in 3D by measuring the concentration gradient in all x, y and z directions.	Non-invasive Micro-test Technology (NMT® ) is developed based on the ‘vibrating probe’ technique started by Dr. Lionel Jaffe from Marine Biological Laboratory, Woods Hole, Massachusetts and Dr. Ian Newman from Tasmania University of Australia in the early 1990s (please see literatures here). Without touching the samples, NMT is able to tell researchers how fast specific ions and/or molecules are going in or coming out their living samples.
	NMT will detect ionic/molecular fluxes (up to pico(10^-12)molescm^-2s^-1） in liquid media near the surface of samples click to see how it works?, which could be condensed organelle, single cells, tissues up to small intact organisms.
	NMT® can also help researchers to obtain information such as concentrations and motion directions of specific ions and molecules going in/out of the samples in optimized buffers. H⁺, Ca²⁺ , K⁺, Na⁺, Cl^-, NH₄⁺, Mg²⁺, Cd²⁺, NO₃^-, O₂ , H₂O₂ , Glucose, Glutamate and IAA can be measured individually or in combinations of two. What new information can NMT bring into my research? click to see more......?

Why Fluxes?

Case Study 01

Scientist & Research:

Dr.Park, University of Massachusetts
Optimization of Algae-based Wastewater Treatment Processes

Challenges:

A symbiotic granule composed of algae and bacteria is being developed to optimize the wastewater treatment processes.

NMT Solutions:

1) Because of its great temporal resolution (a few seconds) and super sensitivity (pico level), NMT can help the project by measuring the transient changes of oxygen releasing or absorbing under different light conditions, which is crucial to understand the relationships among the algae, the bacteria and the waste water;

2) Because NMT can tell people how fast and how much oxygen is releasing or absorbing by the granules, it can be plugged into calculations to quantatively optimize the wastewater treatment processes.

Case Study 02

Scientist & Research:

Dr.Chen, Beijing Forest University
Salt Stress/Resistance Research in Poplar

Challenges:
A symbiotic granule composed of algae and bacteria is being developed to optimize the wastewater treatment processes.n

Poplar is an excellent model to study salt stress/resistance, but there are few techniques suitable to study Na⁺, K⁺, Cl^- etc. which are essential players in this process, especially with living roots of Poplar. Chen's group has tried patch clamp for quite some time but no significant progress not only due to the Giga ohm seal challenges, but also because of the facts that when there are equivalent amount of transportations of both Na⁺ and K⁺ in the root of Poplar, the patch clamp will end up with '0' current if they are moving in opposite directions.

NMT Solutions:

Since NMT is using ion- molecule- selective micro sensor to detect the ions and/or molecules, Dr. Chen's group knew –

1) which ions and/or molecules they were studying before the experiments started;

2) both directions and magnitudes (how fast) of the ions/molecules they are measuring.measuring the transient changes of oxygen releasing or absorbing under different light conditions, which is crucial to understand the relationships among the algae, the bacteria and the waste water

Case Study 03

Scientist & Research:

Dr.Lin, Botany Research Institute of Sinica
Where is the Ca²⁺ coming from?

Challenges:

Calmodulin (CaM) is an important modulator of second messenger - Ca²⁺. But when CaM plays its role inside cells causing the falling of rising of internal Ca²⁺, there is always an critical issue if these Ca²⁺ being released from cellular Ca²⁺ stores or from being transported from external media.

NMT Solutions:

Because of its non-invasive nature, NMT was able to detect the influxes of Ca²⁺ and directly confirmed the confocal data showing an increase of internal Ca²⁺ concentrations.

How NMT Works?

theory2electrodes

NMT measures the concentration gradient of a specific molecule and/or ion by means of selective/specific micro-electrodes "vibrated" - repeatedly between points in user predefined fashion. The molecular/ionic fluxes are calculated based on the Fick’s law of diffusion:

Ficks

where J is the ion flux in x direction, dc/dx is its concentration gradient and D is its diffusion constant. The direction of the flux is derived from Fick’s law of diffusion that relates the concentration gradient to the diffusion coefficient.

Literatures

Literatures to Get Started

Jaffe LF and Nuccitelli R. An ultrasensitive vibrating probe for measuring steady extracellular currents. Journal of Cell Biology, 1974, 63: 614 - 628

Kühtreiber WM and Jaffe LF. Detection of extracellular calcium gradients with a calcium specific vibrating electrode. Journal of Cell Biology, 1990, 110: 1565 - 157

Kochian, L V, Shaff J E, Kuhtreiber W M, Jaffe L F & Lucas W J (1992) Use of an extracellular, ion-selective microelectrode system for the quantification of K⁺, H⁺, and Ca²⁺ fluxes in maize roots and maize suspension cells. Planta 188, 601-610.

Arif I. & Newman I.A. (1993) Proton efflux from oat coleoptile cells and exchange with wall calcium after IAA or fusicoccin treatment. Planta. 189, 377-383.

Smith, P.J.S. (1995). The non-invasive probes - tools for measuring transmembrane ion flux. Nature 378:645-646.

Shabala S.N., Newman I.A. & Morris J. (1997) Oscillations in H⁺ and Ca²⁺ ion fluxes around the elongation region of corn roots and effects of external pH. Plant Physiology 113, 111-118.

Xu Y, Sun T, Yin LP (2006). Application of non-invasive microsensing system to simultaneously measure both H⁺ and O₂ fluxes around the pollen tube. J Integr Plant Biol 48(7):823-831

Marshall Porterfield(2007), Measuring metabolism and biophysical flux in the tissue, cellular and sub-cellular domains: Recent developments in self-referencing amperometry for physiological sensing, Biosensors and Bioelectronics, Volume 22, Issue 7, 15 February 2007, Pages 1186-1196, ISSN 0956-5663

Hawkins BJ, et al.A comparison of ammonium, nitrate and proton net fluxes along seedling roots of Douglas-fir and lodgepole pine grown and measured with different inorganic nitrogen sources. Plant, Cell & Environment.2008, 31(3): 278–287.

Nemchinov LG, et al. Calcium efflux as a component of the hypersensitive tesponse of Nicotiana benthamiana to Pseudomonas syringae. Plant Cell and Physiology, 2008, 49(1): 40-46.

Ramos AC, et al. A pH signaling mechanism involved in the spatial distribution of calcium and anion fluxes in ectomycorrhizal roots. New Phytologist, 2009, 181(2): 448–462.

Sun J, et al. NaCl^-induced alternations of cellular and tissue ion fluxes in roots of salt-resistant and salt-sensitive poplar species. Plant Physiology, 2009, 149: 1141 - 1153.

Sun J, et al. H₂O₂ and cytosolic Ca²⁺ signals triggered by the PM H⁺-coupled transport system mediate K⁺/Na⁺ homeostasis in NaCl^-stressed Populus euphratica cells. Plant, Cell and Environment, 2010, 33: 943 - 958.

Jeworutzki E, et al. Early signaling through the Arabidopsis pattern recognition receptors FLS2 and EFR involves Ca²⁺-associated opening of plasma membrane anion channels.The Plant Journal.2010,62(3):367–378.

Alavian KN et al.Bcl xL regulates metabolic ef ciency of neurons through interaction with the mitochondrial F1F0 ATP synthase. Nature Cell Biology, 2011, 13(10): 1224-1233.

Michard E, et al. Glutamate receptor–like genes form Ca²⁺ channels in pollen tubes and are regulated by pistil D-serine. Science, 2011, 332(6028): 434-437.

Laohavisit A, et al. Arabidopsis annexin1 mediates the radical-activated plasma membrane Ca²⁺- and K⁺-permeable conductance in root cells. Plant Cell, 2012, 24(4): 1522-1533.

Li J, et al. Paxillus involutus strains MAJ and NAU mediate K⁺/Na⁺ homeostasis in ectomycorrhizal Populus × canescens under NaCl stress. Plant Physiology, May 2012 pp.112.195370