Diagnostics Today
It is widely accepted that the early detection of cancer, and its deadly metastasis, is the most effective method for increasing the cure rate. Current cancer screening is unable to detect small tumors or breakaway tumor cells that lead to micrometastatic tumors. In fact, in 3% of the 13 million cancers diagnosed annually, even the origin site of the carcinoma remains undetected.

The inadequacy to detect diseases such as this at the molecular level and the need to better study fundamental biological pathways has led to the vast development of optical imaging probes.  Unfortunately, conventional optical imaging agents have significant technical limitations involving signal loss, high background interference and unacceptable toxicity.

Bikanta has developed nanodiamond-based technology that will redefine tomorrow's medical imaging, allowing researchers to answer questions and medics to detect diseases that they currently cannot.
nanodiamond properties & applications
Bikanta's fluorescent nanodiamonds are coated to robustly remain monodisperse and have nitrogen vacancy centers that give them uniquely valuable properties including the following.  Click on each property to learn more.
A nanodiamond is forever. At least, in terms of fluorescence signal, they are. Fluorescent nanodiamonds never photobleach or blink.

Bikanta's nanodiamonds are differentiated by coatings that stabilize the particles to withstand a range of conditions.  Rather than having the typical unreactive surface, they can be tightly bound to any targeting agent (e.g. aptamers, antibodies, polymers) and can therefore be tailored to detect specific diseases.

These nanodiamonds derive their fluorescence properties from negatively charged nitrogen-vacancy (NV¯) centers, a color center or defect in the diamond lattice consisting of a substitutional nitrogen and a neighboring lattice vacancy.  They are fluorescent sources with remarkable optical properties including:
quantum efficiency near unity
indefinite photo-stability (no photo-bleaching or blinking)
broad excitation spectra
exquisitely sensitive magnetic field modulation of fluorescence emission
long fluorescence lifetimes (~17ns)
near infrared fluorescence ideal for in vivo imaging.
Fluorescent Nanodiamonds
Quantum Dots
Organic Dyes
Resists photobleaching
Resists photoblinking
Multi-color excitation
Stokes shift
Two Photon Excitation
Quantum Efficiency
Long Fluorescence Lifetime
Optically Detected
Magnetic Resonance
Nitrogen-Vacancy Energy Levels
Laser excitation (480-640nm) of the NV center results in optical excitation of electrons into an excited state.  The electrons quickly decay to ground state by emitting a photon (638-800nm) or through a non-radiative process. Negatively charged centers (NV-) have a ground and excited triplet-state consisting of spin-projections ms=0 and ±1.  

Applying radio frequency (RF) radiation, such as microwave radiation, at a resonant frequency (2.87 GHz, zero-field splitting), causes the redistribution of electrons between the ground states. At zero magnetic field, the +1 and -1 states are degenerate (have the same energy). An external magnetic field lifts the spin degeneracy, splitting the two apart.Electrons excited from ground state 0 emit photons to revert with a high probability to the same ground state. Electrons excited from ground state +/-1 can become temporarily trapped in a dark “singlet” state before non-radiative decay with a high probability to ground state 0.

With a high probability, electrons excited from ground state 0 emit photons to revert to the same ground state. Electrons  excited from ground state +/-1 can become temporarily trapped in a dark “singlet” state before non-radiative decay to ground state 0. Therefore, fluorescence emissions can be controlled by or monitored to detect the presence of external RF radiation or magnetic field.
Imaging with Nanodiamonds
Bikanta is also designing novel imaging instrumentation that takes advantage of the nanodiamond properties.

A challenge in optical imaging is unmixing or separating fluorescent signal from background. Bikanta uses the magnetic sensitivity of fluorescent nanodiamonds to reduce background noise, more than 100-fold improvement. This translates to significantly more sensitive detection of low signal and deeper imaging into tissue, redefining the limits of optical imaging.
Nanodiamonds have uses in industries from manufacturing  to electronics to computing to medicine. Here we highlight the medical applications