Bridge12 manufacture high field EPR/ESR Instrumentation including accessories for solid state DNP NMR and Overhauser DNP.

TalaveraScience is the Senior Sales Consultancy for Client throughout Europe, the Middle East, India and Australasia.

Bridge12 was founded more than a decade ago by Dr Jagadishwar Sirigiri and Dr Thorsten Maly both former scientists from MIT with extensive experience in high-frequency terahertz (THz) sources, such as gyrotrons, microwave technology and magnetic resonance spectroscopy.

Bridge12 provides THz/microwave technology including: active and passive components such as gyrotrons and transmission lines for Dynamic Nuclear Polarization (DNP) enhanced NMR spectroscopy; turn-key high-frequency (>100 GHz) Electron Paramagnetic Resonance (EPR/ESR) systems; Overhauser DNP (ODNP) upgrades for any X-Band (9 GHz) EPR spectrometer.

Bridge12 products find their application in magnetic resonance (EPR/ESR, DNP and NMR) in both academic research and in industrial research and development. Bridge12 has supplied instruments and other products to research groups across the United States of America and elsewhere in Japan, South Korea, Germany and Israel.

Bridge12’s research and manufacturing facility is located near Boston in Framingham, Massachusetts, USA.

Please contact or for further details.

Bridge12 High-Field pulsed and cw EPR Spectrometers

Bridge12 PTR

Bridge12 build a series of cost effective modular continuous wave and pulsed high field EPR instruments using quasi-optical components. Modular means that the high field EPR instrument can be provided from a selection of configurations and upgraded simply to a higher specification at a later date. These high field EPR spectrometers are available as standard in the following confugurations:

These systems are fully supported, integrated and complete EPR spectrometers (no more do you need to worry about the departure of the group member who knows everything about the spectrometer). The cryogen-free magnets integrated with the system are manufactured by Cryogenic Ltd (for more information concerning these magnets, please view my Cryogenic Ltd web page and are fully sweepable magnets (from one maximum field polarity to the other) under the Bridge12 EPR spectrometer control. EPR spectrometers operating at more than one of these frequencies is also possible (or with a bespoke frequency, see below).

If you already have an appropriate magnet the Bridge12 high field EPR spectrometer 'electronics' can be provided to combine with your existing magnet and hardware. In addition, see below, the instrument can be added to existing hardware such as solid state DNP NMR systems to provide EPR spectrometer functionality in order to optimise the DNP experiment; please contact us to discuss.

If you have requirements utilising high field EPR outside of these specifications (such as different/bespoke frequency ranges), please contact us to discuss them and it will be our pleasure to offer cost effective solutions!

Bridge12 can also provide components for any HF EPR Instruments, Inc., 130 GHz: D-band cw/pulsed EPR systems you might have. Please contact us for details.

Please contact us if you would like to receive further information at

Bridge12 EPR for Solid State Dynamic Nuclear Polarisation NMR Systems

Bridge12 EPR system for Solid State DNP NMR

High field EPR Spectroscopy typically requires very expensive instrumentation including the spectrometer and a sweepable super conducting magnet system. Bridge12 have developed a cost effective high-field EPR spectrometer utilising state of the art microwave technology and quasi optics, pictured to the left, with its own integrated source to use an existing superconducting magnet to add: (a) the capability of EPR spectroscopy to existing gyrotron or EIK equipped solid state DNP NMR instruments, or; (b) EPR spectroscopy capability and low temperature DNP to existing NMR instruments.

Adding EPR Spectroscopy to your Solid State DNP NMR Instrument

Solid state DNP NMR is all about gaining massive sensitivity gains to allow experiments that would be impossible by solid state NMR, alone. So, why would the researcher forfeit sensitivity by not optimising the experimental conditions. This EPR spectrometer is connected to the waveguide between the gyrotron/EIK and the solid state DNP-NMR probe using a Bridge12 provided kit which does not make any changes to the wave guide. This then allows the acquisition of the EPR label spectrum so that the optimal polarising agent can be selected and the determination of optimal conditions.

Adding EPR Spectroscopy and Low Temperature DNP to your existing Solid State NMR Instrument

You would like to add low temperature DNP and EPR spectroscopy to your solid state NMR instrument. The cost effective solution from Bridge12 includes the high frequency EPR instrument and a microwave source for NMR frequencies up to 500 MHz 1H.

Please contact us if you would like to receive additional information at

Bridge12 X-band Overhauser Dynamic Nuclear Polarisation Capability

B12 ODNP Upgrade


Bridge12 provide a turn-key complete X-band Overhauser Dynamic Nuclear Polarisation (ODNP) capability which is compatible with homebuilt or commercial X-band EPR instruments. Bridge12 can provide individual X-band ODNP components or the complete solution for your EPR spectrometer.

The complete solution consists of:

  1. microwave source;
  2. single board NMR system;
  3. Open VnmrJ operating system;
  4. either a probe insert for ODNP (for an existing cavity);
  5. or a complete X-band ODNP resonator.

Technical Details

Requires an existing X-band cavity, examples of suitable cavities include: Bruker 4102ST, 4119HS, 4122SHQ, ER4123D or the Varian E231.

Requires > 5 lpm flow of dry, clean air.

Standard sample size: 2 mm.

Standard NMR Operating Frequency: 14.5 (±0.5) MHz.

Sample holder and probe mounts provided.

Please contact us for any other frequencies, nuclei, sample tube diameters, etc.

Bridge12 Microwave Power Source (MPS) for ODNP

Bridge12 Microwave Source for X-band ODNP

The MPS is a high power microwave source capable of generating >10 W at X-band.

It has a simple turn-key operation and full remote control for complete system integration.

Its status can be determined using the three panels available to view on its display screen. These are:

  1. the Main Screen (shown right top) displaying the output frequency and gain;
  2. the Tune Screen (shown right middle) displaying the tuning resonance when tuning the cavity;
  3. the Operate Screen (shown right bottom) showing the output status of the MPS during an experiment.

Single board NMR Instrument with Open VnmrJ for ODNP

Integrated, single-channel NMR spectrometer tuning from 13C to 1H for the Bridge12 Microwave Power Source.

The NMR spectrometer has Open VnmrJ for ODNP as the operating system shown below with an example of the X-band ODNP generated 1H NMR spectrum.

Bridge12 Open VNMRJ Operating System view

Bridge12 X-band ODNP Probe Upgrade

Bridge12 X-band ODNP probe upgrade

Compatible with TE102, TE011... EPR resonators and installable into standard X-band cavities such as the Varian E231 and the Bruker 4102ST, 4119HS, 4122SHQ, ER4123D, including all of the required parts.

The probe is carefully designed to minimise any changes in the Q-factor of the EPR cavity and to minimise sample heating even with high microwave powers.

Bridge12 Enhancement vs power simulation and experimental data for the X-band ODNP Probe Upgrade

The probe facilitates easy sample changing using the provided sample holders which are either a 2 mm OD, 1 mm ID 0.84 mm OD, 0.6 mm ID capillary tubes.

Bridge12 Complete X-band ODNP Resonator

A complete X-band ODNP Resonator with a high quality factor, easy sample handling and integrated RF coil with broadband tuning from 13C to 1H.

The image below left depicts the Bridge12 X-band ODNP Resonator and the graph below right shows simulation and results for the resonators performance.

Bridge12 X-band ODNP Resonator Bridge12 Enhancement vs power simulation and experimental data for the X-band ODNP Resonator

Bridge12 X-band ODNP Data Examples

Please see below for examples of high resolution 1H X-band ODNP NMR Spectroscopy using the Bridge12 X-band ODNP resonator.

Bridge12 example data from the X-band ODNP Capability Bridge12 example data from the X-band ODNP Capability

Bridge12 X-band ODNP Options

Bridge12 X-band ODNP Flow Resonator

Bridge12 X-band ODNP Flow Resonator for Halbach magnets

A X-band ODNP flow resonator for Halbach magnets consisting of:

  1. maximum sample diameter: 6 mm (without NMR coil), 4 mm (with NMR coil);
  2. homogeneous B1e field length >10 mm (<5% variation of B1e);
  3. microwave conversion factor >3 G/sqrt(W);
  4. single NMR channel available tunable from 13C to 1H.

Bridge12 Active Room Temperature Shims for EPR Magnets

Bridge12 data showing X-band ODNP 1H NMR lineshape improvement using RT shims for EPR magnets

The spectra above demonstrate the improvement in linewidth and resolution when utilising Bridge12's room temperature shims for EPR magnets. Below: left, shims for a Halbach magnet; right, for a Bruker ER073 EPR magnet.

Bridge12 room temperature shims for a Halbach Magnet Bridge12 room temperature shims for a Bruker ER073 electromagnet for EPR

Please contact us if you would like to receive additional information at

Bridge12 Microwave Accessories


Solid state DNP NMR currently requires a high power source of microwaves and at high frequencies as determined by the NMR magnetic field strength. This requires a source such as the gyrotron which satisfies both requirements.

Bridge12 manufactures gyrotrons design for solid state DNP NMR and can be used fir systems planning to run at cryogenic or cold temperatures. This is especially useful for converting and existing aolid state NMR system including solid state DNP NMR probes from Phoenix NMR; see

to make a cost effective and scientifically competitive instrument.

Bridge12 has an unique approach for converting existing magnets to gyrotrons for this use. Please contact us to discuss further...

GHz/THz Frequency Measuring Instruments

Do you know the exact frequency emitted by your GHz/THz source?

Would you like to track the frequency during your experiment?

Bridge12 have the perfect instrument to do this and is ideal for troubleshooting solid state DNP NMR experiments; the Bridge12 Frequency Measurement System (FMS).

The Bridge12 FMS is a well documented and supported turn-key frequency measuring system consisting of a heterodyne broadband receiver capable of measuring frequencies from 26 GHz to 500 GHz (depending on the input mixer).

The Bridge12 FMS is controlled through a simple software interface with two modes: measure and; track and can be installed on a gyrotron control system, the EPR spectrometer computer or a Windows-based computer.

Microwave Components

Bridge12 can provide a whole range of microwave components for you.

These include waveguides for EPR and DNP applications, microwave and terahertz sources (see picture below) and Quasi-Optical Components (the Bridge12 high frequency EPR instruments are modular and can be built up into an instrument or built in to an existing instrument).

If there is something you need, please contact us...

Bridge12 microwave source
Quasi Optics Image