Bridge12 manufacture high field EPR/ESR Instrumentation including EPR Spectrometers, microwave sources and accessories for EPR, 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 and each with extensive experience in high-frequency terahertz (THz) sources, such as gyrotrons, microwave technology and magnetic resonance spectroscopy.

Bridge12 develops and 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) instruments; compact Q-band pulsed EPR instruments; EPR resonators, X-band Overhauser DNP (ODNP) systems and upgrades for any X-Band EPR spectrometer. Bridge12 also provides individual microwave components for use in EPR and DNP for use in the homebuilder scientist's projects.

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

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

Please scroll down to browse further and find more information!

Please contact info@talaverascience.com or pjonsen@bridge12.com for further details.

Bridge12 High-Field 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 about these dry magnets, please view my Cryogenic Ltd web page https://talaverascience.com/tsCryogenic.html) 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.

The Bridge12 high frequency EPR spectrometers use the SpecMan4EPR interface (software developed by Professor Boris Epel) with its many advantages over other offerings in the market place.

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 140 GHz: D-band cw/pulsed EPR instruments manufactured by HF EPR Instruments, Inc., you might have. Please contact us for details.

Please contact us if you would like to receive further information at info@talaverascience.com.

Bridge12 Compact Q-band EPR Spectrometers

One EPR application that has become very popular in recent years is that of Pulsed Dipolar Spectroscopy to measure distances between EPR labels to determine molecular structure using techniques such as PELDOR/DEER (Pulse Electron-Electron Double Resonance/Double Electron-Electron Resonance), RIDME (Relaxation Induced Dipolar Modulation) and DQC (Double Quantum Coherence) EPR. These techniques have found application at Q-band. Bridge12 has identified that these techniques could be much more widespread if an EPR spectrometer was designed and built with these as core design requirements. Therefore, the Bridge12 Compact Q-band EPR Spectrometer concept was developed and built.

The Bridge12 Compact Q-band EPR Spectrometer is based around:

  1. the Bridge12 microwave generation with an AWG and digital demodulation (for cleaner signal generation and detection);
  2. a very compact Liquid Helium Free superconducting magnet equipped with an integrated Variable Temperature Insert (iVTI);
  3. high performance resonators with unparalleled performance (the resonators are discussed later in this page);
  4. a choice of 40 W or 100 W solid state amplifiers.
Cryogenic Ltd compact Q-band EPR magnet

The Bridge12 Compact Q-band EPR spectrometer uses the SpecMan4EPR interface (software developed by Professor Boris Epel). There are many advantages of this interface with one being the ease-of-use in acquiring experiments based on echo-train detection such as ED EPR (Echo Detected EPR), Davies and Mims Electron-Nuclear Double Resonance (ENDOR), DEER and ED NMR when combined with a CPMG (Carr-Purcell-Meiboom-Gill) sequence. The Bridge12 Q-band EPR instrument can record whole echo traces rather than just the integral, giving users the freedom to select the integration gate after the measurement, thereby finding the optimal trade-off between resolution and sensitivity! And, if the pulses are non-selective the echo traces can be Fourier transformed to yield information in the frequency domain. Multidimensional EPR experiments (such as Hyperfine sublevel correlation (HYSCORE) spectroscopy) are easily facilitated in SpecMan4EPR.

The cryogen free magnet is manufactured by Cryogenic Ltd (see the image to the right and https//:talaverascience.com/tsCryogenic.html) and can be fully swept across its field range and is equipped with an iVTI with a temperature range of 2 to 300 K using one cold head based on Cryogenic Ltd’s patented independent thermal circuit technology. This is connected to the helium compressor via two 20 m helium hoses and is compatible with Flexline-style resonators such as the Bridge12 resonators and those that fit into the Cryogenic Ltd cryogen free cryostat for EPR or the Oxford Instruments CF935 cryostat.

The Bridge12 Compact Q-band EPR spectrometer is available for demonstrations! These are in person at the Bridge12 facility in Natick, MA, USA or by video conference call! We look forward to speaking with you! Contact Bridge12 or info@talaverascience.com.

Please contact us if you would like to receive further information at info@talaverascience.com.

Bridge12 X and Q-band Resonators

Bridge12 have designed and built loop gap resonators for high performance pulsed applications at X-band and Q-band in EPR. For each resonator, the sample is mounted on a sample stick for easy inserting of the sample at any temperature within the resonators' operating temperature range.

Bridge12 X-band Loop Gap Resonators

Bridge12 Q-band Loop Gap ResonatorThe Bridge12 X-band loop gap resonator, denoted B12XLP, is a versatile resonator optimised for pulsed X-band EPR spectroscopy.

The B12XLP can include a remotely tuned radio frequency coil for ENDOR or DNP applications either tuned for a single frequency for maximum sensitivity (for DNP) or with broadband tuning for frequency sweeping the radio frequency.

The B12XLP can be operated over a temperature range of 2 to 300 K and is compatible with the Cryogenic Ltd CF VTC for EPR (see the Cryogenic Ltd webpage ) from 2 to 300 K and the Oxford Instruments CF935 flow cryostat (please inquire concerning other compatible cryostats). Importantly, especially when using cryogen free cryostats, each B12XLP resonator is leak tested and vacuum tight! For accurate sample temperature measurement, the temperature sensor is mounted very close to the cavity.

The B12XLP resonator is connected to the spectrometer using a standard SMA connection.

The B12XLP accepts sample tubes of <4 mm.

Browse the Bridge12 B12TXLP webpages for more details: https://www.bridge12.com/products/x-band-pulsed-epr-endor-resonator/

Bridge12 Q-band Loop Gap Resonators

The Bridge12 Q-band Loop Gap Resonators (LGR), denoted B12QLP, are designed for pulsed EPR experiments such as PELDOR/DEER and DQC where a high bandwidth is required without compromising on the microwave conversion factor and providing excellent microwave field homogeneity across the sample.

Bridge12 B12QLP ResonatorThe B12TQLP is the first commercially available LGR resonator for pulsed EPR spectroscopy and have a very large bandwidth, sufficient to perform PELDOR/DEER on previously difficult spin-label combinations and with a high microwave conversion factor guaranteeing high sensitivity.

There is a choice of two Bridge12 B12TQLP resonators available with sample tube OD sizes of 1.6 and 2.5 mm; the former for use with limited sample and the highest B1 fields and the later when sample is not limited and greater sensitivity is required.

For high accuracy, the B12TQLP resonators have a temperature sensor mounted next to the sample where the experiments’ temperature is regulated rather than the cryostat temperature sensor. The B12TQLP resonator is compatible with the Cryogenic Ltd CF VTC for EPR (see the Cryogenic Ltd webpage ) from 2 to 300 K and the Oxford Instruments CF935 flow cryostat (please inquire concerning other compatible cryostats). Importantly, especially when using cryogen free cryostats, each B12TQLP resonator is leak tested and vacuum tight!

Some EPR experiments require light irradiation of the sample and this is achievable with the B12TQLP resonators as an option using the optical window available on some cryostats or via fibre optic or both!

Bridge12 B12TQLP Resonator DEER trace






Q-band DEER and DQC EPR experiments of MS57-2/o-Terphenyl at 65 K using the Bridge12 B12TQLP resonator (data courtesy of Professor Song-I Han, UCSB). The Bridge12 B12TQLP resonator is ideally suited for DEER and DQC experiments. At Q-Band, the TEMPO spectrum has a width of ~250 MHz, so, with >400 MHz bandwidth and a large microwave conversion factor the entire spectrum can be excited for DQC spectroscopy as demonstrated to the image to the left.









Bridge12 B12TQLP Resonator distance plot





The Bridge12 B12TQLP resonator was developed for dipolar pulsed EPR experiments such as DEER/PELDOR, DQC, etc. Its large excitation bandwidth and microwave conversion factor guarantees high sensitivity and results in short acquisition times. The image to the right is of the analysed DEER experiment obtain on the Bridge12 QLP resonator on a sample of MS57-2/o-Terphenyl at 65 K using the B12TQLP (data courtesy of Prof. Song-I Han, UCSB, the data was analysed using the SVD method, Madhur Srivastava, Cornell University).







Browse the Bridge12 B12TQLP webpages for more details: https://www.bridge12.com/products/q-band-pulsed-epr-resonator/

Please contact us if you would like to receive further information at info@talaverascience.com.

Bridge12 X and Q-band Solid State Amplifiers

Pulsed EPR experiments usually require high microwave power which is realised by using a travelling wave tube (TWT) amplifier. Bridge12 brings to the market a range of solid state amplifiers for both X-band and Q-band. These are:

These amplifiers are an ideal back up for existing TWT amplifiers or, indeed, their replacement. The Q-band solid state amplifiers are those provided for the Compact Q-band Pulsed EPR spectrometer described above and if used with the Bridge12 Q-band Loop Gap resonator the 40 W and 100 W amplifiers are more than enough: 150 and 300 W is not required for their useful operation.

The amplifier pictured 'behind' this section is of the 100 W Q-band solid state amplifier (Model B12T AMP-Q100).

Please contact us if you would like to receive further information at info@talaverascience.com.

Bridge12 EPR for Solid State Dynamic Nuclear Polarisation (DNP) NMR Systems

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 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 600 MHz 1H.

Please contact us if you would like to receive additional information at info@talaverascience.com.

Bridge12 X-band Overhauser Dynamic Nuclear Polarisation (ODNP)

Description

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

Bridge12 X-band ODNP ResonatorA complete X-band ODNP Resonator with a high quality factor, easy sample handling and integrated radio frequency coil with broadband tuning from 13C to 1H (depicted in the image directly to the left).



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 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 info@talaverascience.com.

Bridge12 Microwave Accessories

Gyrotrons

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 for systems planning to run at cryogenic or cold temperatures. This is especially useful for converting and existing solid state NMR system including solid state DNP NMR probes from PhoenixNMR; see

https://talaverascience.com/tsPhoenix.html.

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 10 W X-band microwave source