Visualizing biological structures and cellular processes in their native state is a major goal of many scientific laboratories. In the past 20 years, the technique of preserving samples by vitrification has greatly expanded, specifically for use in cryogenic electron microscopy (cryo-EM). Here, we report on improvements in the design and use of a portable manual cryogenic plunge freezer that is intended for use in laboratories that are not equipped for the cryopreservation of samples.
The construction of the instrument is economical, can be produced by a local machine shop without specialized equipment, and lowers the entry barriers for newcomers with a reliable alternative to costly commercial equipment. The improved design allows for successful freezing of isolated proteins for single particle analysis https://biodas.org/ as well as bacterial cells for cryo-electron tomography. With this instrument, groups will be able to prepare vitreous samples whenever and wherever necessary, which can then be imaged at local or national cryo-EM facilities.
Successful short-term cryopreservation of volume-reduced cord blood units in a cryogenic mechanical freezer: effects on cell recovery, viability, and clonogenic potential
BACKGROUND
Cord blood (CB) units are stored from weeks to years in liquid- or vapor-phase nitrogen until they are used for transplantation. We examined the effects of cryostorage in a mechanical freezer at -150°C on critical quality control variables of CB collections to investigate the possible use of mechanical freezers at -150°C as an alternative to storage in liquid- (or vapor-) phase nitrogen.
METHODS
A total of 105 CB units were thawed and washed at different time intervals (6, 12, 24, and 36 months). For every thawed CB unit, samples were removed and cell enumeration (total nucleated cells [TNCs], mononuclear cells [MNCs], CD34+, CD133+) was performed. In addition, viability was obtained with the use of flow cytometry, and recoveries were calculated. Also, total absolute colony-forming unit counts were performed and progenitor cell recoveries were studied by clonogenic assays.
RESULTS
Significant differences (p < 0.05) were observed in certain variables (TNCs, MNC numbers, viability) when they were examined in relation with time intervals, while others (CD34+, CD133+) were relatively insensitive (p = NS) to the duration of time interval the CB units were kept in cryostorage condition.
CONCLUSIONS
The data presented suggest that cryopreservation of CB units in a mechanical freezer at -150°C may represent an alternative cryostorage condition for CB cryopreservation.
Realignment-free cryogenic macroscopic optical cavity coupled to an optical fiber
We present a cryogenic setup where an optical Fabry-Perot resonator is coupled to a single-mode optical fiber with coupling efficiency above 90% at mK temperatures without realignment during cooling down. The setup is prealigned at room temperature to compensate for the thermal contraction and change of the refractive index of the optical components during cooling down.
The high coupling efficiency is achieved by keeping the setup rotation-symmetric around the optical axis. The majority of the setup components are made of Invar (FeNi36), which minimizes the thermal contraction. High coupling efficiency is essential in quantum optomechanical experiments.
Extraordinary approach to further boost plasmonic NIR-SERS by cryogenic temperature-suppressed non-radiative recombination
We report an effective strategy to promote the near-infrared surface-enhanced Raman scattering spectroscopy (NIR-SERS) activity by boosting the photon-induced charge transfer (PICT) efficiency at cryogenic temperature. Based on as-prepared Au/Ag nano-urchins (NUs) with abundant surface defects, the extremely low temperature (77 K) can significantly weaken the metallic lattice vibration and reduce the recombination of thermal phonons and photoexcited electrons, then accelerate the migration of energetic electrons.
It enables the NIR-SERS detection limit of dye molecules to be achieved at 10-17 M, which is nearly three orders of magnitude better than that at room temperature. The present work provides a new, to the best of our knowledge, approach for ultra-trace NIR-SERS bioanalysis.
Ultra-stretchable and fast self-healing ionic hydrogel in cryogenic environments for artificial nerve fiber
Self-healing materials behave irreplaceable advantages in biomimetic intelligent robots (BIR) for avoiding or reducing safety hazards and economic losses from accidental damage during service. However, the self-healing ability is unreservedly lost and even becomes rigid, fragile in the cryogenic environment where BIR is precisely needed. Here, we report a versatile ionic hydrogel with fast self-healing ability, ultra-stretchability, and stable conductivity, even at -80℃.
The hydrogel is systematically optimized to improve hydrogen-bonded network nanostructure, coordinated achieving a quick self-healing ability within 10 min, large deformation tolerance of over 7000%, superior conductivity of 11.76 S·cm-1 and anti-freezing ability, which is difficult to obtain simultaneously. Such hydrogel provides new opportunities for artificial electronic devices in harsh environments. As a prospective application, we fabricate an artificial nerve fiber by mimicking the structure and functions of the myelinated axon, exhibiting the property of fast and potential-gated signal transmission.
This artificial nerve fiber is integrated into a robot for demonstrating a real-time high fidelity and high throughput information interaction under big deformation and cryogenic temperature. The hydrogel and bionic device will bring pioneering functions for robots and open a broad application scenario in extreme conditions. This article is protected by copyright. All rights reserved.
Cryogenic temperature sensing based on the temperature dependence of color centers in optical fibers
A cryogenic temperature sensor based on the temperature dependence of stable color centers in a commercial single-mode optical fiber is proposed. The radiation induced attenuation spectra at different temperatures are measured and decomposed by Ge-NBOHC and Ge(X) color centers. The configurational coordinate model is used to explain the temperature properties of the color centers.
A series of experiments are conducted to evaluate its performance in the temperature range from 10°C to -196°C, and the results suggest that the temperature sensitivity is ∼0.17 dB/km/°C with a resolution of 0.034°C, and the nonlinearity and repeatability error are ±3.8% and 1.4%, respectively.
Revealing the Intrinsic Atomic Structure and Chemistry of Amorphous LiO 2-Containing Products in Li-O 2 Batteries Using Cryogenic Electron Microscopy
Aprotic lithium-oxygen batteries (LOBs) are promising energy storage systems characterized by ultrahigh theoretical energy density. Extensive research has been devoted to this battery technology, yet the detailed operational mechanisms involved, particularly unambiguous identification of various discharge products and their specific distributions, are still unknown or are subjects of controversy. This is partly because of the intrinsic complexity of the battery chemistry but also because of the lack of atomic-level insight into the oxygen electrodes acquired via reliable techniques. In the current study, it is demonstrated that electron beam irradiation could induce crystallization of amorphous discharge products. Cryogenic conditions and a low beam dosage have to be used for reliable transmission electron microscopy (TEM) characterization.
High-resolution cryo-TEM and electron energy loss spectroscopy (EELS) analysis of toroidal discharge particles unambiguously identified the discharge products as a dominating amorphous LiO2 phase with only a small amount of nanocrystalline Li2O2 islands dispersed in it. In addition, uniform mixing of carbon-containing byproducts is identified in the discharge particles with cryo-EELS, which leads to a slightly higher charging potential. The discharge products can be reversibly cycled, with no visible residue after full recharge. We believe that the amorphous superoxide dominating discharge particles can lead researchers to reconsider the chemistry of LOBs and pay special attention to exclude beam-induced artifacts in traditional TEM characterizations.
Tissue and Cell Extraction and Purification |
|||
| EP10011 | Neuromics | 100 Tests | 636 EUR |
p5 Ligand for Dnak and and DnaJ |
|||
| 5-01680 | CHI Scientific | 4 x 5mg | Ask for price |
Linsmaier and Skoog, With macro- and micronutrients |
|||
| CP021-010 | GenDepot | 10X1L | 101 EUR |
Linsmaier and Skoog, With macro- and micronutrients |
|||
| CP021-500 | GenDepot | 50L | 126 EUR |
Murashige and Skoog, With Vitamins and Glycine |
|||
| CP031-010 | GenDepot | 10X1L | 99 EUR |
Murashige and Skoog, With Vitamins and Glycine |
|||
| CP031-500 | GenDepot | 50L | 126 EUR |
p5 Ligand for Dnak and and DnaJ Peptide |
|||
| 20-abx266082 | Abbexa |
|
|
Murashige and Skoog |
|||
| CP023-010 | GenDepot | 10X1L | 99 EUR |
Murashige and Skoog |
|||
| CP023-500 | GenDepot | 50L | 126 EUR |
Nitsch and Nitsch |
|||
| CP036-010 | GenDepot | 10X1L | 101 EUR |
Nitsch and Nitsch |
|||
| CP036-500 | GenDepot | 50L | 126 EUR |
Shenk and Hildebrandt |
|||
| CP038-010 | GenDepot | 10X1L | 101 EUR |
Shenk and Hildebrandt |
|||
| CP038-500 | GenDepot | 50L | 126 EUR |
Recombinant Human AND |
|||
| P0015 | FN Test | 100ug | 522.36 EUR |
Mouse Ariway PrimaCell3: Normal Bronchial and and Tracheal Fibroblasts |
|||
| 2-82003 | CHI Scientific | 1 Kit | Ask for price |
Rat Ariway PrimaCell3: Normal Bronchial and and Tracheal Fibroblasts |
|||
| 2-82503 | CHI Scientific | 1 Kit | Ask for price |
Human Airway PrimaCell4: Normal Bronchial and and Tracheal Fibroblasts |
|||
| 2-96004 | CHI Scientific | 1 Kit | Ask for price |
Murashige and Skoog, 1/2 Micronutrients and 1/2 Iron |
|||
| CP024-010 | GenDepot | 10X1L | 99 EUR |
Murashige and Skoog, 1/2 Micronutrients and 1/2 Iron |
|||
| CP024-500 | GenDepot | 50L | 126 EUR |
Murashige and Skoog, With Vitamins, Glycine, and 30g/L Sucrose |
|||
| CP032-010 | GenDepot | 10X1L | 101 EUR |
Murashige and Skoog, With Vitamins, Glycine, and 30g/L Sucrose |
|||
| CP032-500 | GenDepot | 50L | 126 EUR |
RNase and DNAase Away |
|||
| DB0339 | Bio Basic | 200ml | 72.62 EUR |
Blunting and Ligation Kit |
|||
| BS243 | Bio Basic | 10Preps | 102.2 EUR |
cool-pack and platfom |
|||
| EHS1300-COOL | Consort | ea | 124 EUR |
cool-pack and platfom |
|||
| EHS1400-COOL | Consort | ea | 124 EUR |
cool-pack and platfom |
|||
| EHS1500-COOL | Consort | ea | 149 EUR |