Dry thermostat is a constant temperature metal bath device controlled by microcomputer instead of traditional water bath device. It can be widely used in sample preservation and reaction, DNA amplification and pre denaturation of electrophoresis, serum coagulation and other fields.
In the actual use of the dry thermostat, customers often worry about the accuracy of the temperature, especially for the customers who have been using the dry thermostat for many years.
Usually, customers do not have complete testing instruments and perfect testing methods to evaluate the temperature accuracy of the instrument. Therefore, we generally recommend that the customer send the dry thermostat back to the manufacturer for re testing, and the manufacturer will evaluate the accuracy of the instrument temperature.
The necessary conditions for temperature calibration of dry thermostat are as follows:
1. Environmental requirements: We require temperature calibration at ambient temperature of 15℃ ~ 25℃.
2. Humidity requirements: The humidity should be lower than 85%.
3. One of the most important instruments for temperature calibration: the national second-class standard thermometer (0.1℃ scale), and it must be verified by the authoritative department. (For modules with large module holes) Ordinary thermometers or high-precision thermometers that have not been calibrated are not allowed.
4. The second most important instrument for temperature calibration: high precision thermistor and other sensors, and they must be verified by the authoritative department. (For modules with smaller module holes)
5. Test requirements: when the national second-class standard thermometer and high precision sensor are put into the module hole, they must contact the module very accurately. Generally, heat conducting oil (high temperature resistant oil, usually the ignition point must be higher than 200 ℃) and silicone grease are added into the hole.
6. Testing method: complete temperature calibration methods and instructions provided by the manufacturer
If users have the above prerequisites, they can calibrate the temperature by themselves.
One of the applications of all-optical wavelength microplate reader
Working principle of ultraviolet absorption method: The bases of nucleic acid molecules have the characteristics of absorbing ultraviolet ray, and the maximum absorption wavelength is 260nm. Under the wavelength of 260 nm, the optical density of 10D value is equivalent to the concentration of double stranded DNA of 50μg/ml, and it can be used to calculate the concentration of nucleic acid samples.
The ordinary microplate reader does not have this function, because it does not have 260nm, 280nm, 320nm light sources and related filters and all-optical wavelength microplate reader (200nm~850nm) has this function. However, when using the all-optical wavelength microplate reader, the material also has corresponding requirements:
Microplate: UV plate or quartz plate that can pass through ultraviolet light. Ordinary microplate cannot be used!
Detection wavelength: 260nm, 280nm and 320nm
Results: dsDNA concentration = (A260-A320)x50
(Take dsDAND as an example) dsDNA purity = (A260-A320)/ (A280-A320)
Note: our existing AMR-100 microplate reader does not contain this function.
Spectrophotometer is a kind of instrument for quantitative and qualitative analysis of substances by spectrophotometry. Spectrophotometry is the qualitative and quantitative analysis of the substance by measuring the absorbance of the measured substance at a specific wavelength or within a certain wavelength range.
When monochromatic light radiation passes through the measured substance solution, the amount absorbed by the substance is directly proportional to the concentration of the substance and the thickness (optical path length) of the liquid layer. And the relationship is as follows:
Where: A is the absorbance;
I. is the intensity of incident monochromatic light;
I is the intensity of transmitted monochromatic light;
T is the transmissivity of the substance;
K is the molar absorption coefficient;
L is the light path of the substance being analyzed, i.e. the side length of the cuvette.
C is the concentration of substance;
The selective absorption wavelength of light of the substance and the corresponding absorption coefficient of the substance are the physical constants of the substance. When the absorption coefficient of a pure substance under certain conditions is known, the sample for test can be prepared into a solution under the same conditions, and its absorption degree can be determined, then the content of the substance in the sample for test can be calculated from the above formula. In the visible light region, except some substances have absorption of light, many substances do not absorb light, but they can be determined by adding color reagent or after treatment under certain conditions, so it is also called colorimetric analysis. Because there are many factors that affect the shade of color, and the instrument with poor purity of monochromatic light is often used, the standard or reference substance should be used at the same time.
Ultramicro spectrophotometer has become a conventional instrument in modern molecular biology laboratory. It is often used to quantify nucleic acid, protein and bacterial growth concentration.
Heat sealing instrument, also known as plate sealer, sealing film machine; Plate generally refers to microplate. Microplate is widely used in high-throughput testing and cultivation in life science and chemical analysis industry. The common microplates include PCR plate, liquid chromatography, high-throughput detection matching deep-well multiwell plate, sample storage deep-well plate, ELISA plate and cell culture plate. The main purpose of the plate sealer is to prevent evaporation and leakage of various microplates in the detection reaction process by means of heating sealing various special heating sealing films. Another function of the plate sealer is to ensure the safe storage and transportation of samples in the microplate.
Plate sealer is generally divided into manual, semi-automatic and automatic. The automatic plate sealer is generally used in the drug screening matching workstation of large pharmaceutical factory, which has strong automation, but because of the complex structure and huge volume of the automatic equipment, the price is high; the price of manual plate sealer machine is low, and it is not suitable for long time sealing. The semi-automatic plate sealer has the advantages of both automatic plate sealer and manual plate sealer. The price of semi-automatic plate sealer is relatively low and is compact in structure, small in floor area and high in labor intensity. Its application scope is more extensive than that of automatic and manual plate sealer. It is mainly used to prevent evaporation of long-term freezing of blood samples and gene amplification experimental samples in blood center; sample storage of analysis instruments of CDC; prevention of evaporation of gene amplification experimental samples of public security forensic identification system and DNA workstation; sealing of microplate kit of kit manufacturer; It can also assist a large number of research-oriented research institutions, hospitals and school laboratories to carry out microplate related experiments.
At present, the most common semi-automatic plate sealer on the market is Sealbio-2 semi-automatic plate sealer; the most common automatic plate sealer is Plateloc microplate heat plate sealer produced by Agilent, which is mostly purchased by drug screening Department of large pharmaceutical factory. Sealbio-2 semi-automatic plate sealer can realize uniform and stable microplate sealing, which is an ideal choice for medium throughput laboratory. At the same time, the sealer also has the function of temperature and time adjustment, and different adapter can seal most of the PCR plates and microplates, so as to meet different needs.
Sealbio-2 semi-automatic plate sealer has excellent safety and energy saving:
The intelligent motor controls the entrance and exit of the cabin door. If hands or other objects obstruct the closing entrance and exit of the cabin door, the intelligent motor will reverse to protect users and instruments. It is with a special mechanism of smart design, the entrance and exit door can be separated from the sealer to clean and maintain the heating plate. Automatic standby function can save energy. When there is no action within 60 minutes, the sealer enters the standby mode, the temperature of the sealer will automatically drop to 60 ℃ to achieve the effect of energy saving. When there is no action within 120 minutes, the sealer will enter the "deep sleep" mode, turn off the display screen and cut off the power supply of the heater, leaving only a weak current supply to the core components of the control board, and then press any key, the sealer will resume its working state.
In almost every laboratory, the separation and purification work related to biomolecules is very important and necessary. However, it is quite difficult to purify multiple samples. It is not only necessary to select the appropriate purification technology, but also the workload is particularly large, which is difficult to meet the current rapid development of high-throughput sample extraction and purification needs. Magnetic bead automatic nucleic acid extraction and purification system uses magnetic bead technology, can be widely used in genomics, disease control and medical treatment, food safety, forensic identification and other fields.
Automatic nucleic acid extractor is very suitable for genomics research. The source of the samples can be extracted are microorganisms, animals, plants or viruses. The whole blood genomic DNA extraction kit, leukocyte layer whole blood genomic DNA extraction kit and animal tissue / cell genomic DNA extraction kit can quickly purify enough quantity and purity of DNA or RNA. High quality nucleic acid can meet the needs of various downstream applications (such as PCR / real-time PCR, gene chip, Southern blot, Northern blot).
The automatic nucleic acid extractor can be used to solve the rapid automatic disease monitoring system of influenza A virus subtype H1N1, hand-foot-mouth disease in children, measles virus and others, which can improve the response ability to major epidemic situations.
Molecular diagnosis of clinical samples
Automatic nucleic acid extractor can process clinical samples rapidly and with high throughput. The extracted nucleic acid can be used for subsequent molecular diagnosis, and it is also suitable for tissue samples of Formalin-Fixed and Parrffin-Embedded, FFPE.
Animal husbandry and veterinary
It can extract Avian influenza virus, Newcastledisease virus, Classical swine fever virus, CSFV, Bovine viral diarrhea virus, Coxiella burnetii and other virus efficiently and sensitively.
Application of Forensic Medicine
For forensic work, the efficiency and stability of nucleic acid extraction are very important. The automatic nucleic acid extractor is used together with the special magnetic bead reagent for nucleic acid extraction of forensic samples, can purify high-quality DNA from materials from different sources, including cigarette butts, hair roots, cartilage, nails, blood stains and so on.
FISH is a cytogenetic technique, which can be used to detect and locate nucleic acids. Fluorescent labeled nucleic acid probes hybridize only with highly similar nucleic acids, which can be used to locate genes on chromosome or to mark ribosomal RNA in different bacteria or Archaea in molecular ecology.
FISH technique is an important non - radioactive in situ hybridization(ISH). Its basic principle is as follows: If the target DNA on the detected chromosome or DNA fiber section is homologous and complementary with the nucleic acid probe used, the hybrid of the target DNA and the nucleic acid probe can be formed by denaturing-annealing-refolding. A nucleotide of the nucleic acid probe is labeled with a reporter molecule, such as biotin and digoxin. The immunochemical reaction between the reporter molecule and fluorescein labeled specific avidin can be used for qualitative, quantitative or relative localization analysis of the DNA to be detected by fluorescence detection system.
It can be used to check the number of chromosomes and the fine changes of parts. It is used to detect chromosomal abnormalities in newborn, such as chromosome 21-trisomy syndrome (Down), chromosome 18-trisomy syndrome (Edward), chromosome 13-trisomy syndrome (Patau), 45、XO (turner) and 47XXY (Klinfelter).
In the diagnosis of leukemia, the technology is very easy to find residual leukemia cells, especially suitable for leukemia patients after chemotherapy.
In terms of solid tumors, breast cancer is widely used in clinical diagnosis. Provide guidance for the administration of monoclonal antibody Herceptin; it is also suitable for ovarian cancer, endometrial cancer, salivary gland tumor, gastric cancer and other cancers.