|Date: February 16, 1998|| Thermal Cyclers Chart|
DNA Ligation Chart
Twelve companies offer inexpensive cyclers, with prices ranging from just under $2000 to around $5000. These models include personal cyclers or minicyclers, multiblock thermal cyclers, and thermal cyclers with user-interchangeable blocks. Taking into account width, length, and height, thermal cyclers offering smaller footprints include the MJ Research MiniCycler, the Biometra Personal Cycler, the Bio-Rad GeneCycler, and the Techne Progene. It is likely there is an inexpensive thermal cycler that can handle just about any sample format you might have, be it 0.2 to 0.5 ml microfuge tubes, microplates, capillary tubes, or slides for in situ cycling. Don't be under the impression that by saving some money you will be forced to make sacrifices with regard to performance and features, either. These machines can stand up on their own blocks.
Program options on these affordable units vary, but most machines offer storage of 90 to 100 programs, and a few offer program protection. Several heating mechanisms are represented in this subset, with about half of the units Peltier- based. Other methods include electrical resistance, cartridge heaters, and heating by halogen bulb. Ramp rates among these thermal cyclers generally fall between 1° and 3°C per second. Two thermal cyclers set themselves apart from the rest in this category, however. The RapidCycler from Idaho Technology can ramp at up to 10-C per second, while the RoboCycler from Stratagene eliminates block ramping altogether by robotically transferring samples among blocks preheated to desired reaction temperatures. If ramp rates are of interest to your laboratory, find out if the manufacturer is reporting the ramp rate of the sample block or that of the reaction vessel.
Two important considerations when studying price tags are warranty options and certain PCR license rights. Manufacturer warranties fall between one and six years, and only four of the machines listed (the Hybaid Omn-E and PCR Sprint, the PE Applied Biosystems GeneAmp PCR System 2400, and Stratagene's RoboCyclers) include an "authorization" to perform PCR in certain applications.
Here's a look at what manufacturers have to offer.
Biometra Personal Cycler
Biometra UNO Thermoblock
The Personal Cycler from Biometra earned high marks in a 1995 test drive of thermal cyclers priced around $3000 (T. F. Unger, BioConsumer Review, Summer 1995, pp. 17-22). Its easy-to-use menu-driven display, interchangeable block feature, and performance combined to give it a share of the BioConsumer Review Award for Excellence. The Personal Cycler is a Peltier-based cycler that features interchangeable heating blocks, an optional heated lid, an in-tube sensor, and Hot Start and Touch Down functions. The Personal Cycler can store up to 100 programmable profiles in a nonvolatile memory and can accept 0.2 or 0.5 ml tubes.
Also from Biometra is the UNO Thermoblock, which sports three interchangeable blocks for several tube sizes, microtiter plates, or in situ applications. This Peltier-driven unit also features an optional heated lid, Hot Start and Touch Down functions, and a storage capacity of 30 programs. Both the Personal Cycler and UNO Thermoblock have RS232 and Centronics interfacing abilities.
The Bio-Rad Gene-Cycler swoops in as one of the most affordable thermal cyclers of 1998 with a list price of $2500. With its small footprint, heated lid, and program storage abilities (up to 100 comprised of cycles and steps within cycles), the GeneCycler isn't about to be intimidated. This unit also features program linking. Using resistive heating and a fan for cooling, this cycler can ramp up to 1.5°C/sec and down at 0.8°C/ sec. The GeneCycler also utilizes software algorithms to compensate for temperature differences between the block and the sample, so the temperature displayed corresponds to the temperature inside the reaction tube. The GeneCycler accepts 24 0.2 ml tubes.
Ericomp Single Block System
PowerBlock I System PowerBlock II System
SingleBlock System DeltaCycler I System
The PowerBlock I and II Systems from Ericomp are Peltier-based personal cyclers, with the Power-Block II having two temperature blocks. For laboratories with increased thermal cycling needs, the PowerBlock I is upgradeable to the PowerBlock II. Both units accept 0.2 or 0.5 ml tubes, and the PowerBlock II lets users run two independent cycling programs simultaneously in its dual blocks. Both units feature an in-sample probe, optional heated lid, storage of up to 99 programs, program linkage, two programming modes, and three-year warranties.
Ericomp's workhorse, the SingleBlock System, is a water-cooled temperature cycler that can handle 0.2 and 0.5 ml tubes, a microtiter plate, or in situ slides. Similar to the PowerBlock Systems, the SingleBlock System has an in- sample probe, optional heated lid, storage of 99 programs, and program linkage. These units also feature five-year warranties.
The DeltaCycler I, another Peltier-based cycler, utilizes a unique, proprietary Thermoelectric Temperature Controlled System for highly reliable temperature control. This high throughput unit can accept a 96-well microplate, 96 0.2 ml tubes, or 60 0.5 ml tubes and offers an optional in situ adapter. A three-year warranty is standard for the DeltaCycler I.
Hybaid's Omn-E checks in at only 19 cm wide, making it ideal for any benchtop. This personal cycler is available with a choice of block formats compatible with 0.5, 0.3, and 0.2 ml tubes or a 96-well microplate. The Omn-E also offers three methods of temperature control: tube control, simulated tube control, and block control. The Omn-E features an optional heated lid, a standard heat shield, and storage of up to 36 programs. Ringing up at a base price of $1995, the Omn-E is the least expensive cycler available today.
The most recent addition to Hybaid's range of cyclers, the new PCR Sprint, was launched in January 1998. This compact personal cycler offers an auto-adjust heated lid as well as interchangeability between 0.2 ml and 0.5 ml formats. The PCR Sprint incorporates state-of-the-art Peltier technology, providing excellent block performance with ramping rates up to 3°C per second and achieving well-to- well uniformity of better than ±0.5°C at 15 seconds. Hybaid's unique active tube control method, as well as simulated tube and block control methods is available for this unit. Hybaid thermal cyclers are licensed for the patented PCR process.
Idaho Technology RapidCycler
Idaho Technology's RapidCycler is just that-rapid. Featuring a halogen heating element and ramp times of 10-C/sec, this machine can handle 30 cycles in less than 10 minutes. The RapidCycler accepts 5 to 50 æl glass microcapillary tubes or 10 to 200 ml thin-walled micro-centrifuge tubes. Capillary tubes offer a high surface area to volume ratio, making them ideally suited for fast temperature cycling. The tubes are held at microtiter spacing for simultaneous sample pickup, cycling, and delivery. An optional buffer system allows direct loading of the sample onto gels without further manipulation. In terms of programming, the Rapid Cycler can store up to 99 cycle programs and features program linking abilities.
Lab-Line Programmable Thermal Block
Programmable Thermal Block
The Programmable Thermal Block from Lab-Line is a Peltier-based (heating and cooling) cycler available with a variety of user-interchangeable block formats, accepting 0.2 and 0.5 ml tubes, a microtiter plate, and four in situ slides. A unique lock-down heated lid with built-in power supply, a large, waterproof membrane keypad with a 4-line by 20-character Super Twist LCD, and small footprint highlight the features of this temperature cycler. The Programmable Thermal Block also has a user-friendly "menu-driven" program that does not require an operation manual for complex programming. This module can also store up to 100 programs and includes data-logging software that can display or store data and graphs. Program linking is also available with the Programmable Thermal Block.
|MJ Research MiniCycler|
If you've been to a biotechnology trade show anytime in the last few years, chances are you've seen the Desert Storm camouflage version of MJ Research's PTC-100. This Peltier cycler features an optional heated lid, optional in-sample probe, and storage for a whopping 360 programs. Capable of cycling 0.2 and 0.5 ml tubes, 96- or 192-well microplates, or 16 in situ slides, the PTC-100 can also accept MJ's speedy silver-gold block, which can ramp up at 2.5°C/sec.
The PTC-150 MiniCycler from MJ Research incorporates a sophisticated Peltier/Joule heat pump for speedy ramping (averaging 1.8°C/sec in the 50- to 100-C range) and accurate cycling. Sample formats include 16 0.5 ml tubes, 25 0.2 ml tubes, and 36 positive-displacement pipette tips, helpful in field usage. The Hot Bonnet¦ heated lid keeps reaction vessels tightly sealed for oil-free cycling. The MiniCycler's memory can store up to 80 programs, and data are displayed on the 32-character LCD. This device shared BioConsumer Review's Award for Excellence in a 1995 user test drive.
PE Applied Biosystems GeneAmpTM PCR System 240
GeneAmpTM PCR System 2400
A unique feature of the GeneAmpTM PCR System 2400 is the intuitive graphical user interface which displays real-time temperature and time data. Apart from the 7 x 40 character LCD, the user interface consists of a full numeric keypad and soft keys. The GeneAmp PCR System 2400 has a 24-well aluminum sample block and heated cover for oil-free cycling and is calibrated to standards traceable to the NIST (National Institutes for Standards and Technology, U.S.). The 2400's internal memory can store 68 complete PCR methods, and a program protection feature prevents programs from being inadvertently erased. Lastly, the 2400 has a PCMCIA slot for easy future upgrades.
RoboCyclerTM 40 and 96
Stratagene's Robocyclers robotically transfer samples between temperature blocks preset to desired reaction temperatures. This rapid transition between blocks eliminates the need to ramp to block temperature. The blocks of the RoboCyclers are also isothermic, optimizing well-to-well uniformity between samples. As an option, RoboCyclers can be fitted with an independent Hot Top assembly for oil- free thermal cycling; the Hot Top can also be ordered by those currently using RoboCyclers. The RoboCycler can store up to 99 programs with four windows per program, and up to 10 programs can be linked. The four temperature blocks can be independently programmed for time and temperature. The RoboCycler 40 can accept 40 0.6 ml thin-wall tubes or 0.5 ml tubes, while the RoboCycler 96 can handle a 96-well V-bottom microplate, 96 0.2 ml tubes, or 12 eight-tube strips. Both models have an industry leading temperature uniformity control of ±0.1°C.
St. John Associates BioOven III
One of the unique cyclers in this profile, the BioOven III from St. John Associates features very high sample capacity and can accept numerous formats, including microfuge tubes, microtiter plates, in situ slides, and capillary tubes. Using a fan to circulate electrically heated air and a rotating sample tray, the BioOven III boasts superior temperature uniformity within the unit. The menu-driven controller allows simple programming and sophisticated features, and the nonvolatile memory can store up to 99 profiles, as well up to 99 programs-a program being a series of up to 20 profiles. The four-line LCD lists sample and target temperature, name of program or profile being run, total cycle count in the program, current cycle count, and elapsed time.
The Progene is a small, Peltier-driven speedster, ramping up at an average of 2.8°C/sec and back down at 2.2°C/sec with a full load of 25 0.2 ml microfuge tubes. Featuring a small footprint, two-line LCD, a heated lid, and a high tolerance PRT sensor, the Progene is available in two formats: one for 25 0.2 ml microfuge tubes or 5 x 5 multiwell plates and one for 20 0.5 ml microfuge tubes. The Progene's blocks are also user-interchangeable. The Progene's memory can store 50 programs with up to nine segments per program. Additionally, the Progene has a feature allowing incremental/decremental segment hold times as well as temperatures.
Techne's Genius is a versatile, high throughput thermal cycler, accepting 0.2 and 0.5 ml microfuge tubes; 96-, 192-, and 384-well microplates; a 0.2 ml Robbins plate; and a flat plate for in situ cycling. Blocks can be changed in a matter of seconds without any tools. This Peltier powerhouse can ramp up at 2.8°C/sec and also features incremental/decremental segment holding for time and temperature. A unique spring device within the heated lid ensures contact is made with all sample tubes and self-adjusts to suit different sizes of tubes used in the various block options.
Thermolyne Amplitron II
The Amplitron II is a programmable thermal cycler that uses resistive heating elements and a compressor-driven, CFC-free cooling system for rapid and accurate temperature ramping. The Amplitron II comes with a 48-well 0.5 ml tube block and an optional heated lid or a 96-well 0.2 ml block with a standard heated lid. Also, all units can utilize an optional in situ slide plate. User-friendly software prompts quick and easy programming, with the Amplitron capable of storing 90 programs and linking up to 65. These units feature identification numbers for program protection, an auto-time feature that allows automatic time increases with each subsequent cycle, and a displayed temperature that emulates the actual sample temperature by use of a software compensation algorithm.
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