Excellence in Melting Point Determination

Optimelt MPA100

Automated Melting Point Apparatus

  • Accurate measurements of melting point & melting range
  • Automatic and visual determination
  • PID-controlled temperature ramping
  • Digital movie of each melt
  • Stand-alone operation and computer control (USB)
  • Conforms to Pharmacopeia and GLP
  • Printer output



The MPA100 OptiMelt provides a fast and accurate means of automatically determining the melting points and melting ranges of chemical substances. With microprocessor-controlled temerature ramping, a built-in digital camera, and a selling price that is half that of competing models, OptiMelt offers the best value of any commercially available melting point apparatus.

Automated Measurements

OptiMelt is specifically designed for unattended operation. It has a built-in digital camera that continuously captures real-time images of the samples, and it uses digital image processing to determine results. The melting points and melting ranges are prominently displayed on the front panel and automatically recorded into memory for later review.

Simple Operation

OptiMelt has an intuitive front panel and is very easy to use. Simply select a start temperature, ramp rate, stop temperature, and hit start. Results can be easily seen from across the lab on the large LCD display.

Samples can be viewed on the front panel through a removable magnification lens. During a measurment, you can flag relevant events by pressing dedicated front-panel buttons. Up to six individual temperatures can be tagged for each sample.

Interactive help is available for all functions and parameters of the instrument. Text and numerical entry keypads are built into the touchscreen interface so that no external keyboard is required.

Distinct beeps and bright, front-panel LEDs announce important events like temperature stabilization or end of melt. Two separate glass holders, located on top of the instrument, are available to store empty or discarded capillary tubes.

Fast Measurements

The small, aluminum oven design, along with microprocessor-controlled temperature ramping, provides fast and repeatable warm-up and cool-down cycling. Programmable ramp rates from 0.1 C/min to 20 C/min, in 0.1 C/min increments, provide measurement flexibility.

The ability to rapidly preheat the oven to a start temperature slightly below an expected melting point minimizes analysis time.

Accurate Results

OptiMelt uses a platinum RTD sensor and makes temperature measurements to 400 C with 0.1C resolution. It is easily calibrated in the field against certified reference standards and complies with modern Pharmacopeia protocols. The instrument remembers the date of the last calibration which is included in all reports.

Data Logging

OptiMelt meets modern GLP requirements for melting point determination. Up to 24 different analysis methods can be stored in memory. Eight complete melting point reports can also be saved. Records can be displayed on the front panel, printed, or transferred to a host PC via USB. Printouts include technician identification and space for a signature.

Digital Image Processing

The OptiMelt system is unique among melting point analyzers. It has a built-in, high-resolution digital camera to capture real-time images of the samples. It then uses digital image processing to determine phase transitions in the samples.

Unattended melting points, and melting point ranges determined by OptiMelt, closely match visual results. OptiMelts digital image processing algorithm provides a dramatic improvement over optical absorption or reflection techniques.

MeltView Software

The MeltView Windows software displays live, high-resolution images of each sample during analysis.

The three screen-captured images to the right were collected during a typical melt. Figure 1 shows the unmelted solid samples, figure 2 reveals the meniscus point, and figure 3 corresponds to the end of the melt (clear point). Stored images may be recalled at any time, and can be played back frame-by-frame or as a movie.

Thermometer Input and Timers

OptiMelt is the only melting point apparatus that can also be used as a general-purpose digital thermometer and timer. In between melting point determinations, OptiMelt may be used with a Pt RTD to measure and log temperatures around the lab. Three built-in timers are also available to keep track of timed events during experiments.


Temperature display Melting point and melting point range
Start temp. range (Ambient + 10 C) to 396 C, 0 C min. set point
Stop temp. range
(Start temperature + 4 C) to 400 C
Temperature resolution 0.1 C
Ramp rate 0.1 C to 20 C per minute (0.1 C increments)
Heat-up time ~10 minutes (50 C to 350 C)
Cool-down time ~10 minutes (350 C to 50 C)
Temperature accuracy

±0.3 C (up to 100 C)
±0.5 C (up to 250 C)
±0.8 C (up to 400 C)
Reproducibility 0.2 C
Temperature sensor Pt RTD (built-in)
Oven control Closed-loop PID
Display Back-lit, touchscreen LCD (5.8")
Printer interface

RS-232 serial port. Supports Epson compatible dot-matrix printers
Computer interface

USB. All instrument functions can be queried and controlled through a high-level command set.
   Dimensions 1.4 mm to 2.0 mm outside dia., 100 mm length
   Capacity Up to 3 tubes simultaneously
   Fill height 2 mm to 3 mm
Power 90 to 264 VAC, 47 to 63 Hz, 125 W
Operating temperature 0 C to 40 C, non-condensing
Weight 4kg (9 lbs)
Dimensions 7.5" 10" 8.5" (WHL)

One year parts and labor on defects in materials and workmanship


The software for the Optimelt, called MeltView, is a Windows-based, easy to use acquisition and analysis package. It displays live, high-resolution images of each sample during analysis with accompanying melt graphs and also records movie files of each melt.

The video below shows a melting point determination of Phenacetin. This is stored on the PC and can be played back at any time, as a movie or frame by frame.

And here's the report:

Optimelt PC report

Below are some screen captures taken during a typical melting point determination.

melt 1

Figure 1: The unmelted solid samples are shown in the top part of the software, along with the melt graphs below

melt 2

Figure 2: This shows the meniscus point, which is used in the British Pharmacopeia

melt 3

Figure 3: Shows the end of the melt or clear point


There are three accessories available for the Optimelt:

Printer with cable and paper (O100P)

OP100P printer
The OP100P printer connects directly to the Optimelt and is used to print out a report once the melt is completed. The printed report lists all the relevant information pertaining to the melt including:

- date & time
- start, stop & halt temperature
- ramp rate
- chemical batch number & name
- onset, single and clear points
- graphs of the melt

Capillaries (O100MPC)

OP100MPC capillaries
OP100MPC contains 300 capillaries for use in the Optimelt. The capillaries are 1.5 - 1.8mm diameter and 90mm long. In a melt, three capillaries are used and each contains 2-3mm height of sample.

Melting point standards (O100MPS)

We can supply three melting point standards used to calibrate and check your Optimelt against your laboratory QA procedures. The three melting point standars cover the range of the instruement as follows:

- Low: Vanillin 83.0°C
- Medium: Phenacetin 135.9°C
- High: Caffeine 237.0°C