1. Sample injection system

According to the sample morphology, it is divided into dry dispersion sampler and wet circulation sampler. The dry process system disperses powders through air jet, suitable for materials that are sensitive to solvents and prone to agglomeration; The wet process system suspends the sample in a liquid medium (such as water, ethanol) and achieves uniform dispersion through ultrasound and stirring, making it suitable for micronizing drugs and nano formulations. The sampler should have adjustable flow rate, anti settling design, and automatic cleaning function to ensure stable dispersion effect.

2. Light source and optical path system

Using high stability lasers (such as He Ne lasers with a wavelength of 632.8nm or semiconductor lasers) as illumination sources to ensure beam monochromaticity and coherence. The optical path design includes a beam expander, a collimator, and a Fourier lens, which shape the laser into parallel light to irradiate the sample and collect scattered light at all angles, providing a basis for subsequent signal analysis.

3. Detector array

Composed of multi ring or linearly arranged photoelectric detection units, covering forward, lateral, and backward scattering angles (usually 0.02 ° -150 °). High density detectors can capture subtle scattered light intensity distributions, enhancing their ability to distinguish between multi-modal distributions and submicron particles. Some instruments are equipped with Polarized Intensity Difference (PIDS) modules to enhance the detection sensitivity of submicron and nanometer particles.

4. Dispersed medium circulation system (wet process specific)

Includes circulating pump, ultrasonic device, constant temperature jacket, and filtration device. The circulation pump maintains uniform flow of the sample; Ultrasonic probe breaks down aggregates; Constant temperature control (such as 25 ℃) to avoid temperature fluctuations affecting particle size; The filter prevents residual particles from contaminating the next sample.

5. Data processing unit

Built in high-performance processor and professional software, based on MieTheory or Rayleigh scattering model, invert the scattered light intensity data collected by the detector into a particle size distribution curve. Support multiple report formats (volume distribution, quantity distribution), statistical parameters (D10, D50, D90), and multi method comparative analysis.

6. Control and operation interface

The drug particle size analyzer is equipped with a touch screen or PC software, allowing users to set test parameters, start programs, monitor dispersion status in real-time, and export audit trail reports that meet GMP/GLP requirements.