Semi-Micro Balances – Ultra-Precision Laboratory Weighing to 0.01 mg (10 μg)
Our semi-micro balances occupy the precision tier between analytical balances (0.1 mg readability) and true microbalances (0.001 mg readability), offering readability of 0.01 mg (10 micrograms) — ten times more sensitive than a standard analytical balance. With capacities typically from 52 g to 220 g, they are designed for applications where analytical balance resolution is insufficient but the extreme sensitivity of a microbalance is not required, making them the instrument of choice for pharmaceutical research, trace analysis, reference standard preparation, and advanced materials science.
At 0.01 mg resolution, environmental factors have a pronounced effect on weighing stability. Semi-micro balances are therefore equipped with advanced environmental protection as standard: motorised draft shield doors minimise air disturbance when loading samples, built-in anti-vibration systems compensate for bench and building vibration, anti-static ionisers neutralise electrostatic charge on samples and containers, and environmental sensors monitor temperature and humidity to flag conditions that could compromise measurement integrity. Automatic internal calibration using motorised reference weights ensures the balance self-corrects for temperature drift throughout the working day, maintaining accuracy without operator intervention.
Key Features
- Readability of 0.01 mg (10 μg) — ten times more sensitive than a standard analytical balance
- Capacities from 52 g to 220 g for micro-sample and reference standard weighing
- Automatic internal calibration with motorised reference weights for continuous accuracy
- Motorised draft shield doors to minimise air disturbance during sample loading
- Anti-vibration systems and environmental sensors for stable measurements in real laboratory conditions
- Anti-static ionisers to eliminate electrostatic interference on powders and fine samples
- GLP/GMP compliance features — audit trail, user management, and method documentation
- RS-232, USB, and Ethernet connectivity for LIMS, data logging, and printer integration
Common Applications
- Pharmaceutical research — API and potent compound weighing, micro-dosage formulation, and reference standard preparation
- Analytical chemistry — trace analysis, gravimetric determination, and high-precision sample preparation
- Biotechnology — DNA, protein, and enzyme weighing at microgram scale for molecular biology applications
- Materials science — thin film, coating weight, and nano-material mass determination
- Quality assurance — critical weighing for compliance testing, certified reference material preparation, and method validation
- Metrology — mass comparator and reference weight calibration applications
All semi-micro balances are sourced from leading laboratory instrument manufacturers and are available with UKAS-traceable calibration certificates on request. Contact our technical team for advice on selecting the right semi-micro balance for your application, environment, and regulatory requirements.
Frequently Asked Questions
What is the difference between a semi-micro balance and an analytical balance?
An analytical balance offers readability of 0.1 mg (0.0001 g). A semi-micro balance offers readability of 0.01 mg (0.00001 g) — ten times finer. Semi-micro balances also include more advanced environmental protection (motorised doors, ionisers, vibration compensation) as standard, reflecting the greater sensitivity required at this resolution. They are used when analytical balance resolution is insufficient for the weighing task.
What environmental conditions are required for accurate semi-micro balance readings?
Semi-micro balances require a stable, vibration-free surface (ideally an anti-vibration table), a draught-free and temperature-stable environment, and protection from electrostatic charge. Avoid siting near air conditioning vents, doors, windows, or high-traffic areas. Allow the balance to warm up for at least 30 minutes before use, and allow samples and containers to equilibrate to room temperature before weighing.
Do semi-micro balances comply with GLP and GMP requirements?
Yes. Most models include GLP/GMP compliance features including date/time stamping, user login and access management, audit trail logging, and method-guided weighing workflows. Full IQ/OQ/PQ validation documentation is available on request for pharmaceutical and regulated laboratory environments. Contact us to confirm the compliance features available on specific models.
How do I handle samples accurately at 0.01 mg resolution?
Use fine forceps or micro-spatulas to handle samples, and anti-static sample containers or weighing boats. Allow all items to equilibrate to room temperature before weighing. Use the tare function to zero out the container. Ensure the ioniser is active when weighing powders or fine particulates. Close the draft shield doors before taking a reading and wait for the stability indicator before recording the result.
Can I get a UKAS calibration certificate with my semi-micro balance?
Yes. UKAS-traceable calibration certificates are available on request for all semi-micro balances in our range. Annual recalibration by a qualified service engineer is strongly recommended, along with routine daily verification using certified reference weights. Contact our team for calibration and service support.
