Unique Benefits of the Small Beam Geometry of the Agilent Cary 60 UV-Visible Spectrophotometer

Importance of the Topic

The need to analyze tiny sample volumes with high sensitivity and minimal noise is growing in fields such as biochemistry, quality control and industrial analytics. A small, focused beam reduces stray light and maximizes light throughput, enabling accurate measurements even in challenging matrices. This approach directly addresses demands for high throughput, cost reduction and preservation of scarce or valuable samples.

Study Objectives and Overview

This technical note presents the unique optical design of the Agilent Cary 60 UV-Vis spectrophotometer. It highlights how its small beam geometry, based on a Xenon flash lamp, supports specialized accessories—ultra-microvolume and submicro cuvettes, fiber optic probes and remote diffuse reflectance—for versatile sample analysis both inside and outside the sample compartment.

Methodology and Instrumentation

• Instrument: Agilent Cary 60 UV-Visible Spectrophotometer featuring a patented Xenon flash lamp and a 1.5 mm × 1.0 mm focused beam.
• Accessories: Ultra-microvolume cuvette (2–10 µL), submicro cuvettes (10–135 µL aperture sizes 2.0 × 2.0 mm), fiber optic probe, fiber optic micro probe for microcentrifuge tubes, remote diffuse reflectance accessory (DRA) with 0/30° geometry and integrated video camera.

Key Results and Discussion

• Ultra-microvolume measurements achieved high photometric performance for 2–10 µL, with linear absorbance up to 2.3 Abs in a 1 mm pathlength (equivalent to 23 Abs in 10 mm), eliminating dilution steps for proteins like BSA.
• Submicro cuvettes provided reliable data for volumes from 10 to 135 µL, supporting high-concentration or highly absorbing solvents, with excellent temperature control due to efficient heat transfer.
• Fiber optic measurements maintained data quality regardless of ambient light, allowing liquid sampling from as low as 140 µL in microcentrifuge tubes and solids analysis up to 1.5 m away using the remote DRA.
• Remote DRA enabled fast, non-destructive diffuse reflectance spectra of small solid samples and color standards, leveraging a focused 1.5 mm light patch and internal detector.

Benefits and Practical Applications of the Method

• Maximized light throughput reduces noise and enhances sensitivity over a broad absorbance range.
• Small-volume capabilities accelerate workflows, cut reagent costs and preserve precious samples.
• Fiber optic sampling eliminates the need for cuvettes and sample compartment constraints, enabling in-situ measurements in fume hoods or challenging environments.
• Versatility allows one instrument to accommodate microvolumes, standard cuvettes and solid samples, streamlining laboratory operations.

Future Trends and Applications

With ongoing miniaturization and automation, small-beam UV-Vis spectrophotometry is set to integrate into high-throughput screening, inline process monitoring and portable field analysis. Advancements in fiber optics and accessory design will expand remote sensing capabilities for biomedical, environmental and manufacturing applications.

Conclusion

The Cary 60’s innovative small beam geometry delivers superior coupling efficiency and light utilization, enabling sensitive, flexible analysis of volumes from microliters to milliliters and remote solid samples. This versatility enhances productivity, reduces costs and meets the evolving needs of modern analytical laboratories.

Reference

Agilent Technologies. Unique Benefits of the Small Beam Geometry of the Agilent Cary 60 UV-Visible Spectrophotometer. Technical Note, Publication Number 5991-3852EN, 2014.
Agilent Technologies. Data Sheet #5990-7944EN.
Agilent Technologies. Application Notes #5990-7863EN, #5990-7945EN, #5991-1430EN.