LED and UV lamp spectra

When measuring the absorbance of DNA or protein, UV-C LED can match the measurement performance of xenon flash lamp in a narrow wavelength range. Figure 2 compares the spectral irradiance of 1-mW, 260nm UV-C LED and 15W xenon flash.

Fig. 2 Power output of xenon flash lamp and UV-C LED at 260 nm. Spectral comparison shows that xenon flash lamp waste energy and high peak power of LED source.

The high-light output of the LED allows researchers to measure the concentration of double-stranded DNA (dsDNA) at a limit of 0.5 ng/ml, and the excellent spectral quality of the LED can be measured linearly in three orders of magnitude, from 0.5 to 2000 ng/ml.

The performance and monochromaticity of LEDs make the design of LEDs simpler than xenon flash instruments, requiring fewer optical components and thus reducing system costs. In addition, the power supply of UV-C LED is not so complex and the cost is low. Reducing the cost of components can produce more cost-effective instruments without sacrificing the performance of DNA purity measurements.

LED system efficiency

Component cost provides significant difference in initial system cost. However, system efficiency is also a factor leading to overall cost. In the system example given here, the power consumption of the UV-C LED system is about 2W (each LED 1W). The average power of the typical xenon flash is between 2W and 60W. In fact, the UV-C LED system provides a more efficient light source for fixed wavelength measurements. Since a large amount of light output from a xenon flash is filtered out at unnecessary wavelengths, as shown in Figure 2, the LED provides more power output at the desired wavelengths.

As shown here, systems using UV-C LEDs can match or even outperform those using UV lamps, while providing higher efficiency and lower costs for fixed-wavelength applications. Considerable performance allows instrument designers to take advantage of other advantages of UV-C LEDs, such as cost and size, without sacrificing product performance. UV-C LED can achieve longer instrument life, higher reliability and higher productivity, while reducing the overall cost of end-users. These new devices are driving innovation in the design of life science instruments to address market trends around productivity, cost reduction and miniaturization.