Capillary Array Electrophoresis Laser Focusing
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Capillary-array-electrophoresis devices face challenges in performing parallel electrophoresis analysis when using separation media with refractive indices between 1.33 and 1.41, as the multiple laser-beam focusing function is lost, limiting the number of capillaries that can be simultaneously irradiated and affecting analysis throughput and cost efficiency.
Innovation Solution
A capillary-array-electrophoresis device configuration with specific refractive index settings (n1=1.00, n2=1.46±0.01, n3<1.36, and R/r<5.9) ensures the convex lens function of capillaries, enabling simultaneous irradiation of multiple capillaries regardless of the separation medium's refractive index, including those close to 1.33, thereby expanding the device's application range and improving analysis throughput and cost efficiency.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If the separation medium has a refractive index between 1.33 and 1.41, then the device can use various separation media, but the multiple laser-beam focusing function is lost and the number of capillaries that can be simultaneously irradiated is limited
Solution Approach 1:
The patent changes the refractive index parameter of the external medium (n1) to match the refractive index of the capillary material (n2=1.46), creating a refractive index matching condition that eliminates refraction at the external medium-capillary interface. This parameter change allows the capillaries to function as convex lenses even when the separation medium has a refractive index between 1.33 and 1.41, thereby maintaining the multiple laser-beam focusing function while expanding compatibility with various separation media.
2Adaptability or versatility
If the refractive index of the separation medium is close to 1.33, then the device can analyze DNA in double-stranded state, but the convex lens function of capillaries is weakened and laser beam focusing fails
Solution Approach 1:
The patent introduces an external medium with refractive index n1=1.46 as an intermediary between the laser beam and the capillary. This external medium acts as a refractive index matching layer that compensates for the weak convex lens function when the separation medium has a low refractive index (n3≈1.33). By setting n1=n2=1.46, the patent eliminates refraction losses at the external medium-capillary interface, ensuring reliable laser beam focusing while enabling analysis of double-stranded DNA.
3Reliability
If both-side irradiation is used to enhance laser beam intensity, then the sum of intensities can be made uniform, but the device complexity increases
Solution Approach 1:
The patent segments the irradiation system into two independent laser light sources: one for one-side irradiation and one for both-side irradiation. Each laser light source can be independently controlled and optimized. This segmentation allows the device to achieve uniform laser beam intensity distribution across all capillaries while maintaining manageable system complexity through modular design and independent control of each irradiation path.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The proposed configuration allows for efficient electrophoresis analysis using various separation media, ensuring high throughput and low cost per sample by maintaining the convex lens function and multiple laser-beam focusing, even with low refractive index media, and enabling simultaneous irradiation of multiple capillaries.
Implementation Method 1
a refraction angle when the laser beam transmits through one capillary is expressed by the following Formula (1)... Each of the capillaries functions as a convex lens when Δθ<0 is satisfied
Implementation Method 2
Each of the capillaries functions as a convex lens when Δθ<0 is satisfied... the multiple laser-beam focusing technique... Each of the capillaries functions as a convex lens. The laser beam is repeatedly focused by the convex lenses along the array plane
Implementation Method 3
Laser-induced fluorescence from each of the capillaries is spectrally dispersed and simultaneously detected
Implementation Method 4
capillary-array-electrophoresis devices... to perform electrophoresis analysis in parallel... parallel electrophoresis analysis using 8 or 24 capillaries
Data Source
AI summary
When arraying laser-irradiation portions of a plurality of capillaries on the same array plane, simultaneous irradiation of the capillaries with a laser beam incident from the side is enabled by filling the capillaries with a separation medium having a low refractive index of n3<1.36 and by setting n1=1.00, n2=1.46, R/r<5.9, and ΔZ≤9 μm, wherein a distance in a direction perpendicular to the array plane between two capillaries, which are farthest from each other in the perpendicular direction among the capillaries in the laser-irradiation portions, is denoted by 2×ΔZ, wherein an outer radius, an inner radius, a refractive index of an external medium, a refractive index of a material, and a refractive index of an internal medium of each of the capillaries in the laser-irradiation portions are denoted by R, r, n1, n2, and n3, respectively.