Portable Spectrofluorometer System and Method for Photoluminescence Analysis

Abstract

The present invention is to understand the nanomaterials at a laboratory level. Also, one step quick initial interaction about to study the basic experimental condition is mandatory. This requires a separate spectrofluorometers for labs to analyse synthesized nanoparticles and quantum dots. Thus, in-situ development of a portable cost-effective systems will enable students to qualitatively analyses the samples for individual understanding. The spectrofluorometer was developed and tested using known fluorescent nanomaterials like Iron Nanoclusters (FeQCs) and Carbon Quantum Dots (CQDs). The system was interfaced with optical filters with wavelength ranges of 500nm for FeQCs and 600nm for CQD to transmit only a specific wavelength of light to the detector. Using a diffraction grating with 1000 lines per mm, the incident light of 405 nm was split into its spectral components. The detector in the system was a CMOS sensor, capable of low-light detection, and the components were arranged in a straight line to the detector lens. Finally, the system was communicated to the open-source software Theremino to record the emission peaks from the fluorescent samples. The samples, which included CQD and FeQCs, were serially diluted. The emission peak was recorded between 572 nm for 100% concentrated CQD and the lowest concentration ratio of 1:8, which obtained the peak at 547 nm, which is referred to as sample 1. For sample 2 FeQCs, comparable peak values were obtained between 571 nm for a 1:2 ratio and decreasing the concentration to 1:8, and the peak was at 538 nm. The above emission wavelengths were also compared with a commercial spectrofluorometer, and analysis showed that the peak values of the two instruments were similar. The wavelength and transmission percentage were obtained as CSV files from the Theremino software, which further paved the way for us to determine the solution's absorbance. This invention can record nano samples, that it can be used to record peaks of any sample. Accompanied Drawing [FIG. 1] [FIG. 2] [FIG. 3] [FIG. 4] [FIG. 5] [FIG. 6] [FIG. 7] [FIG. 8]

Specification

Description:The following specification particularly describes the nature of the invention and the manner in which it is performed:
[01] FIELD OF THE INVENTION
The presently disclosed subject matter relates to systems, and devices for detecting, identifying, and quantifying optical systems and components in optical instrumentation.
[02] BACKGROUND OF INVENTION
The characteristic spectra of the samples must be observed from spectrofluorometers in order to understand the emission characteristics of the sample, since it is a time-consuming process and requires several procedures, it is not feasible in all laboratories. Low-cost spectrofluorometers were operated with open-source software, where biomaterials have been used for the analysis of instrumentation, which has been changed from the existing ones according to the samples placed, and the capture of spectra generally requires expensive and specialized equipment before the emergence of low-cost DIY spectrofluorometers utilizing open-source software, such as Theremino. This makes it difficult for many researchers to perform spectroscopic experiments, especially those with limited resources. While there are some low-cost commercial options available, their performance is often limited compared to that of more expensive equipment. However, with the emergence of open-source software, such as Theremino, and platforms, such as MIT app inventors, researchers have been able to develop more affordable and accessible spectrofluorometers. This low-cost equipment was enclosed in cardboard and wooden boxes where IR radiation passes through it and has given human errors in the results, although this has enabled a wider range of scientists to conduct spectroscopy experiments and has opened new possibilities for research in various fields. The sample size limitations were set in the existing models.
[03] SUMMARY OF THE INVENTION
The invention offers significant advantages over existing technologies, primarily in terms of cost-effectiveness, high-quality imaging capabilities, and enhanced flexibility and control.
Improved Instrumentation and Alignment: The present invention introduces novel instrumentation and alignment techniques, which contribute to enhanced performance and accuracy. The use of a diffraction grating with 1000 lines per mm, long pass optic filters in a range of 500nm and 600nm , and a laser source of 405nm as an alternative to a broad band excitation source improves the spectral resolution and signal-to-noise ratio of the instrument. This advancement ensures better sensitivity and accuracy in fluorescence measurements compared to traditional techniques.
Analysis of Nano Materials: The invention incorporates the analysis of nano materials, such as carbon quantum dots and iron nano clusters, as samples. This represents a significant improvement over existing technologies that may not have focused extensively on the analysis of fluorescence in nano-scale materials. By specifically targeting the detection and characterization of nano materials, the invention opens up new possibilities for studying and understanding the unique photoluminescent properties of these materials.
Concentration Analysis: It employs serial dilution of the samples to identify their efficiency. By systematically reducing the sample concentration, the invention can accurately assess the fluorescence characteristics across a range of concentrations. This approach allows for a comprehensive analysis of fluorescence properties and provides insights into the sensitivity and dynamic range of the instrument.
[04] OBJECT OF THE INVENTION
The proposed spectrofluorometer introduces a novel design and alignment, departing from existing instrumentation in the literature. It incorporates essential components, such as a web camera, diffraction grating with 1000 lines per mm, long-pass optical filters, and a laser source.
Unlike previous techniques using broadband light sources, the invention utilizes a laser light source (405 nm), minimizing the excessive dissipation of charges entering the detector. This innovative approach enhances the sensitivity and resolution of fluorescence analysis.
The placement of optical components with precise measurements and slots facilitated by 3D printing ensures optimal alignment and performance. The entire optical setup was enclosed in a black box to minimize stray light interference and enhance the sensitivity.
The invention utilizes nanomaterials, specifically carbon quantum dots and iron nanoclusters (2 nm-10 nm), as samples for analysis. This unique feature enables the detection and analysis of fluorescence from nanoscale materials, enhancing sensitivity and resolution.
To assess sample efficiency, the invention employed a serial dilution method, systematically reducing sample concentrations for performance evaluation. This approach provides valuable insights into the fluorescence characteristics and behavior across a range of concentrations.
The optical components are enclosed in a black box made of hylem sheets, further minimizing stray-light interference and enhancing sensitivity. This design choice ensures precise and reliable fluorescence measurements.
The inclusion of a laser light source, customized 3D printed alignment, utilization of nanomaterials, serial dilution method, and black box enclosure differentiate this invention from the existing literature, contributing to advancements in fluorescence analysis with enhanced sensitivity and resolution.
[05] BRIEF DESCRIPTION OF THE DRAWINGS
The invention will be better understood and objects other than those set forth above will become apparent when consideration is given to the following detailed description thereof. Such description refers to the annexed drawings wherein:
Figure 1: Block diagram representation of developed spectrofluorometer
Figure 2 : Distance and design overview of 3D printed slots (Designed using AUTOCAD
Figure 3: Internal view of developed spectrofluorometer with optical components placed
Figure 4: Theremino software interfaced with developed spectrofluoremeter image captured
Figure 5: Serial dilution of the nano fluorescent probe with dilution factor of 2
during spectrum acquisition in their respective slots software)
Figure 6: Electromagnetic spectral output of carbon quantum dots with the proposed model and commercial spectrofluorometer with dilution 1:2,1:4,1:8
Figure 7: Electromagnetic spectral output of iron nano clusters with the proposed model and
commercial spectrofluorometer (a), (b) with dilution 1:2 ,1:4 and 1:8
Figure 8: Internal view of developed spectrofluorometer with optical components placed in their respective slots

[06] DETAILED DESCRIPTION OF THE INVENTION
The invention herein pertains to a novel spectrofluorometer meticulously designed for laboratory applications. This innovative device stands out for its portability and self-contained design, which ingeniously integrates essential optical elements within a 3D printed framework. Leveraging multiple outputs from visualization software, specifically Theremino, facilitates the precise placement of components at predetermined distances.
The primary objective of this invention was to streamline the identification and analysis of samples based on their fluorescence efficiency. A spectrofluorometer enables the characterization of previously unknown substances by gauging the transmission of samples and scrutinizing their photoluminescence properties. The device was validated using nanoparticles ranging from 2 nm to 10 nm, which were serially diluted to ascertain samples at varying fluorescence emission levels.
This pioneering device was developed through a series of key steps. First, meticulous procurement and alignment of optical components within the 3D printed structure were paramount to ensure operational integrity of the spectrofluorometer. Subsequent efforts were directed towards characterizing the performance of the device using fluorescent probes, providing insights into its capabilities for fluorescence analysis and detection.
The conclusive phase centered on rigorous testing and validation was accomplished through a meticulous comparison of results with a recognized standard commercial spectrofluorometer, facilitated by the Theremino software. The successful execution of this step validates the reliability of the invention and its capacity to deliver desired results.
A 405nm laser light source placed closer to the cuvette triggered the sample. The diffraction grating was situated 4cm apart from the sample holder and 0.2mm away from the long pass filters. These were put closer to the detector's lens, at a distance of 0.1mm. These were placed to the lens of the detector with 2cm distance. The whole projection of the sample to be analysed was adjusted in the software by varying x and y axis plots.
The spectrofluorometer's box design was developed using AutoCAD software based on the sizes and separation of the optical components, as shown in Fig. 8. Furthermore, PLA is a lightweight polymer with low reflectivity that prevents IR radiation from entering its internal environment, making it perfect for a portable optical device.
All of the parts with corresponding slots were properly glued inside the box. A slot was found to alter the optical filters based on the emission range recorded. (either 500nm or 600nm long pass). The detector has been connected to Theremino software, an open-source programme. The user interface of Theremino displays the web camera's view in a succession of frames at a rate of 30 frames per second. (fps). Theremino also aids in the real-time presentation of transmission peaks in the electromagnetic spectrum with wavelengths ranging from 200 to 1000 nm.
When light is incident on the cuvette sample, the fluorescent molecules, carbon quantum dots, and iron nanoclusters that display photoluminescence characteristics will shift from the ground state to the excited state. Individual analyses were conducted on carbon quantum dots that had been diluted with water diluent at dilutions of 1:2, 1:4, and 1:8. A 405nm laser source was used to stimulate the sample inside the cuvette. A diffraction grating with 1000 lines per mm is then used to diffract the light that was transmitted from the sample.
Iron nano clusters were employed with a 500 nm long pass optical filter, while carbon quantum dots solution was used with a 600 nm long pass optical filter as shown in figure 6. The images were captured with a web camera, and Theremino software was used to visualize the spectrum. The resulting emission spectrum and transmission percentage was obtained as CSV files. For a given desired range, the X axis and Y axis limits could be modified for a particular region detection. The widely available Photoluminescence Spectrophotometer FLS 1000, made by Edinburgh Instruments, was used to validate the proposed spectrofluorometer
The emission spectrum of Carbon quantum dots sample solution obtained by the developed spectrofluorometer is shown where X-axis denotes wavelength and Y-axis indicates percentage of fluorescence transmission %. Spectral peak observed with the developed spectrofluorometer starts at 572nm with fluorescence emission of 96.3%. The wavelength at which the peaks were detected and the corresponding fluorescence emission peaks are tabulated in Table .The same samples were used for peak acquisition of the commercial spectrofluorometer for comparison. The excitation at 395nm was provided with commercial spectrofluorometer. The acquisition of the spectrum for fully concentrated samples using commercial product starts at 590nm and ends at 750nm this was shown below.
Another fluorescent material, iron nano clusters termed as sample 2, was taken into consideration to further assess the capability of the constructed device. The samples were serially diluted using the same CQD-considered dilution factor. The constructed 3D spectrofluorometer was used to examine all three of the diluted samples, and the outcomes were compared to those obtained using a commercial spectrofluorometer. The only difference between the spectrofluorometer configuration used for the CQD investigation was the use of a 500nm optical filter instead of a 600nm filter. Between 400 and 580 nm, iron nano cluster emission was seen in the samples. Resultant spectrum images with developed system are shown in figure 7, 8 and Edinburgh photoluminescence spectrophotometer FLS 1000 .
Sample
CQD&FeQCs Peaks observed with the developed device (nm)
Fluorescence emission values(%) Exhibition of peaks from the commercial product
CQD FeQCs CQD FeQCs CQD FeQCs
Without dilution 572 - 96.3 - Starts:600nm
Ends:750nm -
1:2 dilution 554 571 90.2 86.2 Starts:590nm
Ends:750nm Starts:580nm
Ends:740nm
1:4 dilution 554 570 80.3 22.0 Starts:585nm
Ends:750nm Starts:580nm
Ends:740nm
1:8 dilution 547 538 52.9 3.1 Starts:580nm
Ends:750nm Starts:580nm
Ends:740nm

Tabulation of Fluorescence emission peaks of Carbon quantum dots &Iron nano clusters

This invention represents a significant advancement in spectrofluorometry, offering enhanced affordability and accessibility across diverse laboratory settings. Its impact extends beyond mere cost-effectiveness, paving the way for researchers and scientists to harness its benefits in their endeavors.
[07] IMPACT OF THE INVENTION
The impact of an apparatus designed to analyze synthesized nanoparticles and quantum dots is profound, influencing various fields of science, technology, and industry. First, it enhances research and innovation by providing accurate tools for characterizing the size, shape, and unique properties of nanoparticles and quantum dots. This accelerates discoveries in nanotechnology and facilitates the development of advanced materials with tailored properties for specific applications.
Second, the invention significantly improves quality control and standardization in industries such as electronics, energy, healthcare, and environmental science. High-precision analysis ensures that products, including quantum dot displays, solar cells, and nanomedicines, meet stringent performance and safety standards.
Third, it advances quantum and nanotechnology applications by enabling a deeper understanding of quantum confinement and nanoscale interactions. This fosters progress in areas such as quantum computing, bio-imaging, and next-generation sensors.
Fourth, the apparatus contributes to environmental and toxicological studies, helping researchers understand the behavior and impact of nanoparticles in various ecosystems. This supports the development of safer and more sustainable applications of nanomaterials.
Finally, the apparatus has a multidisciplinary impact, bridging gaps between fields like physics, chemistry, biology, and materials science. By empowering researchers and industries to analyze and optimize nanoparticles and quantum dots, the invention drives innovation, improves material performance, and opens new frontiers in science and technology.
[08] MOTIVATION OF INVENTION
The invention of an apparatus to analyze synthesized nanoparticles and quantum dots is driven by the need for precise characterization and a deeper understanding of these advanced materials. Nanoparticles and quantum dots exhibit unique properties, such as optical, electronic, and magnetic behaviors, which are highly dependent on their size, shape, composition, and surface chemistry. Accurate analysis of these properties is essential for ensuring reproducibility, optimizing functionality, and supporting cutting-edge research in nanotechnology. This apparatus is also crucial for quality control in industries like electronics, medicine, and energy, where these materials are used in products such as displays, solar cells, and drug delivery systems. Furthermore, understanding the quantum confinement effects in quantum dots and their interactions in various environments facilitates innovations in quantum physics, interdisciplinary applications, and environmental safety studies. By providing insights into synthesis challenges, this apparatus helps refine production processes and tailor materials to specific applications, promoting breakthroughs in materials science and enabling the sustainable and reliable use of nanoparticles and quantum dots.
, Claims:I/We claim
1. A portable spectrofluorometer system comprising:
(a) a 405 nm laser light source configured to excite a sample placed within a cuvette;
(b) a diffraction grating with 1000 lines per millimeter, positioned at a fixed distance from the cuvette to diffract light transmitted from the sample;
(c) one or more long-pass optical filters, interchangeable via a slot mechanism, configured to selectively filter light based on emission wavelengths;
(d) a detector comprising a web camera, positioned to capture light passed through the optical filters and configured to record images at a rate of 30 frames per second;
(e) a casing made of a lightweight, low-reflectivity polymer to house the components and prevent infrared radiation from entering the system;
(f) software configured to visualize, analyze, and export transmission and emission spectra in real time; wherein the system is capable of detecting photoluminescence properties of fluorescent molecules across a wavelength range of 200 to 1000 nm.
2. The spectrofluorometer system of Claim 1, wherein the polymer casing is constructed using polylactic acid (PLA) to provide lightweight and thermally insulating properties.
3. The spectrofluorometer system of Claim 1, further comprising:
a software-controlled mechanism to adjust the X-axis and Y-axis limits for region-specific detection and spectrum analysis.
4. The spectrofluorometer system of Claim 1, wherein the long-pass optical filters include filters with cutoff wavelengths of 500 nm and 600 nm, each optimized for analyzing specific emission ranges of iron nanoclusters and carbon quantum dots, respectively.
5. The spectrofluorometer system of Claim 1, wherein the detector is operably connected to an open-source software interface for real-time visualization of transmission peaks and for exporting captured spectral data as CSV files.
6. The spectrofluorometer system of Claim 1, wherein the interchangeable optical filters are positioned at a distance of 0.2 mm from the diffraction grating and 0.1 mm from the detector lens to enhance spectral resolution.
7. The spectrofluorometer system of Claim 1, further comprising an AutoCAD-designed modular casing that incorporates dedicated slots and supports for precise alignment of optical components.
8. A method of analyzing photoluminescence properties using the spectrofluorometer system of Claim 1, comprising the steps of:
(a) placing a sample in the cuvette;
(b) exciting the sample using the 405 nm laser light source;
(c) diffracting emitted light through the diffraction grating;
(d) filtering the diffracted light through the selected long-pass optical filter;
(e) capturing the filtered light using the detector; and
(f) visualizing and exporting the spectral data using the connected software.
9. The method of Claim 8, wherein the sample comprises carbon quantum dots diluted with water at predetermined dilutions of 1:2, 1:4, and 1:8.
10. The method of Claim 8, further including the step of validating the captured spectral data against a commercial photoluminescence spectrophotometer.

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