A New Analytic Approach for "Phase-Shifting” π-Systems Using Resonance Raman Scattering
- 주제(키워드) 공명라만현상 , 폴리다이아세틸렌
- 발행기관 고려대학교 대학원
- 지도교수 안동준
- 발행년도 2015
- 학위수여년월 2015. 2
- 학위구분 석사
- 학과 일반대학원 화공생명공학과
- 세부전공 화공생명공학전공
- 원문페이지 101 p
- 실제URI http://www.dcollection.net/handler/korea/000000057112
- 본문언어 영어
- 제출원본 000045828270
초록/요약
In recent years, Resonance Raman spectroscopy has been a powerful spectroscopic tool for analyzing various π-conjugated systems in terms of vibrational and electronic properties. Examples of π-conjugated materials include graphene, silicon, and conjugated polymers. Among the various conjugated polymers, polydiacetylenes (PDAs) have been extensively researched in the field of chemical and biological sensor as they undergo a blue-to-red color transition and non-fluorescent to red-fluorescent in response to external stimulus such as temperature, pH, chemical solvent, and ligand-receptor interaction. Such optical and vibrational properties of PDAs have been analyzed by visible absorption and fluorescence spectra. In this thesis, the in-situ Raman analysis of PDA vesicles with phase-shifting characteristics using dual-wavelength Raman scattering mode is investigated. Raman intensities of PDA system are also quantified in order to evaluate the thermochromic transition. Further, a new sensing platform of PDA vesicles using Resonance Raman spectroscopy is introduced as we have successfully detected cyclodextrins and heavy metals, respectively.
more목차
1. Introduction 1
1.1. Research background 1
1.2. Raman spectroscopy 3
1.3. Resonance Raman spectroscopy 5
1.4. Conjugated polymer 7
1.5. Polydiacetylene (PDA) 8
1.6. Phase-shifting characteristics of PDA 12
1.7. Colorimetric Response (CR) 14
1.8. Calculation of fluorescence in Raman spectroscopy 15
1.9. Objective 16
2. Experimental Section 17
2.1. Materials 17
2.1.1. Reagents 17
2.1.2. Diacetylene derivatives 17
2.1.3. Cyclodextrin (CD) 19
2.1.4. Heavy metals 21
2.2. Sample preparation 23
2.2.1. Preparation of polydiacetylene vesicles 23
2.2.2. Preparation of cyclodextrin solution 23
2.2.3. Preparation of heavy metals 23
2.3. Measurements 25
2.3.1. Raman spectroscopy 25
2.3.2. UV-visible spectroscopy and fluorescence spectroscopy 25
2.3.3. Other instruments 26
3. Results and Discussion 28
3.1. Resonance Raman study of phase-shifting polydiacetylene 28
3.1.1. Morphology and size analysis 28
3.1.2. Resonance Raman spectra of PDA vesicles 30
3.1.3. Fluorescent-resonance Raman spectra of PDA vesicles 32
3.1.4. quantification of Raman intensity 35
3.1.5. Normal Raman spectra of PDA vesicles 38
3.1.6. Ex-situ Raman spectra of PDA vesicles 40
3.1.7. Quantification of overall Raman spectroscopy 44
3.2. Unusual phase-shifting characteristics of PDA 46
3.2.1. Resonance Raman scattering effect of yellow phase PDA... 46
3.2.2. Quantitiative analysis of PDA with CTAB surfactant 51
3.2.3. Raman spectra analysis of PDA with SDS surfactant 54
3.3. Raman sensing performance 58
3.3.1. Detection of cyclodextrins 61
3.3.1.1. Quantitative analysis of cyclodextrin 65.
3.3.2. Detection of heavy metals 68
3.3.2.1. Bulk analyses of probing heavy metals 69
3.3.2.2. Detection of heavy metals in liquid state 74
3.3.2.4. Limitation in Raman sensing probe for heavy metals.. 78
4. Conclusion 79
REFERENCES 82
