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Morita T, Torii Y, Imamura H, Kadota T, Sakuma F, Higashi K, Sumi T. Pair Potential between Poloxamer 407 Micelles in 14 wt % Aqueous Solution Clarifying the Sol-Gel-Sol Transition by Temperature Rise. J Phys Chem Lett 2024:7909-7915. [PMID: 39066786 DOI: 10.1021/acs.jpclett.4c01138] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/30/2024]
Abstract
Poloxamer 407 (P407) is used as a safety-guaranteed, invaluable pharmaceutical nanocarrier. The aqueous solution of P407 exhibits sol-to-gel and gel-to-sol transitions, specifically during a temperature rise. Here, we develop a method to determine the pair potential between colloidal particles based primarily on experimental small-angle scattering data. Using this approach, the pair potential between the P407 micelles in the sol-gel-sol transition state is revealed without prelimiting any type of interaction forces. The results indicate that the increase in the attractive interaction contributes to enhancing the volume fraction, which is the decisive parameter for the gelation in terms of the Alder transition theory, i.e., the fluid-to-crystal phase transition of the hard-sphere model in the micelle system. This study demonstrates that one of the key mechanisms of the gel-to-sol transition upon heating is the enhancement of the structural fluctuation due to widening of the potential well in the intermicellar pair potential.
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Affiliation(s)
- Takeshi Morita
- Graduate School of Science, Chiba University, Chiba 263-8522, Japan
| | - Yusuke Torii
- Graduate School of Science, Chiba University, Chiba 263-8522, Japan
| | - Hiroshi Imamura
- Department of Biological Data Science, Nagahama Institute of Bio-Science and Technology, Nagahama 526-0829, Shiga, Japan
| | - Teruki Kadota
- Graduate School of Science, Chiba University, Chiba 263-8522, Japan
| | - Fumie Sakuma
- Graduate School of Pharmaceutical Sciences, Chiba University, Chiba 260-8675, Japan
| | - Kenjirou Higashi
- Graduate School of Pharmaceutical Sciences, Chiba University, Chiba 260-8675, Japan
| | - Tomonari Sumi
- Research Institute for Interdisciplinary Science, Okayama University, Okayama 700-8530, Japan
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Sakuma F, Higashi K, Ueda K, Morita T, Iohara D, Hirayama F, Moribe K. Effect of Acetaminophen on Poloxamer 407 Micelles and Hydrogels: The Relationship between Structural and Physical Properties. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2024. [PMID: 39012334 DOI: 10.1021/acs.langmuir.4c01362] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/17/2024]
Abstract
Poloxamer hydrogel possesses thermosensitive sol-gel transition characteristics and is widely used as a drug-controlled-release carrier for topical or injectable formulations. In this study, the effect of loading of a drug, acetaminophen (ACE), on the physical and structural properties of poloxamer 407 (P407) micelles and hydrogels was investigated. Differential scanning calorimetry measurements revealed that ACE reduced the critical micelle temperature and enthalpy of micellization of P407 solutions. The P407 micellization was promoted by ACE incorporation. Rheometry showed that ACE increased the sol-gel transition temperature and reduced the gel strength of P407. In situ small-angle X-ray scattering (SAXS) using synchrotron radiation revealed that ACE altered the structure of P407 micelles and their packing in the P407 gels. As ACE concentration increased, the P407 micelle packing changed from a face-centered cubic phase to a body-centered cubic phase. Furthermore, ACE disordered the micelle packing structure and induced the formation of an amorphous phase. Structural analysis of the P407 micelle packing indicated that ACE reduced the aggregation number (Nagg) of P407 micelles in the gels. The SAXS study for diluted P407 solutions revealed that ACE reduced the P407 micelle size and its uniformity. The structural changes in P407 micelles by ACE loading (e.g., the reduction of Nagg, size, and size uniformity) would alter the micelle packing structure. It was found that these structural changes of micelle packing, especially the formation of an amorphous phase, could destabilize the P407 gel. As a result, the physical properties of P407 gels, such as gelation temperature and gel strength, were changed. This relationship between the structure and physical property of drug-loaded P407 gels was well-explained by correlating the micelle and gel structures. The mechanistic understanding of the change in the physical properties of P407 gels by drug loading is essential for the effective development of poloxamer gel formulations.
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Affiliation(s)
- Fumie Sakuma
- Graduate School of Pharmaceutical Sciences, Chiba University, 1-8-1, Inohana, Chuo-ku, Chiba 260-8675, Japan
| | - Kenjirou Higashi
- Graduate School of Pharmaceutical Sciences, Chiba University, 1-8-1, Inohana, Chuo-ku, Chiba 260-8675, Japan
| | - Keisuke Ueda
- Graduate School of Pharmaceutical Sciences, Chiba University, 1-8-1, Inohana, Chuo-ku, Chiba 260-8675, Japan
| | - Takeshi Morita
- Graduate School of Science, Chiba University, 1-33, Yayoi-cho, Inage-ku, Chiba 263-8522, Japan
| | - Daisuke Iohara
- Faculty of Pharmaceutical Sciences, Sojo University, 4-22-1, Ikeda, Nishi-ku, Kumamoto 860-0082, Japan
| | - Fumitoshi Hirayama
- Faculty of Pharmaceutical Sciences, Sojo University, 4-22-1, Ikeda, Nishi-ku, Kumamoto 860-0082, Japan
| | - Kunikazu Moribe
- Graduate School of Pharmaceutical Sciences, Chiba University, 1-8-1, Inohana, Chuo-ku, Chiba 260-8675, Japan
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Liu H, Guo Z, Ma W, Li S, Wang D, Zheng Z, Liu Y, Yu CY, Wei H. UV Irradiation-Induced Cyclic-to-Linear Topological Changes of a Light/pH Dual-Sensitive Cyclic Copolymer for Enhanced Drug Delivery. ACS Macro Lett 2023; 12:1025-1030. [PMID: 37432938 DOI: 10.1021/acsmacrolett.3c00265] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/13/2023]
Abstract
Cyclic polymers with cleavable backbones triggered by either external or internal stimuli can realize simultaneous extracellular stability and intracellular destabilization of cyclic polymer-based nanocarriers but remain seldom reported. To this end, we prepared herein cyclic-ONB-P(OEGMA-st-DMAEMA) (c-ONB-P(OEGMA-st-DMAEMA)) with a light-cleavable junction in the polymer backbone based on oligo (ethylene glycol) monomethyl ether methacrylate (OEGMA) and N,N-dimethylaminoethyl methacrylate (DMAEMA) using a light-cleavable atom transfer radical polymerization (ATRP) initiator containing an o-nitrobenzyl (ONB) ester group. Together with the pH-sensitivity of DMAEMA, c-ONB-P(OEGMA-st-DMAEMA) shows a light-cleavable mainchain and pH-sensitive side chains. Notably, doxorubicin (DOX)-loaded c-ONB-P(OEGMA4-st-DMAEMA38) (C2) micelles mediated an IC50 value of 2.28 μg/mL in Bel-7402 cells, which is 1.7-fold lower than that acquired without UV irradiation. This study thus reported the synthesis of a cyclic copolymer with a UV-cleavable backbone and uncovered the effects of topological modulation on the in vitro controlled release properties of cyclic polymers.
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Affiliation(s)
- Hongbing Liu
- Hunan Province Cooperative Innovation Center for Molecular Target New Drug Study & Department of Pharmacy and Pharmacology, University of South China, Hengyang 421001, China
| | - Zheng Guo
- Hunan Province Cooperative Innovation Center for Molecular Target New Drug Study & Department of Pharmacy and Pharmacology, University of South China, Hengyang 421001, China
| | - Wei Ma
- Hunan Province Cooperative Innovation Center for Molecular Target New Drug Study & Department of Pharmacy and Pharmacology, University of South China, Hengyang 421001, China
| | - Shuang Li
- Hunan Province Cooperative Innovation Center for Molecular Target New Drug Study & Department of Pharmacy and Pharmacology, University of South China, Hengyang 421001, China
| | - Dun Wang
- Hunan Province Cooperative Innovation Center for Molecular Target New Drug Study & Department of Pharmacy and Pharmacology, University of South China, Hengyang 421001, China
| | - Zhi Zheng
- Hunan Province Cooperative Innovation Center for Molecular Target New Drug Study & Department of Pharmacy and Pharmacology, University of South China, Hengyang 421001, China
| | - Ying Liu
- Hunan Province Cooperative Innovation Center for Molecular Target New Drug Study & Department of Pharmacy and Pharmacology, University of South China, Hengyang 421001, China
| | - Cui-Yun Yu
- Hunan Province Cooperative Innovation Center for Molecular Target New Drug Study & Department of Pharmacy and Pharmacology, University of South China, Hengyang 421001, China
| | - Hua Wei
- Hunan Province Cooperative Innovation Center for Molecular Target New Drug Study & Department of Pharmacy and Pharmacology, University of South China, Hengyang 421001, China
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Zhu JQ, Wu H, Li ZL, Xu XF, Xing H, Wang MD, Jia HD, Liang L, Li C, Sun LY, Wang YG, Shen F, Huang DS, Yang T. Responsive Hydrogels Based on Triggered Click Reactions for Liver Cancer. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2022; 34:e2201651. [PMID: 35583434 DOI: 10.1002/adma.202201651] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/20/2022] [Revised: 05/11/2022] [Indexed: 06/15/2023]
Abstract
Globally, liver cancer, which is one of the major cancers worldwide, has attracted the growing attention of technological researchers for its high mortality and limited treatment options. Hydrogels are soft 3D network materials containing a large number of hydrophilic monomers. By adding moieties such as nitrobenzyl groups to the network structure of a cross-linked nanocomposite hydrogel, the click reaction improves drug-release efficiency in vivo, which improves the survival rate and prolongs the survival time of liver cancer patients. The application of a nanocomposite hydrogel drug delivery system can not only enrich the drug concentration at the tumor site for a long time but also effectively prevents the distant metastasis of residual tumor cells. At present, a large number of researches have been working toward the construction of responsive nanocomposite hydrogel drug delivery systems, but there are few comprehensive articles to systematically summarize these discoveries. Here, this systematic review summarizes the synthesis methods and related applications of nanocomposite responsive hydrogels with actions to external or internal physiological stimuli. With different physical or chemical stimuli, the structural unit rearrangement and the controlled release of drugs can be used for responsive drug delivery in different states.
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Affiliation(s)
- Jia-Qi Zhu
- The Key Laboratory of Tumor Molecular Diagnosis and Individualized Medicine of Zhejiang Province, Zhejiang Provincial People's Hospital (People's Hospital of Hangzhou Medical College), Hangzhou, Zhejiang, 310014, China
- College of Biotechnology and Bioengineering, Zhejiang University of Technology, Hangzhou, Zhejiang, 310014, China
| | - Han Wu
- The Key Laboratory of Tumor Molecular Diagnosis and Individualized Medicine of Zhejiang Province, Zhejiang Provincial People's Hospital (People's Hospital of Hangzhou Medical College), Hangzhou, Zhejiang, 310014, China
- Department of Hepatobiliary Surgery, Eastern Hepatobiliary Surgery Hospital, Second Military Medical University (Naval Medical University), Shanghai, 200438, China
| | - Zhen-Li Li
- The Key Laboratory of Tumor Molecular Diagnosis and Individualized Medicine of Zhejiang Province, Zhejiang Provincial People's Hospital (People's Hospital of Hangzhou Medical College), Hangzhou, Zhejiang, 310014, China
- Department of Hepatobiliary Surgery, Eastern Hepatobiliary Surgery Hospital, Second Military Medical University (Naval Medical University), Shanghai, 200438, China
| | - Xin-Fei Xu
- Department of Hepatobiliary Surgery, Eastern Hepatobiliary Surgery Hospital, Second Military Medical University (Naval Medical University), Shanghai, 200438, China
| | - Hao Xing
- Department of Hepatobiliary Surgery, Eastern Hepatobiliary Surgery Hospital, Second Military Medical University (Naval Medical University), Shanghai, 200438, China
| | - Ming-Da Wang
- Department of Hepatobiliary Surgery, Eastern Hepatobiliary Surgery Hospital, Second Military Medical University (Naval Medical University), Shanghai, 200438, China
| | - Hang-Dong Jia
- The Key Laboratory of Tumor Molecular Diagnosis and Individualized Medicine of Zhejiang Province, Zhejiang Provincial People's Hospital (People's Hospital of Hangzhou Medical College), Hangzhou, Zhejiang, 310014, China
| | - Lei Liang
- The Key Laboratory of Tumor Molecular Diagnosis and Individualized Medicine of Zhejiang Province, Zhejiang Provincial People's Hospital (People's Hospital of Hangzhou Medical College), Hangzhou, Zhejiang, 310014, China
| | - Chao Li
- Department of Hepatobiliary Surgery, Eastern Hepatobiliary Surgery Hospital, Second Military Medical University (Naval Medical University), Shanghai, 200438, China
| | - Li-Yang Sun
- The Key Laboratory of Tumor Molecular Diagnosis and Individualized Medicine of Zhejiang Province, Zhejiang Provincial People's Hospital (People's Hospital of Hangzhou Medical College), Hangzhou, Zhejiang, 310014, China
| | - Yu-Guang Wang
- College of Biotechnology and Bioengineering, Zhejiang University of Technology, Hangzhou, Zhejiang, 310014, China
| | - Feng Shen
- Department of Hepatobiliary Surgery, Eastern Hepatobiliary Surgery Hospital, Second Military Medical University (Naval Medical University), Shanghai, 200438, China
| | - Dong-Sheng Huang
- The Key Laboratory of Tumor Molecular Diagnosis and Individualized Medicine of Zhejiang Province, Zhejiang Provincial People's Hospital (People's Hospital of Hangzhou Medical College), Hangzhou, Zhejiang, 310014, China
- School of Clinical Medicine, Hangzhou Medical College, Hangzhou, Zhejiang, 310014, China
| | - Tian Yang
- The Key Laboratory of Tumor Molecular Diagnosis and Individualized Medicine of Zhejiang Province, Zhejiang Provincial People's Hospital (People's Hospital of Hangzhou Medical College), Hangzhou, Zhejiang, 310014, China
- Department of Hepatobiliary Surgery, Eastern Hepatobiliary Surgery Hospital, Second Military Medical University (Naval Medical University), Shanghai, 200438, China
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Uchiyama H, Kadota K, Tozuka Y. A review of transglycosylated compounds as food additives to enhance the solubility and oral absorption of hydrophobic compounds in nutraceuticals and pharmaceuticals. Crit Rev Food Sci Nutr 2022; 63:11226-11243. [PMID: 35757865 DOI: 10.1080/10408398.2022.2092056] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Transglycosylation has been used to modify the physicochemical properties of original compounds. As a result, transglycosylated compounds can form molecular aggregates in size ranges of a few nanometers in an aqueous medium when their concentrations exceed a specific level. Incorporating these hydrophobic compounds has been observed to enhance the solubility of hydrophobic compounds into aggregate structures. Thus, this review introduces four transglycosylated compounds as food additives that can enhance the solubility and oral absorption of hydrophobic compounds. Here, transglycosylated hesperidin, transglycosylated rutin, transglycosylated naringin, and transglycosylated stevia are the focus as representative substances. Significantly, we observed that amorphous formations containing hydrophobic compounds with transglycosylated compounds improved solubility and oral absorption compared to untreated hydrophobic compounds. Moreover, combining transglycosylated compounds with hydrophilic polymers or surfactants enhanced the solubilizing effects on hydrophobic compounds. Furthermore, the enhanced solubility of hydrophobic compounds improved their oral absorption. Transglycosylated compounds also influenced nanoparticle preparation of hydrophobic compounds as a dispersant. This study demonstrated the benefits of transglycosylated compounds in developing supplements and nutraceuticals of hydrophobic compounds with poor aqueous solubility.
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Affiliation(s)
- Hiromasa Uchiyama
- Department of Formulation Design and Pharmaceutical Technology, Faculty of Pharmacy, Osaka Medical and Pharmaceutical University, Takatsuki, Osaka, Japan
| | - Kazunori Kadota
- Department of Formulation Design and Pharmaceutical Technology, Faculty of Pharmacy, Osaka Medical and Pharmaceutical University, Takatsuki, Osaka, Japan
| | - Yuichi Tozuka
- Department of Formulation Design and Pharmaceutical Technology, Faculty of Pharmacy, Osaka Medical and Pharmaceutical University, Takatsuki, Osaka, Japan
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Tang Z, Fan X, Chen Y, Gu P. Ocular Nanomedicine. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2022; 9:e2003699. [PMID: 35150092 PMCID: PMC9130902 DOI: 10.1002/advs.202003699] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/28/2020] [Revised: 10/31/2021] [Indexed: 05/07/2023]
Abstract
Intrinsic shortcomings associated with conventional therapeutic strategies often compromise treatment efficacy in clinical ophthalmology, prompting the rapid development of versatile alternatives for satisfactory diagnostics and therapeutics. Given advances in material science, nanochemistry, and nanobiotechnology, a broad spectrum of functional nanosystems has been explored to satisfy the extensive requirements of ophthalmologic applications. In the present review, the recent progress in nanosystems, both conventional and emerging nanomaterials in ophthalmology from state-of-the-art studies, are comprehensively examined and the role of their fundamental physicochemical properties in bioavailability, tissue penetration, biodistribution, and elimination after interacting with the ophthalmologic microenvironment emphasized. Furthermore, along with the development of surface engineering of nanomaterials, emerging theranostic methodologies are promoted as potential alternatives for multipurpose ocular applications, such as emerging biomimetic ophthalmology (e.g., smart electrochemical eye), thus provoking a holistic review of "ocular nanomedicine." By affording insight into challenges encountered by ocular nanomedicine and further highlighting the direction of future studies, this review provides an incentive for enriching ocular nanomedicine-based fundamental research and future clinical translation.
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Affiliation(s)
- Zhimin Tang
- Department of OphthalmologyShanghai Ninth People's HospitalShanghai Jiao Tong University School of MedicineShanghai Key Laboratory of Orbital Diseases and Ocular OncologyShanghai200011P. R. China
| | - Xianqun Fan
- Department of OphthalmologyShanghai Ninth People's HospitalShanghai Jiao Tong University School of MedicineShanghai Key Laboratory of Orbital Diseases and Ocular OncologyShanghai200011P. R. China
| | - Yu Chen
- Materdicine LabSchool of Life SciencesShanghai UniversityShanghai200444P. R. China
| | - Ping Gu
- Department of OphthalmologyShanghai Ninth People's HospitalShanghai Jiao Tong University School of MedicineShanghai Key Laboratory of Orbital Diseases and Ocular OncologyShanghai200011P. R. China
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Chen Z, Higashi K, Ueda K, Moribe K. Transition from Amorphous Cyclosporin A Nanoparticles to Size-Reduced Stable Nanocrystals in a Poloxamer 407 Solution. Mol Pharm 2022; 19:188-199. [PMID: 34843257 DOI: 10.1021/acs.molpharmaceut.1c00721] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Amorphous drug nanoparticles usually exhibit low storage stability. A comprehensive understanding of the molecular states and physicochemical properties of the product is indispensable for designing stable formulations. In the present study, an amorphous cyclosporin A (CyA) nanosuspension with a mean particle size of approximately 370 nm was prepared by wet bead milling with poloxamer 407 (P407). Interestingly, the prepared amorphous CyA nanoparticles were transformed into uniform CyA nanocrystals with a reduced mean particle size of approximately 200 nm during storage at 25 °C. The CyA nanocrystals were stably maintained for at least 1 month. The particle morphologies and molecular structures of the CyA nanosuspensions before and after storage were thoroughly characterized by cryogenic transmission electron microscopy and magic-angle spinning nuclear magnetic resonance spectroscopy, respectively. They revealed that the freshly prepared amorphous CyA nanoparticles (∼370 nm) were secondary particles composed of aggregated primary particles with an estimated size of 50 nm. A portion of P407 was found to be entrapped at the gaps between the primary particles due to aggregation, while most of P407 was dissolved in the solution either adsorbing at the solid/liquid interface or forming polymeric micelles. The entrapped P407 is considered to play an important role in the destabilization of the amorphous CyA nanoparticles. The resultant CyA nanocrystals (∼200 nm) were uniform single crystals of Form 2 hydrate and showed corner-truncated bipyramidal features. Owing to the narrow particle size distribution of the CyA nanocrystals, the rate of Ostwald ripening was slow, giving long-term stability to the CyA nanocrystals. This study provides new insights into the destabilization mechanism of amorphous drug nanoparticles.
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Affiliation(s)
- Ziqiao Chen
- Graduate School of Pharmaceutical Sciences, Chiba University, 1-8-1 Inohana, Chuo-ku, Chiba 260-8675, Japan
| | - Kenjirou Higashi
- Graduate School of Pharmaceutical Sciences, Chiba University, 1-8-1 Inohana, Chuo-ku, Chiba 260-8675, Japan
| | - Keisuke Ueda
- Graduate School of Pharmaceutical Sciences, Chiba University, 1-8-1 Inohana, Chuo-ku, Chiba 260-8675, Japan
| | - Kunikazu Moribe
- Graduate School of Pharmaceutical Sciences, Chiba University, 1-8-1 Inohana, Chuo-ku, Chiba 260-8675, Japan
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Polyether fluorinated amphiphilic diblock polymer: Preparation, characterization and application as drug delivery agent. Eur Polym J 2022. [DOI: 10.1016/j.eurpolymj.2021.110872] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Ganguly R, Kumar S, Nath S, Basu M, Aswal VK. Unusual Growth and Hydration Characteristics of Oil Solubilized Micelles in Aqueous Pluronic Systems. J Phys Chem B 2021; 125:10578-10588. [PMID: 34495673 DOI: 10.1021/acs.jpcb.1c04450] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Lipophile induced modulations of self-assembly characteristics in aqueous Pluronic systems merit attention because of wide-ranging uses of Pluronics as solubilizing agents of lipophilic substances. In this paper, we report unusual evolutions of structural and hydration properties in lavender essential oil (LO) solubilized Pluronic P85 aqueous micellar systems as a function of micellar volume fraction and temperature. Our DLS, SANS, and viscometry studies show that the spherical-to-wormlike micellar structural transition observed in 1% P85 solutions upon solubilization of LO quite unexpectedly gets suppressed with increased P85 concentration to ≥5%. Detailed SANS studies reveal that the core sizes of the oil solubilized micelles cannot attain the threshold value required for the onset of structural transition at higher copolymer concentrations due to their progressive shrinking with an increase in P85 concentration. Oil solubilized P85 solutions show two cloud points and very interestingly exhibit micellar growth upon cooling to their lower cloud points. Steady state fluorescence studies explain this based on increasing dehydration of micellar corona with a decrease in temperature, very much opposite to what is observed in pure aqueous Pluronic systems. The results give new insight into viscous flow properties and low temperature storage possibilities of oil solubilized aqueous Pluronic systems.
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Affiliation(s)
- R Ganguly
- Chemistry Division, Bhabha Atomic Research Centre, Mumbai 400085, India
| | - S Kumar
- Solid State Physics Division, Bhabha Atomic Research Centre, Mumbai 400085, India
| | - S Nath
- Radiation & Photochemistry Division, Bhabha Atomic Research Centre, Mumbai 400085, India
| | - M Basu
- Chemistry Division, Bhabha Atomic Research Centre, Mumbai 400085, India
| | - V K Aswal
- Solid State Physics Division, Bhabha Atomic Research Centre, Mumbai 400085, India
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