We describe a simple and rapid method for determining the critical micelle concentration (CMC) of surfactants from fiber-optic measurements of refractive index. The refractive index of an aqueous surfactant solution was monitored as the surfactant concentration was increased using an automated dispensing system. On reaching the surfactant's CMC value, an abrupt change was observed in the rate of increase of the refractive index with increasing concentration. The measurement system provides rapid semiautomatic data collection and analysis, increasing the precision, sensitivity, and range of applicability of the technique while substantially decreasing the amount of manual intervention required. Measurements of CMC for sodium dodecyl sulfate (8.10mM), cetyltrimethylammonium chloride (1.58mM), and Triton X-100 (0.21mM) were in excellent agreement with values previously reported in the literature. The method is applicable to cationic, anionic, and nonionic surfactants, and it offers a facile, in situ, and sensitive means of detecting micelle formation over a broad range of CMC values larger than 10(-1)mM.
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http://dx.doi.org/10.1016/j.ab.2010.02.021 | DOI Listing |
Biomater Sci
January 2025
Zhejiang Key Laboratory of Smart BioMaterials, and College of Chemical and Biological Engineering, Zhejiang University, Hangzhou 310058, China.
Accurate imaging of tumor hypoxia is critical for early cancer diagnosis and clinical outcomes, highlighting the great need for its detection specificity and sensitivity. In this report, we propose a probe (HTRNP) that simultaneously has hypoxia-targeting and hypoxia-responsive capabilities to enhance the tumor hypoxia imaging efficiency. HTRNP was successfully prepared through the encapsulation of Pt(II)-tetrakis(pentafluorophenyl)porphyrin (PtPFPP), which exhibits hypoxia-dependent phosphorescence, within the amphiphilic block copolymer OPDMA-PF, which has hypoxia-targeting tertiary amine -oxide moieties and hydrophobic perfluorobenzene ring structures, which highly improved the loading content and water solubility of PtPFPP.
View Article and Find Full Text PDFBiomacromolecules
January 2025
Department of Biomedical Engineering, College of Design and Engineering, National University of Singapore, 15 Kent Ridge Crescent, Singapore 119276, Singapore.
Amphiphilic polymers with distinct polarity differences, known as sharp polarity contrast polymers (SPCPs), have gained much attention for their ability to form micelles with low critical micelle concentrations (CMCs) and potential in anticancer drug delivery. This study addresses the limited research on structure-property relationships of SPCPs by developing various SPCPs and exploring their physicochemical properties and biological applications. Specifically, the superhydrophobic aliphatic palmitoyl (Pal) was coupled to the superhydrophilic zwitterionic poly(2-methacryloyloxyethyl phosphorylcholine) (pMPC) to form Pal-pMPC diblock copolymers.
View Article and Find Full Text PDFPharmaceuticals (Basel)
January 2025
Department of Pharmacy Sciences, School of Pharmacy and Health Professions, Creighton University, Omaha, NE 68178, USA.
Inherited retinal disorders (IRDs) represent a group of challenging genetic conditions that often lead to severe visual impairment or blindness. The complexity of these disorders, arising from their diverse genetic causes and the unique structural and functional aspects of retinal cells, has made developing effective treatments particularly challenging. Recent advancements in gene therapy, especially non-viral nucleic acid delivery systems like liposomes, solid lipid nanoparticles, dendrimers, and polymersomes, offer promising solutions.
View Article and Find Full Text PDFFood Chem
January 2025
State Key Laboratory of Bioactive Molecules and Druggability Assessment, Guangdong Basic Research Center of Excellence for Natural Bioactive Molecules and Discovery of Innovative Drugs, Institute for Advanced and Applied Chemical Synthesis, College of Pharmacy, Jinan University, Guangzhou 510632, China; Guangdong Province Key Laboratory of Pharmacodynamic Constituents of TCM & New Drugs Research, College of Pharmacy, Jinan University, Guangzhou 510632, China; Anhui Jinhe Industrial Co., Ltd., Chuzhou 239200, China. Electronic address:
The nutritional characteristics of the tetrasaccharide stachyose prompted its incorporation into biosurfactants through esterification with fatty acid derivatives embodying 12-22 carbon chains. The resulting esters were evaluated for their surface active effects, emulsifying properties and capacities to form emulsions capable of the selective delivery of the anti-oxidant resveratrol. While such studies have revealed that those congeners embodying longer side-chains have higher critical micelle concentrations (CMC) and lower interfacial tensions, their hydrophilic-lipophilic balance (HLB) values fell within a tight range.
View Article and Find Full Text PDFGels
January 2025
Gene Engineering Laboratory, Feed Research Institute, Chinese Academy of Agricultural Sciences, Beijing 100081, China.
, a prevalent zoonotic pathogen, poses a significant threat to skin wound infections. This study evaluates the bactericidal efficacy of self-assembled peptide hydrogels, PPI45 and PPI47, derived from the defensin-derived peptide PPI42, against ATCC43300. The high-level preparation of PPI45 and PPI47 was achieved with yields of 1.
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