ABSTRACT
Biodegradable conjugated polymer nanoparticles (CPNs) were prepared for high mitochondrial targeting in live cancer cells. The degradable CPNs are nontoxic and specifically localized to the mitochondria of live tumor cells through macropinocytosis followed by intracellular degradation and trafficking.
Subject(s)
Mitochondria/metabolism , Nanoparticles/chemistry , Polymers/chemistry , Microscopy, Confocal , PinocytosisABSTRACT
Core-shell conjugated polymer nanoparticles (CPNs) were fabricated by complexing a semi-flexible, primary amine-containing conjugated polymer (CP) with hyaluronic acid (HA). Flexibility introduced in the rigid rod conjugated backbone allows backbone reorganization to increase π-π interaction under ionic complexation, resulting in core-shell nanoparticles with a hydrophobic CP core wrapped with a HA shell. The core-shell nanoparticles exhibited no cellular toxicity and high cancer cell specificity with minimal binding to normal cells.
ABSTRACT
The subcellular localization and toxicity of conjugated polymer nanoparticles (CPNs) are dependent on the chemical structure of the side chains and backbone. Primary amine-containing CPNs exhibit high Golgi localization with no toxicity. Incorporation of short ethylene oxide and tertiary amine side chains contributes to decreased Golgi localization and increased toxicity, respectively.
Subject(s)
Nanoparticles/chemistry , Polymers/chemistry , Amines/chemistry , Cell Survival/drug effects , Ethylene Oxide/chemistry , Golgi Apparatus/metabolism , HeLa Cells , Humans , Nanoparticles/toxicityABSTRACT
Previous work has demonstrated the ability to differentiate individuals based on the analysis of human scent hand odor chemicals. In this paper, a range of forensic biological specimens are shown to also have the ability to differentiate individuals based upon the volatile organic compounds (VOCs) present. Human VOC profiles from hand odor, oral fluid, breath, blood, and urine of 31 individuals were analyzed by solid-phase microextraction-gas chromatography-mass spectrometry (SPME-GC-MS) and combined methods of chromatogram comparison, Spearman rank correlation comparison, and principal component analysis. Intra-specimen comparisons demonstrated the distinguishability of individuals above 99%. Inter-specimen VOC profiles from the same individual were found to be too different to be used for scent-matching purposes, with Spearman rank coefficients below 0.15. A 6-month VOC profile monitoring of two individuals demonstrated the consistency of VOC profiles over time across specimens.
Subject(s)
Volatile Organic Compounds/analysis , Adult , Blood Chemical Analysis , Breath Tests , Female , Forensic Medicine , Gas Chromatography-Mass Spectrometry , Hand , Humans , Male , Odorants , Saliva/chemistry , Solid Phase Microextraction , Urine/chemistry , Young AdultABSTRACT
Understanding and controlling aggregation structures of conjugated polymers (CPs) in aqueous solutions is critical to improving the physical and photophysical properties of CPs for biological applications. Here, we present spectroscopic evidence, including nuclear magnetic resonance (NMR) spectroscopic results, that different organic acid treatment induces different aggregation structures and photophysical properties of CPs in water. Conjugated polymer nanoparticles (CPNs) were fabricated by treating a non-aqueous soluble, primary amine-containing poly(phenylene ethynylene) (PPE-NH(2)) with organic acids followed by dialysis. CPNs formed by acetic acid (AA) treatment (CPN-AAs) exhibit characteristics of loose aggregation with minimal π-π stacking, while CPNs formed by tartaric acid (TA) treatment (CPN-TAs) exhibit a high degree of π-π stacking among PPE-NH(2) chains. The controlled aggregation for a specific application was demonstrated by comparing the fluorescence quenching abilities of the CPN-AAs and the CPN-TAs. A doubled Stern-Volmer constant was obtained from the densely packed CPN-TAs compared to that of the loosely aggregated CPN-AAs.
ABSTRACT
Loosely aggregated conjugated polymer nanoparticles (CPNs) were used as nontoxic and efficient small interfering RNA (siRNA) delivery vehicles with delivery visualization. A significant down regulation (94%) of a target gene was achieved by transfection of HeLa cells with the CPNs/siRNA complexes, supporting CPN as a promising siRNA delivery carrier.
Subject(s)
Nanoparticles/chemistry , Polymers/chemistry , RNA, Small Interfering/metabolism , Actins/antagonists & inhibitors , Actins/genetics , Actins/metabolism , HeLa Cells , Humans , RNA InterferenceABSTRACT
In recent years, interest has increased regarding the identification of volatile organic compounds (VOCs) for metabolic profiling, human scent identification of the living and deceased, and diagnostic potentials for certain diseases that are known for its association with distinct odor. In this study, a method has been developed that is capable of sampling, identifying, and differentiating the VOCs present in various biological specimens of forensic importance (blood, breath, buccal cells, and urine) taken from the same individuals. The developed method requires a pretreatment step to remove targeted VOCs from the sampling apparatus prior to sampling of the individual specimens. The VOCs collected from the biological specimens were characterized by solid-phase microextraction and gas chromatography/mass spectrometry with ratios of the most abundant and frequent VOCs compared using qualitative and semiquantitative methods. Blood, breath, and buccal cells required extraction procedures ranging from 18 to 21 h in order to optimize the limit of detection, which averaged 5-15 ng across these specimens. The optimal method for measuring urine VOCs was complete in less than an hour; however, the limit of detection was higher with a range of 10-40 ng quantifiable. The demonstrated sensitivity and reproducibility of the methods developed allow for population studies of human scent VOCs from various biological specimen collection kits used in the forensic and clinical fields.
