The application of metal nanoparticles as an efficient drug delivery system is one of the directions of cancer therapy development.However,this strategy requires precise information about how the drug interacts with t...The application of metal nanoparticles as an efficient drug delivery system is one of the directions of cancer therapy development.However,this strategy requires precise information about how the drug interacts with the applied nanocarrier.In this study,atomic force microscopy combined with infrared spectroscopy(AFM-IR)was used for the first time to investigate the erlotinib adsorption structure on two different types of 15 nm metal nanoparticle mono-layers,namely,silver nanoparticle(AgNP)and gold nanoparticle(AuNP)mono-layers.Because the metal nanoparticles are loosely bound samples,only the tapping AFM-IR mode is suitable for the collection of IR maps and spectra for such a system.The obtained results indicated the relevance of the AFM-IR technique for characterizing drug interactions with a metal mono-layer surface.The investigated drug interacts with the AgNPs mainly through phenyl rings and methoxy moieties,while quinazoline,amino,and ethoxy moieties appear to be farther from the surface.For the AuNPs,the interaction occurs through both the phenyl ring and the quinazoline moiety.Additionally,the aliphatic groups of erlotinib directly participate in this interaction.The novelty of the present work is also related to the use of the tapping AFM-IR mode to study metal NP mono-layers with a drug adsorbed on them.The collected IR maps for the most enhanced erlotinib bands show specific areas with very high signal intensity.The connection between these areas and the"hot spots"typical for the surface plasmon resonance phenomenon of metals is considered.展开更多
We propose a new analytical approach combining vibrational spectroscopy and acoustic tomography for the detection and characterization of vesicles inside Streptomyces bacteria. Using atomic force microscopy and infrar...We propose a new analytical approach combining vibrational spectroscopy and acoustic tomography for the detection and characterization of vesicles inside Streptomyces bacteria. Using atomic force microscopy and infrared spectroscopy （AFM-IR）, we detect the presence of triglyceride vesicles. Their sizes in depth are measured with high accuracy using mode synthesizing atomic force microscopy （MS-AFM）. We conducted a comparative study of AFM-IR and MS-AFM, and highlighted the advantages of the coupling of these techniques in having a full characterization （chemical, topographical, and volumetric） of a biological sample. With these complementary techniques, a complete access to the vesicle size distribution has been achieved with an accuracy of less than 50 nm. A 3D reconstruction of bacteria showing the in-depth distribution of vesicles is given to underline the great potential of the acoustic method.展开更多
基金This work was supported by the National Science Centre Poland(No.2016/21/D/ST4/02178 to N.P.).N.P.gratefully acknowledges the financial support of the French Government and the French Embassy in Poland.These researches were also supported by the Paris Ile-de-France Region-DIM Materiaux anciens et patrim oniaux.The m easurem ents were partly perform ed using the equipm ent purchased in the frame of the project co-funded by the MatopolskaRegional Operational Program Measure 5.1 Krakow Metropolitan Areaas an important hub of the European Research Area for 2007-2013,project no.MRP0.05.01.00-12-013/15e.
文摘The application of metal nanoparticles as an efficient drug delivery system is one of the directions of cancer therapy development.However,this strategy requires precise information about how the drug interacts with the applied nanocarrier.In this study,atomic force microscopy combined with infrared spectroscopy(AFM-IR)was used for the first time to investigate the erlotinib adsorption structure on two different types of 15 nm metal nanoparticle mono-layers,namely,silver nanoparticle(AgNP)and gold nanoparticle(AuNP)mono-layers.Because the metal nanoparticles are loosely bound samples,only the tapping AFM-IR mode is suitable for the collection of IR maps and spectra for such a system.The obtained results indicated the relevance of the AFM-IR technique for characterizing drug interactions with a metal mono-layer surface.The investigated drug interacts with the AgNPs mainly through phenyl rings and methoxy moieties,while quinazoline,amino,and ethoxy moieties appear to be farther from the surface.For the AuNPs,the interaction occurs through both the phenyl ring and the quinazoline moiety.Additionally,the aliphatic groups of erlotinib directly participate in this interaction.The novelty of the present work is also related to the use of the tapping AFM-IR mode to study metal NP mono-layers with a drug adsorbed on them.The collected IR maps for the most enhanced erlotinib bands show specific areas with very high signal intensity.The connection between these areas and the"hot spots"typical for the surface plasmon resonance phenomenon of metals is considered.
文摘We propose a new analytical approach combining vibrational spectroscopy and acoustic tomography for the detection and characterization of vesicles inside Streptomyces bacteria. Using atomic force microscopy and infrared spectroscopy （AFM-IR）, we detect the presence of triglyceride vesicles. Their sizes in depth are measured with high accuracy using mode synthesizing atomic force microscopy （MS-AFM）. We conducted a comparative study of AFM-IR and MS-AFM, and highlighted the advantages of the coupling of these techniques in having a full characterization （chemical, topographical, and volumetric） of a biological sample. With these complementary techniques, a complete access to the vesicle size distribution has been achieved with an accuracy of less than 50 nm. A 3D reconstruction of bacteria showing the in-depth distribution of vesicles is given to underline the great potential of the acoustic method.
