Sebastian Thompson

Madrid Institute for Advanced Studies | IMDEA

Heat is of fundamental importance in many cellular processes such as cell metabolism, cell division and gene expression. (1-3) Accurate and noninvasive monitoring of temperature changes in individual cells could thus help clarify intricate cellular processes and develop new applications in biology and medicine. Here we report the use of green fluor...

Controlling and monitoring temperature at the single cell level has become pivotal in Biology and Medicine. Indeed, temperature influences many intracellular processes and is also involved as an activator in novel therapies. Aiming to assist such developments, several approaches have recently been proposed to probe cell temperature in vitro. None o...

A universal method for inactivating enzymes on demand is introduced, which involves irradiating nanorod-bound enzymes with near-infrared light. The subsequent generation of plasmonic heat denatures the enzymes selectively without damaging other proteins or cell membranes present in the same solution.

In the last decade, technological advances in chemistry and photonics have enabled real‐time measurement of temperature at the nanoscale. Nanothermometers, the probes specifically designed to relay these nanoscale temperature changes provide a high degree of temperature, temporal, and spatial resolution and precision. Several different approaches h...

Temperature is a key parameter that influences all biochemical reactions. Optical methods take preference in measuring temperature due to their non-invasive manner, spatial accuracy and ability to measure local changes in real time. From these methods, fluorescence anisotropy-based methods are particularly advantageous since they are less affected...

Measurement of intracellular temperature in a fast, accurate, reliable, and remote manner is crucial for the understanding of cellular processes. Nanothermometers based on the green fluorescence protein (GFP) are of special interest because intracellular temperature readouts can be obtained from the analysis of the polarization state of its lumines...

Fluorescent microscopy has enabled the study of intracellular processes and revealed the most intricate details of the subcellular structure. This has benefitted not only the basic biological science, but also has had an impact in numerous biomedical applications. Basic fluorescent sensing techniques use the change in the absolute emission of a flu...

There remains a need for techniques to monitor thermal processes at high spatiotemporal resolution, with myriad potential applications in chemistry, biology, and engineering. Measurement of temperature from nanoscale molecular phenomena are particularly promising due to their general compatibility with biological systems. Among these phenomena, flu...

Temperature measurement at the nanoscale has brought insight to a wide array of research interests in modern chemistry, physics, and biology. These measurements have been enabled by the advent of nanothermometers, which relay nanoscale temperature information through the analysis of their intrinsic photophysical behavior. In the past decade, severa...

Gold nanoparticles have become essential tools used in nanobiotechnology due to their tunable plasmonic properties and low toxicity in biological samples. Among the available approaches for imaging gold nanoparticles internalized by cells, hyperspectral techniques stand out due to their ability to simultaneously image and perform spectral analysis...

Photodynamic therapy (PDT) is a non-invasive treatment widely applied to different cancers. The goal of PDT is the photo-induced destruction of cancer cells by the activation of different cell death mechanisms, including apoptosis and/or necrosis. Recent efforts focusing on understanding the mechanisms of cell death activated by PDT find that it de...

Almost 15 years ago, the URI prefoldin-like complex was discovered by Krek and colleagues in immunoprecipitation experiments conducted in mammalian cells with the aim of identifying new binding partners of the E3 ubiquitin-protein ligase S-phase kinase-associated protein 2 (SKP2) (Gstaiger et al. Science 302(5648):1208–1212, 2003). The URI prefoldi...

A method is proposed for controlling the number of nanoparticles bound to cell membranes via RGDS peptide-integrin interactions. It consists of propelling nanoparticles bearing the peptides with enzymes (glucose oxidase), which disrupts biomolecular interactions as a function of the concentration of enzyme substrate (glucose).

In this manuscript we report on a new type of self-assembled plasmonic nanostructure called gold suprashells, which are assembled around superparamagnetic iron oxide nanoparticle (SPION) cores. Gold suprashells have multiple surface plasmon resonances over a broad vis-NIR wavelength range, which makes them useful in applications where broadband abs...

A new method is introduced for self-assembling citrate-capped gold nanoparticles into supraparticles with crystallographically aligned building blocks. It consists in confining gold nanoparticles inside a cellulos acetate membrane. The constituent nanoparticles are in close contact in the superstructure, and therefore generate hot spots leading to...

Prostate Cancer (PC) is the second leading cause of cancer deaths in American men. While prostate specific antigen (PSA) test has been widely used for screening PC, >60% of the PSA detected cancers are indolent, leading to unnecessary clinical interventions. An alternative approach, active surveillance (AS), also suffer from high expense, discomfor...

A new method is introduced for self-assembling citrate-capped gold nanoparticles into supraparticles with crystallographically aligned building blocks. It consists in confining gold nanoparticles inside a cellulos acetate membrane. The constituent nanoparticles are in close contact in the superstructure, and therefore generate hot spots leading to...

We previously established that spectroscopic microscopy can quantify subdiffraction-scale refractive index (RI) fluctuations in a label-free dielectric medium with a smooth surface. However, to study more realistic samples, such as biological cells, the effect of rough surface should be considered. In this Letter, we first report an analytical theo...

Introduction: An approach to radioimmunotherapy (RIT) of metastatic melanoma is the targeting of melanin pigment with monoclonal antibodies (mAbs) to melanin radiolabeled with therapeutic radionuclides. The proof of principle experiments were performed using a melanin-binding antibody 6D2 of IgM isotype radiolabeled with a β emitter (188)Re and de...

The photophysical properties of a chlorin, isobacteriochlorin, and bacteriochlorin built on a core tetrapentafluorophenylporphyrin (TPPF20 ) and the non-hydrolysable para thioglycosylated conjugates of these chromophores are presented. The photophysical characterization of these compounds was done in three different solvents to correlate to differe...

A characteristic of cancer cells is the generation of lactate from glucose in spite of adequate oxygen for oxidative phosphorylation. This property - known as the "Warburg effect" or aerobic glycolysis - contrasts with anaerobic glycolysis, which is triggered in hypoxic normal cells. The Warburg effect is thought to provide a means for cancer cells...

The facile synthesis and photophysical properties of three nonhydrolyzable thioglycosylated porphyrinoids are reported. Starting from meso-perfluorophenylporphyrin, the nonhydrolyzable thioglycosylated porphyrin (PGlc₄), chlorin (CGlc₄), isobacteriochlorin (IGlc₄), and bacteriochlorin (BGlc₄) can be made in 2-3 steps. The ability to append a wide r...

While cancer is still an implacable disease, many cancers can be cured if they are diagnosed in an early stage. Recently, it was reported that the transformation from normal cells to cancer cells can change their mechanoelastic properties to become softer and more deformable. If some cancer cells are more deformable, then a progressive increase of...

Porphyrins bearing sugars and other motifs are proposed for a variety of therapeutic applications. Non-hydrolysable glyco conjugates of porphyrins can be formed in rapid, room temperature reacting in greater than 90% yields from tetraperfluorophenyporphyrin. Additional functional groups can be appended using the same chemistry but different stoichi...

A water-soluble tetra-S-glycosylated porphyrin (P-Glu(4)) is absorbed by MDA-MB-231 human breast cancer cells whereupon irradiation with visible light causes necrosis or apoptosis depending on the concentration of the porphyrin and the power of the light. With the same amount of light irradiation power (9.4 W m(-2)), at 10-20 microM concentrations...

A spectroscopic device for monitoring the temperature of aqueous solutions is presented. It uses a 950 nm light emission diode as light source and two photodiodes as detectors. Temperature is monitored following the thermally induced absorbance changes of the water-OH second overtone (approximately 960 nm). A linear response between the light absor...

Cathepsin B (CB) is a lysosomal cysteine proteinase synthesized as a zymogen of 39-47 kilodaltons (kD), which is subsequently converted into an active single- chain form of 33 kD (CB33) and, by additional processing, into the active 2-chain form containing a heavy chain of 27-29 kD (CB(27-29)) and a light chain of 4-6 kD. Increased or altered CB ex...