Cancer heterogeneity increasingly requires ultrasensitive techniques that allow early diagnosis for personalized treatment. In addition, they should preferably be non-invasive tools that do not damage surrounding tissues or contribute to body toxicity. In this context, liquid biopsy of biological samples such as urine, blood, or saliva represents an ideal approximation of what is happening in real time in the affected tissues. Plasmonic nanoparticles are emerging as an alternative or complement to current diagnostic techniques, being able to detect and quantify novel biomarkers such as specific peptides and proteins, microRNA, circulating tumor DNA and cells, and exosomes. Here, we review the latest ideas focusing on the use of plasmonic nanoparticles in coded and label-free surface-enhanced Raman scattering (SERS) spectroscopy. Moreover, surface plasmon resonance (SPR) spectroscopy, colorimetric assays, dynamic light scattering (DLS) spectroscopy, mass spectrometry or total internal reflection fluorescence (TIRF) microscopy among others are briefly examined in order to highlight the potential and versatility of plasmonics.

Controlled formation of hot spots in nanoparticle clusters endowed with colloidal stability results in reliable optical sensors capable of providing quantitative SERS responses.

Fast and versatile optical SERS methods represent a major advance in chemical analysis of environmental samples such as water. To date, however, these ultrasensitive methods are hindered by two key drawbacks: (i) colloidal stability and (ii) chemical diversity, both arising from the compositional complexity of natural samples. Here, we present an engineered material that, due to its unique microporous structure, imparts colloidal stability and provides selectivity while confining a densely populated film of gold nanoparticles optimized for the generation of large electromagnetic fields. The material is tested against natural water for the ultraquantification of dichlorodiphenyl-trichloroethane (DDT), a ubiquitous environmental pollutant.

Schizophrenia is a severe and disabling psychiatric disorder with a complex and multifactorial etiology. The lack of consensus regarding the multifaceted dysfunction of this ailment has increased the need to explore new research lines. This research makes use of proteomics data to discover possible analytes associated with psychoneuroimmune signaling pathways in schizophrenia. Thus, we analyze plasma of 45 patients [10 patients with first-episode schizophrenia (FES) and 35 patients with chronic schizophrenia] and 43 healthy subjects by label-free liquid chromatography–tandem mass spectrometry. The analysis revealed a significant reduction in the levels of glia maturation factor beta (GMF-β), the brain-derived neurotrophic factor (BDNF), and the 115-kDa isoform of the Rab3 GTPase-activating protein catalytic subunit (RAB3GAP1) in patients with schizophrenia as compared to healthy volunteers. In conclusion, GMF-β, BDNF, and 115-kDa isoform of RAB3GAP1 showed significantly reduced levels in plasma of patients with schizophrenia, thus making them potential biomarkers in schizophrenia.

Schizophrenia is a progressive disorder characterized by multiple psychotic relapses. After every relapse, patients may not fully recover, and this may lead to a progressive loss of functionality. Pharmacological treatment represents a key factor to minimize the biological, psychological and psychosocial impact of the disorder. The number of relapses and the duration of psychotic episodes induce a potential neuronal damage and subsequently, neurodegenerative processes. Thus, a comparative study was performed, including forty healthy controls and forty-two SZ patients divided into first-episode psychosis (FEP) and chronic SZ (CSZ) subgroups, where the CSZ sub group was subdivided by antipsychotic treatment. In order to measure the potential neuronal damage, plasma levels of β-III tubulin, neurofilament light chain (Nf-L), and glial fibrillary acidic protein (GFAP) were performed. The results revealed that the levels of these proteins were increased in the SZ group compared to the control group (P < 0.05). Moreover, multiple comparison analysis showed highly significant levels of β-III tubulin (P = 0.0002), Nf-L (P = 0.0403) and GFAP (P < 0.015) in the subgroup of CSZ clozapine-treated. In conclusion, β-III tubulin, Nf-L and GFAP proteins may be potential biomarkers of neurodegeneration and progression in SZ. Schizophrenia (SZ) is a complex, severe and heterogeneous disorder. Unfortunately, its aetiology and pathophysiology remains unclear 1. Although schizophrenia can occur at any age, the average age of onset tends to be in the late teens to the early 20s for men, and the late 20s to early 30s for women, and its deteriorating course makes SZ the most disabling psychiatric disorder 2. SZ has been explained both by neurodevelopmental and neurodegenerative models, which include neuronal damage and grey matter abnormalities 3,4. Both models may be complementary, and four stages can be proposed in the course of SZ 5-11 (Fig. 1). Moreover, the duration of untreated psychosis (DUP) is a critical period during schizophrenia course. Accumulating evidence suggests that a longer DUP is associated with clinical deterioration, including increased symptoms severity, cognitive and functioning declines, and poorer response to antipsychotics 12,13. SZ patients treated immediately after the FEP will suffer less cognitive impairment and disability 14-17. Cognitive deficits are considered part of the core symptoms of SZ 18. Both abnormalities in prenatal life and in the early childhood neurodevelopment are associated with SZ, and they may explain the early cognitive decline that characterizes this disorder 8,19. Pathological neurodevelopment described in SZ patients may be explained

Herein we illustrate an effective protocol to boost the optical enhancing properties of gold nanostars.

Supercrystals, made of ordered plasmonic nanoparticles (NPs) in close contact, turn out as efficient SERS substrates. However, the production of highly homogeneous structures implies precise control over a multitude of parameters including quality of the building blocks, solvent evaporation rate, and surface chemistry interactions. To pursue this goal, different approaches using templates to self-assembly NPs have been developed in recent years. Here, we review the most common procedures employing two different substrates, planar and patterned templates. Several approaches and strategies are described showing the optical properties of the resulted supercrystals and their behavior as SERS substrates.

Herein, we present an optimized bottom-up approach for the fabrication of homogeneous small spherical silver nanoparticles, with average diameter sizes ranging from 10 to 30 nm and the associated plasmon resonances located between 390 and 410 nm. The presented method relies on the use of tiny amounts of Fe­(III) as the silver dopant during the growth process, which enables the production of very homogeneous nanoparticles (standard deviations <6%). The characterization of the obtained materials with surface-enhanced Raman scattering spectroscopy shows optical enhancing properties similar to, or even better than, those observed with standard silver nanoparticles. Moreover, these noble nanomaterials are also endorsed with an intrinsic magnetic functionality.