Spectroscopy is widely used to characterize pharmaceutical products or processes, especially due to its desirable characteristics of being rapid, cheap, non-invasive/non-destructive and applicable both off-line and in-/at-/on-line. Spectroscopic techniques produce profiles containing a high amount of information, which can profitably be exploited through the use of multivariate mathematic and statistic (chemometric) techniques.
The determination of 5‑hydroxymethylfurfural (HMF) content in honey samples of different botanical origin by a NIR-chemometrics-based approach is reported. Spectral regions, statistical models, scatter and derivative correction together with smoothing pre-treatment were examined and selected on the basis of correlation coefficient and root mean square errors for both the calibration (R2cand RMSEC) and cross-validation (R2vand RMSECV).
Thymidine phosphorylase (TP) is an enzyme that is up-regulated in a wide variety of solid tumors, including breast and colorectal cancers. It is involved in tumor growth and metastasis, for this reason it is one of the key enzyme to be inhibited, in an attempt to prevent tumor proliferation. However, it also plays an active role in cancer treatment, through its contribution in the conversion of the anti-cancer drug 5-fluorouracil (5-FU) to an irreversible inhibitor of thymidylate synthase (TS), responsible of the inhibition of the DNA synthesis.
A novel type of graphene-like quantum dots, synthesized by oxidation and cage-opening of C60 buckminsterfullerene, has been studied as a ?uorescent and absorptive probe for heavy-metal ions. The lattice structure of such unfolded fullerene quantum dots (UFQDs) is distinct from that of graphene since it includes both carbon hexagons and pentagons. The basic optical properties, however, are similar to those of regular graphene oxide quantum dots.
Zn-salophen complexes are a promising class of fluorescent chemosensors for nucleotides and nucleic acids. We have investigated, by means of IRMPD spectroscopy experiments and quantum chemical calculations, the structure of the host-guest complexes formed by two efficient Zn-salophen receptors and dihydrogen phosphate or adenosine 5'-monophosphate (AMP) anions. In the host-guest complexes the phosphate group is bound with a Zn. O(phosphate) bond. In addition, a hydrogen bond can be formed between the PO. H group and one of the oxygen atoms of the salophen structure.
Improving the efficacy of gene therapy vectors is still an important goal toward the development of safe and efficient gene therapy treatments. S/MAR (scaffold/matrix attached region)-based vectors are maintained extra-chromosomally in numerous cell types, which is similar to viral-based vectors. Additionally, when established as an episome, they show a very high mitotic stability.
The mechanisms by which microRNAs control pediatric high-grade gliomas (pHGGs) have
yet to be fully elucidated. Our studies of patient-derived pHGG tissues and of the pHGG cell line
KNS42 revealed down-regulation in these tumors of three microRNAs, specifically miR-107, miR-181c,
and miR-29a-3p. This down-regulation increases the proliferation of KNS42 cells by de-repressing
expression of the Notch2 receptor (Notch2), a validated target of miR-107 and miR-181c and a
This paper presents a versatile low-cost procedure for complex permittivity measurements of liquids from 400 MHz to 5 GHz. Our procedure uses handheld instrumentation and custom software for data acquisition and postprocessing. The purpose is to replace the benchtop vector network analyzer (VNA) generally used in such applications with a portable and cheaper handheld spectrum analyzer used in the VNA mode.
Modelling the dynamics of a solution requires a
deep comprehension of the aqueous medium. In this work we
investigate different aqueous solutions through terahertz time domain
spectroscopy in order to gain a better understanding of
the water’s structure and it’s relation with the system of ions
solved in it. The results suggest a biphasic model of water; we
expect the two phases and their equilibrium at a given
temperature to be a determinant factor in the dynamics of the
molecules solved in it.
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