We report a new theranostic device based on lead sulfide quantum dots (PbS QDs) with optical emission in the near infrared wavelength range decorated with affibodies (small 6.5 kDa protein-based antibody replacements) specific to the cancer biomarker human epidermal growth factor receptor 2 (HER2), and zinc(II) protoporphyrin IX (ZnPP) to combine imaging, targeting and therapy within one nanostructure. Colloidal PbS QDs were synthesized in aqueous solution with a nanocrystal diameter of ∼5 nm and photoluminescence emission in the near infrared wavelength range. The ZHER2:432 affibody, mutated through the introduction of two cysteine residues at the C-terminus (Afb2C), was used as capping ligand to form Afb2C-PbS QDs that have a high binding affinity for HER2, which is overexpressed in several types of cancer including breast cancer. Afb2C-PbS QDs were further modified by conjugation with ZnPP, which acts as an anticancer agent. The biological activity of these QDs was tested against SKBR3 (HER2-positive) and MDA-MB-231 (HER2-normal) breast cancer cells, with results showing that ZnPP-Afb2C-functionalized PbS QDs were successfully targeted to the HER2-overexpressing cancer cells and induced cell apoptosis thanks to the conjugation with ZnPP. These results expand the use of the QD nanoplatform with the formulation of novel nanomaterials for targeted delivery and combined imaging and therapy via direct surface-protein interaction.
Objectives: Recently, there have been important advances in the clinical application of targeted hybrid near-infrared (NIR) fluorescent-radioactive tracers. ICG-99mTc-nanocolloid, for example, is already being used by some centres for sentinel lymph node biopsy in head and neck cancer. The radioactive component allows imaging at depths which would not be possible with NIR alone and, once exposed, the NIR fluorescence reporter can be imaged at very high resolution. Gamma detection is currently carried out with a separate hand-held gamma camera or with a non-imaging probe. Visualisation of NIR fluorescence during surgery requires a dedicated NIR camera, several of which are available commercially. We describe a novel hand-held hybrid NIR-gamm
... Show MoreThis research investigates new glasses which are best suitable for design of optical systems
working in the infrared region between 1.01 to 2.3μm. This work is extended to Oliva & Gennari
(1995,1998) research in which they found that the best known achromatic pairs are (BAF2-IRG2; SRF2-
IRG3; BAF2-IRG7; CAF2-IRGN6; BAF2-SF56A and BAF2-SF6). Schott will most probably stop the
production of these very little used and commercially uninteresting IRG glasses. In this work equally
good performances can be obtained by coupling BAF2, SRF2&CAF2 with standard glasses from Schott
or Ohara Company. The best new achromatic pairs found are (SRF2-S-TIH10; CAF2-S-LAL9; CAF2-SLAL13
and CAF2-S-BAH27). These new achromatic pai
Quantum dots (QDs) of cadmium sulfide (CdS) was prepared by chemical
reaction method with different potential of hydrogen (pH) values. The
morphological and optical measurements of cadmium sulfide QDs were considered
by atomic force microscopy (AFM), ultraviolet-visible (UV-VIS.) and
photoluminescence (PL) spectrometer respectively. The energy gap (Eg) was
calculated from photoluminescence spectra were found to be about 2.7, 2.6 and 2.5
eV at pH values 8, 10 and 12 respectively for CdS QDs. The decreasing of energy
gaps is rises from the effect the pH solution increases, which in turn leads to the
shifted of the PL spectrum toward red shifted, which creates the energy bands at
surface states are shallow bands.
Quantum dots of CdSe, CdS and ZnS QDs were prepared by chemical reaction and used to fabricate organic quantum dot hybrid junction device. QD-LEDs were fabricated using ITO/TPD: PMMA/CdSe/Al, ITO/TPD: PMMA/CdS/Al and ITO/TPD: PMMA/ZnS/Al QDs devices which synthesized by phase segregation method. The hybrid white light emitting devices consists, of two-layers deposited successively on the ITO glass substrate; the first layer was of N, N’-bis (3-methylphenyl)-N, N’-bis (phenyl) benzidine (TPD) polymer mixed with polymethyl methacrylate (PMMA) polymers in ratio 1:1, while the second layer was 0.5wt% from each type of the (CdSe, CdS and ZnS) QDs for each device.The optical properties of QDs were characterized by UV-Vis. and photolum
... Show MoreCurcumin (Cur) possesses remarkable pharmacological properties, including cardioprotective, neuroprotective, antimicrobial, and anticancer activities. However, the utilization of Cur in pharmaceuticals faces constraints owing to its inadequate water solubility and limited bioavailability. To overcome these hurdles, there has been notable focus on exploring innovative formulations, with nanobiotechnology emerging as a promising avenue to enhance the therapeutic effectiveness of these complex compounds. We report a novel safe, effective method for improving the incorporation of anticancer curcumin to induce apoptosis by reducing the expression levels of miR20a and miR21. The established
ZnS:MnP2+P nanoparticles were prepared by a simple microwave irradiation method under mild condition. The starting materials for the synthesis of ZnS:MnP 2+P quantum dots were zinc acetate as zinc source, thioacetamide as a sulfur source, manganese chloride as manganese source (R & M Chemical) and ethylene glycol as a solvent. All chemicals were analytical grade products and used without further purification. The quantum dots of ZnS:MnP 2+P with cubic structure were characterized by X-ray powder diffraction (XRD), the morphology of the film is seen by scanning electron microscopy (SEM) also by field effect scanning electron microscopy (FESEM). The composition of the samples is analysed by EDS. UV-Visible absorption spectroscopy analysis
... Show MoreQuantum dots (QDs) can be defined as nanoparticles (NPs) in which the movement of charge carriers is restricted in all directions. CdTe QDs are one of the most important semiconducting crystals among other various types where it has a direct energy gap of about 1.53 eV. The aim of this study is to exaine the optical and structural properties of the 3MPA capped CdTe QDs. The preparation method was based on the work of Ncapayi et al. for preparing 3MPA CdTe QDs, and hen, the same way was treated as by Ahmed et al. via hydrothermal method by using an autoclave at the same temperature but at a different reaction time. The direct optical energy gap of CdTe QDs is between 2.29 eV and 2.50 eV. The FTIR results confirmed the covalent bonding betwee
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