ABSTRACT
Heteroatom-doped carbon dots (CDs) have attracted extensive interest because of their improved elec-tronic and fluorescence properties with heteroatom doping. In this study, a new synthetic method for nitrogen (N) and sulfur (S) -doped CDs was developed via a hydrothermal method using methionine and citric acid as raw materials. The as-prepared CDs exhibit excellent optical properties and good bio-compatibility. The spherical N,S-doped CDs have an average diameter of 5 nm. They consist of C, O, N and S, and take on excellent water solubility due to the hydroxyl and carboxyl, amino groups on the surface. The CDs have a photoluminescence quantum yield of 13.8％ using quinine sulfate as a reference; the average fluorescence lifetime of the CDs was 3.67 ns. The CDs solution present good photoluminescence properties, and the maximum excitation wavelength and emission wavelength locate at 330 nm and 405 nm, respectively. In addition, their fluorescence intensity almost does not change under the condi-tions of acid, alkali, and high salt, which indicated their anti-photobleaching property and good light stability. Based on the good biocompatibility and strong fluorescence emission of the CDs, they can be used as fluorescent imaging reagents.
ABSTRACT
Objective To explore the application of erlotinib based targeting fluorescent probe in the detection of lung cancer.Methods The erlotinib based targeting fluorescent probe was prepared.The lung cancer cells of A-549 were selected as experimental group,and cervical cancer cells of CaSki,SiHa and C33-A were selected as control group.The A-549,CaSki,SiHa and C33-A cells were identified by 0.1 × 10-6,1 × 10-6,10 × 10-6 mol · L-1 fluorescent probe;the identification ability of erlotinib based targeting fluorescent probe on cells in the two groups was observed under the inverted fluorescence microscope.Results When the concentration of fluorescent probe was 10 × 10-6 mol · L-1,the strong fluorescence signal was observed in A-549 and CaSki cells,but the fluorescence signal was not observed almost in SiHa and C33-A cells.When the concentration of fluorescent probe was 1 × 10-6 mol · L-1,the strong fluorescence signal was observed in A-549 cells;the weak fluorescence signal was observed in C33A cells;the fluorescence signal was not observed almost in SiHa and C33-A cells.When the concentration of fluorescent probe was 0.1 × 10-6 mol · L-1,the strong fluorescence signal was observed in A-549 cells;the fluorescence signal was not observed almost in CaSki,SiHa and C33-A cells.Conclusion Erlotinib based targeting fluorescent probe can specifically recognize lung cancer A-549 cells.
ABSTRACT
The nanocomposites of poly-diallyldimethylammonium chloride (PDADMAC) and CdTe quantum dots (QDs) (i.e.QDs-PDADMAC nanocomposites) have been prepared based on electrostatic interaction and their fluorescence stability in aqueous solution has been investigated. MTT method(3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazoliumbromide method) was used to study their cytotoxicity and A549 lung cancer cell as a model cell was also used to evaluate their cellular imaging.It was shown that the fluorescence stability of QDs-PDADMAC nanocomposites was much better than that of bare QDs both in aqueous solution and cell.Meanwhile,QDs-PDADMAC nanocomposites display very low cytotoxicity in the low concentrations and better staining ability compared with QDs.QDs-PDADMAC nanocomposites will have great advantage on the cell analysis detection and imaging.
ABSTRACT
OBJECTIVE: Equivalent cross-relaxation rate (ECR) imaging is an MRI technique used to evaluate quantitatively a change in the protein-water interaction. We aimed to evaluate retrospectively the usefulness of ECR imaging for the histologic classification of malignant lymphoma (ML). MATERIALS AND METHODS: Institutional Review Board approval was obtained and all patients provided informed consent. The study subjects included 15 patients with untreated ML who were histologically diagnosed with follicular lymphoma (FL; n = 8) or diffuse large B-cell lymphoma (DLBCL; n = 7). All patients underwent ECR imaging and the offset frequency was set at 7 ppm. RESULTS: The median ECR values were 71% (range; 60.7 to 75.5) in FL and 54% (50.8 to 59.4) in DLBCL (p = 0.001). The median cellular density was 1.5 +/- 0.17 x 10(6) / mm2 in FL and 1.0 +/- 0.70 x 10(6) / mm2 in DLBCL (p = 0.001). The correlation coefficient between the ECR values and cellular density in ML was 0.88 (p = 0.001). In FL and DLBCL, assuming ECR value cut-off points of 60%, both sensitivity and specificity were 100%. CONCLUSION: A strong correlation between ECR and cellular density in ML is demonstrated and the ECR may be a useful technique to differentiate between FL and DLBCL.