Exploring the Potential of Montmorillonite as an Antiproliferative Nanoagent against MDA-MB-231 and MCF-7 Human Breast Cancer Cells.

Unlike MCF-7 cells, MDA-MB-231 cells are unresponsive to hormone therapy and often show resistance to chemotherapy and radiotherapy. Here, the antiproliferative effect of biocompatible montmorillonite (Mt) nanosheets on MDA-MB-231 and MCF-7 human breast cancer cells was evaluated by MTT assay, flow cytometry, and qRT-PCR. The results showed that the Mt IC50 for MDA-MB-231 and MCF-7 cells in a fetal bovine serum (FBS)-free medium was ~50 and ~200 µg/mL, and in 10% FBS medium ~400 and ~2000 µg/mL, respectively. Mt caused apoptosis in both cells by regulating related genes including Cas-3, P53, and P62 in MDA-MB-231 cells and Bcl-2, Cas-8, Cas-9, P53, and P62 in MCF-7 cells. Also, Mt arrested MCF-7 cells in the G0/G1 phase by altering Cyclin-D1 and P21 expression, and caused sub-G1 arrest and necrosis in both cells, possibly through damaging the mitochondria. However, fewer gene expression changes and more sub-G1 arrest and necrosis were observed in MDA-MB-231 cells, confirming the higher vulnerability of MDA-MB-231 cells to Mt. Furthermore, MDA-MB-231 cells appeared to be much more vulnerable to Mt compared to other cell types, including normal lung fibroblast (MRC-5), colon cancer (HT-29), and liver cancer (HepG2) cells. The higher vulnerability of MDA-MB-231 cells to Mt was inferred to be due to their higher proliferation rate. Notably, Mt cytotoxicity was highly dependent on both the Mt concentration and serum level, which favors Mt for the local treatment of MDA-MB-231 cells. Based on these results, Mt can be considered as an antiproliferative nanoagent against MDA-MB-231 cells and may be useful in the development of local nanoparticle-based therapies.

A simple smartphone-assisted paper-based colorimetric biosensor for the detection of urea adulteration in milk based on an environment-friendly pH-sensitive nanocomposite.

Urea is a common milk adulterant that falsely increases its protein content. Excessive consumption of urea is harmful to the kidney, liver, and gastrointestinal system. The conventional methods for urea detection in milk are time-consuming, costly, and require highly skilled operators. So, there is an increasing demand for the development of rapid, convenient, and cost-efficient methods for the detection of urea adulteration in milk. Herein, we report a novel colorimetric paper-based urea biosensor, consisting of a novel environment-friendly nanocomposite of halloysite nanotubes (HNT), that urease enzyme and an anthocyanin-rich extract, as a natural pH indicator are simultaneously immobilized into its internal and external surfaces. The biosensing mechanism of this biosensor is based on anthocyanin color change, which occurs due to urease-mediated hydrolysis of urea and pH increment of the environment. The colorimetric signal of this biosensor is measured through smartphone-assisted analysis of the mean RGB (Red-Green-Blue) intensity of samples and is capable of detecting urea with a detection limit of 0.2 mM, and a linear range from 0.5 to 100 mM. This biosensor has demonstrated promising results for the detection of urea in milk samples, in the presence of other milk adulterants and interferents.

Fungal Infected Adipose Stem Cells: The Effects of Novel Lipo-Niosome Nanoparticles Loaded with Amphotericin B and Thymus Essential Oil.

OBJECTIVE: In this study, we aimed to develop new Lipo-niosomes based nanoparticles loaded with Amphotericin B (AmB) and Thymus Essential Oil (TEO) and test their effectiveness in the treatment of fungal-infected human adipose stem cells (hASCs). MATERIALS AND METHODS: In this experimental study, optimal formulation of AmB and TEO loaded lipo-niosome (based on lipid-surfactant thin-film hydration method) was chemically, and biologically characterized. Therefore, encapsulation capacity, drug release, size, and the survival rate of cells with different concentrations of free and encapsulated AmB/ TEO were evaluated using the MTT method, and its antifungal activity was compared with conventional AmB. RESULTS: Lipo-Niosome containing Tween 60 surfactant: cholesterol: Dipalmitoyl phosphatidylcholine (DPPC): Polyethylene glycol (PEG) with a ratio of 20:40:60:3 were chosen as optimal formulation. Lipo-Niosomes entrapment efficiency was 94.15%. The drug release rate after 24 hours was 52%, 54%, and 48% for Lipo-AmB, Lipo-TEO, and Lipo-AmB/TEO, respectively. Physical and chemical characteristics of the Lipo-Niosomes particles indicated size of 200 nm and a dispersion index of 0.32 with a Zeta potential of -24.56 mv. Furthermore, no chemical interaction between drugs and nano-carriers was observed. The cell viability of adipose mesenchymal stem cells exposed to 50 µg/ml of free AmB, free TEO, and free AmB/TEO was 13.4, 58, and 36.9%, respectively. Whereas the toxicity of the encapsulated formulas of these drugs was 48.9, 70.8, and 58.3% respectively. The toxicity of nanoparticles was very low (8.5%) at this concentration. Fluorescence microscopic images showed that the antifungal activity of Lipo-AmB/ TEO was significantly higher than free formulas of AmB, TEO, and AmB/TEO. CONCLUSION: In this study, we investigated the efficacy of the TEO/AmB combination, in both free and encapsulatedniosomal form, on the growth of fungal infected-hASCs. The results showed that the AmB/TEO-loaded Lipo-Niosomes can be suggested as a new efficient anti-fungal nano-system for patients treated with hASCs.

Montmorillonite, a natural biocompatible nanosheet with intrinsic antitumor activity.

Montmorillonite (Mt) nanosheets are used in pharmaceutical products as both excipient and active ingredients. In addition, Mt can be used as a nanocarrier for oral delivery of drugs, including chemotherapy drugs, and as an embolic agent for tumor arterial embolization. It is noteworthy that, there is few conflicting evidence on the intrinsic antitumor activity of Mt. Hence, in this study, the antitumor potential of Mt was investigated using MRC-5, HT-29 and HepG2 cell lines. MTT assay revealed that, Mt possesses antiproliferative effect, which was concentration-dependent and affected by both protein level and cell type. However, this antiproliferative effect was not significantly affected by increasing the exposure time from 24 to 48 h. The results of flow-cytometry and qRT-PCR analyses showed that, Mt induced G0/G1-phase arrest in MRC-5 and HT-29 cells by modulating P21, P27 and Cyclin D1 genes, whereas it induced S-phase arrest in HepG2 cells probably by damaging DNA and up-regulating mTOR gene. The results also indicated that, Mt induced a high rate of apoptosis in all the cell lines by modulating anti/pro-apoptotic genes, as well as a rate of necrosis in HT-29. The apoptosis of MRC-5 and HT-29 cells was accompanied with up-regulation of P62 gene, suggesting autophagy-dependent apoptosis. In addition, in all the cell lines, Mt significantly enhanced the expression of executioner caspase-3. Based on these results, the biocompatible Mt nanosheets can act as antitumor agents. These findings may provide new applications of Mt in the field of cancer therapy.

Paper based colorimetric detection of miRNA-21 using Ag/Pt nanoclusters.

Abnormal expression of MicroRNA-21 (miRNA-21) is considered to be a reliable biomarker for the early diagnosis of cancer. In this work, a novel paper based biosensor was fabricated to detect sub-micro molar concentrations of miRNA-21 based on peroxidase mimetic activity of DNA-templated Ag/Pt nanoclusters (DNA-Ag/Pt NCs), which could catalyze the reaction of hydrogen peroxide and 3,3',5,5' tetramethylbenzidine (TMB), to produce a blue color. The Mechanism of reaction was based on the inhibition effect of miRNA-21 on peroxidase-like activity of nanosensor which resulted to quantitative determination of miRNA-21 concentration. It was found that miRNA-21 could be linearly detected in the range from 1-700 pM (A652 = 0.16x-0.96, R2 = 0.99; x = -log [miRNA-21]) with a detection limit of 0.6 pM. Moreover, a paper assay was carried out on a Y-shaped paper-based microfluidic device in order to use the distinctive features of micro-channels such as short response time, very low reagent volume, low fabrication cost, etc. After performing paper based assay, a good linear range was observed between 10-1000 pM (y = 0.06x+147.48, R2 = 0.99; x = [miRNA-21]) with detection limit of 4.1 pM. The practical application of proposed method for detection of miRNA-21 in real sample was assayed in the human urine sample and indicated the colorimetric method had acceptable accuracy.

Stability and loading properties of curcumin encapsulated in Chlorella vulgaris.

Curcumin (Cur), a polyphenols with pharmacological function, was successfully encapsulated in algae (Alg) cell (Chlorella vulgaris) as confirmed by fluorescence microscopy, thermogravimetric analysis (TGA), differential scanning calorimetry (DSC) and Fourier transform-infrared spectroscopy (FT-IR). Fluorescence micrographs, TGA, DSC and FTIR spectra suggested the hypothesis inclusion Cur in Nano-empty spaces inside cell wall of Alg. The TGA analysis showed that the thermal stability of Alg and Cur at algae/curcumin complex was 3.8% and 33% higher than their free forms at 0-300°C and 300-600°C ranges, respectively. After encapsulation in Alg cells, the photostability of Cur was enhanced by about 2.5-fold. Adsorption isotherm of Cur into Alg was fitted with the Freundlich isotherm. The microcapsules were loaded with Cur up to about 55% w/w which is much higher than other reported bio-carriers. In conclusion, the data proved that Chlorella vulgaris cell can be used as a new stable carrier for Cur.