Physical and chemical parameters that mimic the physiological niche of the human body have an influence on stem cell fate by creating directional signals to cells. Micro/nano cell-patterned polydimethylsiloxane (PDMS) substrates, due to their ability to mimic the physiological niche, have been widely used in surface modification. Integration of other factors such as the biochemical coating on the surface can achieve more similar microenvironmental conditions and promote stem cell differentiation to the target cell line. Herein, we investigated the effect of physical topography, chemical functionalization by acid bone lysate (ABL) nanocoating, and the combined functionalization of the bone proteins’ nanocoated surface and the topographically modified surface. We prepared four distinguishing surfaces: plain PDMS, physically modified PDMS by 3D cell topography patterning, chemically modified PDMS with bone protein nanocoating, and chemically modified nano 3D cell-imprinted PDMS by bone proteins (ABL). Characterization of extracted ABL was carried out by Bradford staining and sodium dodecyl sulfate polyacrylamide gel electrophoresis analysis, followed by the MTT assay for evaluation of cell viability on ABL-coated PDMS. Moreover, field emission scanning electron microscopy and profilometry were used for the determination of optimal coating thickness, and the appropriate coating concentration was identified and used in the study. The binding and retention of ABL to PDMS were confirmed by Fourier transform infrared spectroscopy and bicinchoninic acid assay. Sessile drop static water contact angle measurements on substrates showed that the combined chemical functionalization and nano 3D cell-imprinting on the PDMS surface improved surface wettability by 66% compared to plain PDMS. The results of ALP measurement, alizarin red S staining, immunofluorescence staining, and real-time PCR showed that the nano 3D cell-imprinted PDMS surface functionalized by extracted bone proteins, ABL, is able to guide the fate of adipose derived stem cellss toward osteogenic differentiation. Eventually, chemical modification of the cell-imprinted PDMS substrate by bone protein extraction not only improved the cell adhesion and proliferation but also contributed to the topographical effect itself and caused a significant synergistic influence on the process of osteogenic differentiation.

Cell-imprinted polydimethylsiloxane substrates, in terms of their ability to mimic the physiological niche, low microfabrication cost, and excellent biocompatibility were widely used in tissue engineering. Cells inside the mature cells' cell-imprinted PDMS pattern have been shown in previous research to be capable of being differentiated into a specific mature cell line. On the other hand, the hydrophobicity of PDMS substrate leads to weak cell adhesion. Moreover, there was no guarantee that the cells would be exactly located in the cavities of the cells' pattern. In many studies, PDMS surface was modified by plasma treatment, chemical modification, and ECM coating. Hence, to increase the efficiency of cell-imprinting method, the concavity region created by the cell-imprinted pattern is conjugated with collagen. A simple and economical method of epoxy silane resin was applied for the selective protein immobilization on the desired regions of the PDMS substrate. This method could be paved to enhance the cell trapping into the cell-imprinted pattern, and it could be helpful for stem cell differentiation studies. The applied method for selective protein attachment, and as a consequence, selective cell integration was assessed on the aligned cell-imprinted PDMS. A microfluidic chip created the aligned cell pattern. After Ar+ plasma and APTES treatment of the PDMS substrate, collagen immobilization was performed. The immobilized collagen was removed by epoxy silane resin stamp from the ridge area where the substrate lacked cell pattern and leaving the collagen only within the patterned areas. Coomassie brilliant blue staining was evaluated for selective collagen immobilization, and the collagen-binding stability was assessed by BCA analysis. MTT assay for the evaluation of cell viability on the modified surface was further analyzed. Subsequently, the crystal violet staining has confirmed the selective cell integration to the collagen-immobilized site on the PDMS substrate. The results proved the successfully selective collagen immobilization on the cell-imprinted PDMS and showed that this method increased the affinity of cells to attach inside the cell pattern cavity.

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: Magnetic nanoparticles (MNPs) have unique properties which have made them widely applicable in medicine and biology. Due to their responsiveness to external magnetic force, they are easy to work with. Functionalization of nanoparticles(NPs) effectively improves performance, increases stability in the body and acidic environment, and prevents the agglomeration of the particles. One of the important applications of these NPs is in the separation of materials as solid-phase extracting agents. On the other hand, functionalizing these NPs can increase the efficiency, stability, specificity, and sensitivity of the structure to separate the target. In this paper, various material separation studies have been collected and classified into several main groups based on material types. Study groups included functional MNPs for separating pathogen, organic and inorganic substances of environmental resources, removal of heavy metal ions, separation of biomolecules, isolation of cells, especially tumor cells, harvesting the microalgae. The results showed that this method has advantages such as high sensitivity and specificity, ease of use without needing an operator, requiring low costs, and is a time-saving technique not requiring sample preparation and concentration.

Physical and chemical parameters that mimic the physiological niche of the human body have an influence on stem cell fate by creating directional signals to cells. Micro/nano cell patterned polydimethylsiloxane (PDMS) substrates, due to their ability to mimic the physiological niche, have been widely used in surface modifications. Integration of other factors such as the biochemical coating on the surface can achieve more similar microenvironmental conditions and promote stem cell differentiation to the target cell line. Herein, we investigated the effect of physical topography, chemical functionalization by acid bone lysate (ABL) nanocoating, and the combined functionalization of bone proteins nanocoated surface and topographically edited surface. We have prepared four distinguishing surfaces: plain PDMS, physically modified PDMS by 3D cell topography pattern, chemically modified PDMS with bone proteins nanocoating, and chemically modified nano 3D cell-imprinted PDMS by bone proteins (ABL). Characterization of ABL was carried out by Bradford staining and SDS page analysis followed by the MTT assay for evaluation of cell viability on ABL coated PDMS. Moreover, FESEM and Profilometry for determination of optimal coating thickness were utilized and the best coating concentration was identified and selected. The binding and retention of ABL to PDMS were confirmed by FTIR and BCA analysis. Sessile drop static water contact angle measurements on substrates have shown that the combined chemical functionalization and nano 3D cell-imprinting on PDMS surface leads to better surface wettability by 68% compared to plain PDMS. Eventually, the results of ALP measurement, Alizarin red S staining, Immunofluorescence staining, and real-time PCR have shown that nano 3D cell-imprinted PDMS surface functionalized by extracted bone proteins, ABL, is able to guide the fate of ADSCs toward osteogenic differentiation. Eventually, chemical modification of the cell-imprinted PDMS substrate by bone proteins extraction, not only improved the cell adhesion and proliferation but also contributed to the topographical effect itself and caused a significantly synergistic influence on the process of osteogenic differentiation.

Cisplatin is one of the most useful drugs in chemotherapy, which have several therapeutic properties. Nevertheless, this drug carries some side effects. In order to reduce such effects, nanotechnology has been a great help. In this study pegylated nanoniosomal Cisplatin was prepared through reverse phase evaporation technique. Certain ratios of span 60, cholesterol and polyethylene glycol (3000 Da) were synthesized to prepare pegylated nanoniosomal Cisplatin. The mean diameter, size distribution and zeta potential of pegylated nanoniosomal containing drug and without drug was measured 205.5±4.60 nm, 0.253±0.0036 and-21.4 mv; 251.1±3.93 nm, 0.058±0.0075 and-22.6 mv, respectively using Zetasizer. Encapsulation and drug loading efficiency of pegylated nanoniosomal Cisplatin was determined by spectrophotometry method that were 48.2±2.05% and 4.38±0.28%, respectively. The percent of drug released from niosomes was performed by dialysis for 48 hours. The amount of released drug from niosomes indicated that 82.73±1.36% of drug released into the PBS. Also, this study investigated the cytotoxicity effect of pegylated nanoniosomal Cisplatin using MTT assay. The results showed that IC50 of the pegylated nanoniosomal Cisplatin formulation is less than free drug on C6 cell line.