Stereo Coverage and Overall Stiffness of Biomaterial Arrays Underly Parts of Topography Effects on Cell Adhesion

Abstract

Surface topography is a biophysical factor affecting cell behaviors, yet the underlying cues are still not clear. Herein, we hypothesized that stereo coverage and overall stiffness of biomaterial arrays on the scale of single cells underly parts of topography effects on cell adhesion. We fabricated a series of microarrays (micropillar, micropit, and microtube) of poly(L-lactic acid) (PLLA) using mold casting based on pre-designed templates. The characteristic sizes of array units were less than that of a single cell, and thus, each cell could sense the micropatterns with varied roughness. With human umbilical vein endothelial cells (HUVECs) as the model cell type, we examined spreading areas and cell viabilities on different surfaces. "Stereo coverage" was defined to quantify the actual cell spreading fraction on a topographic surface. Particularly in the case of high micropillars, cells were confirmed not able to touch the bottom and had to partially hang among the micropillars. Then, in our opinion, a cell sensed the overall stiffness combining the bulk stiffness of the raw material and the stiffness of the culture medium. Spreading area and single cell viability were correlated to coverage and topographic feature of the prepared microarrays in particular with the significantly protruded geometry feather. Cell traction forces exerted on micropillars were also discussed. These findings provide new insights into the surface modifications toward biomedical implants.

A Sequential Electrospinning of a Coaxial and Blending Process for Creating Double-Layer Hybrid Films to Sense Glucose

“…By HSL conversion of the response color of 1–15 mmol/L, the color phase angle of each color was obtained, and its angle value was linearly fit, yielding R 2 = 0.96707 ( Figure 9 c), which already includes the human blood glucose concentration range (3.9–6.1 mmol/L), meeting the needs for simple testing of human blood glucose. Today, new kinds of polymers [ 80 , 81 , 89 ], organic and inorganic nanoparticles [ 90 , 91 ], and novel strategies for biomedical applications [ 92 , 93 , 94 , 95 , 96 , 97 ] are continuously reported. These achievements can be borrowed into the design and development of electrospun nanofibers, and thus promote new kinds of sensors and biomedical devices.…”

Recent Progress of the Preparation and Application of Electrospun Porous Nanofibers

“…Electrospun porous nanofibers have become a research hotspot, so with the progress and development of electrospinning technology and the unremitting efforts of scientists and researchers, more excellent performances of electrospun porous nanofibers can be developed. The expansion of their applications can be further strengthened along with the fast developments in modern science and technology, such as encapsulating new functional ingredients [ 182 , 183 , 184 ] and additives [ 185 , 186 ], exploring new types of filament-forming polymeric matrices [ 187 , 188 ], being introduced to popular life-improving applications [ 189 , 190 , 191 , 192 , 193 , 194 ], taking advantage of new strategies of synthesizing materials [ 195 , 196 ], and drawing support from traditional techniques for production on a large scale [ 197 , 198 ].…”

Achieving Long-Acting Local Analgesia Using an Intelligent Hydrogel Encapsulated with Drug and pH Regulator

“…Biomaterials have various applications in the fields of tissue replacement, tissue engineering, regenerative medicine, and drug delivery. − Carriers such as liposomes, nanoparticles, and microspheres have been used to encapsulate local anesthetics for developing long-acting analgesia formulations. , However, besides the relatively low encapsulation efficiency of drugs and complex preparation methods of these formulations, those particles are, unlike our in situ -formed physical hydrogel, not easy to retain in the injection site, and thus, these particle-form formulations exhibit limited long-term efficacy as usual. A star local anesthetic formulation with the trade name Exparel is BUP multivesicular liposome, which is used via surgical site infiltration .…”