A novel generic platform for chemical patterning of surfaces

Control over wettability via surface modification of porous gradients

“…Interestingly, earlier studies on chemically modified CF 3 flat surfaces were only able to achieve a contact angle of 120 º [33,39], while here the lateral gradient has clearly demonstrated the enhancement of hydrophobicity by means of graded surface roughness. 1000-3000 300-1000 100-300 50-100 20-50 [5][6][7][8][9][10][11][12][13][14][15][16][17][18][19][20] Pore Size (nm)…”

“…For example, the increasing demand for sophistication on biochip surfaces has motivated extensive studies of liquid-surface interaction [1,2]. It is important to note that biochip and material design usually involves tuning of wettability using surface chemistry [3][4][5][6] and in particular surface roughness [7,8] or a combination of texture and chemistry [9,10]. Surface wettability is a key factor in mediating fluid transport in confined spaces and across surfaces and it also influences adsorption of biomolecules and subsequent biological response.…”

Micrometer scale spacings between fibronectin nanodots regulate cell morphology and focal adhesions

“…On the other hand, most nanometer scale patterning processes lack pattern flexibility. In addition, they usually deliver a combination of topographical, biochemical and/or rigidity signals [10,11,17,26,27] rather than providing a pure biochemical signal, for example. While different types of signal are all crucial for cell response in order to dissect the contribution of each type of signal, surfaces that provide only that type of signal are essential.…”

“…There have been significant previous studies on patterning proteins on surfaces; however, one drawback has been the presence of both biochemical and topography or stiffness signals due to the lack of a better fabrication method at the time. Oxide layers that inevitably introduce topography variations have been used to provide regions for protein versus polymer adsorption [26,27]. In this case, the cells receive the biochemical signal (protein versus polymer) coupled to a topographical signal (high versus low regions on the surface).…”

“…EBL has been utilized to fabricate patterns of proteins on surfaces, and some of these patterned surfaces were also tested and shown to be functional at the cellular level [18,[26][27][28][29][30][31][32][33][34][35]. In one approach the resulting patterns present a purely biochemical signal because there are no differences in rigidity and the patterns are basically flat because adhesive patches have a thickness of only 2 nm [31].…”