Controlled Assembly and Release of Retinoic Acid Based on the Layer-by-Layer Method

All-<i>trans</i> retinoic acid (RA) has been proved to play important roles in regulating cell growth in various types of cells. Yet most experiments were performed by adding RA in solution previously. In this Article, we focus on the incorporation of RA, as a negatively charged moiety, into layered polyelectrolyte films on surfaces by means of layer-by-layer (LbL) deposition, followed by adding of capping layers to regulate the release of RA from the films. The incorporated RA was designed to release over 5 days in buffer solution. The assembly and release of RA were verified by UV and QCM results. The controlled release of RA from multilayer films can serve as a model system to study the influence of small molecules on cell growth

Data Citation 2-2.tif

Participants’ results for GO thickness using different data analysis methods.</p

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Step height profile along the white line in Data Citation 1-1.  </p

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Step height profile along the white line in Figure 1-1. </p

Figure 1-1.png

AFM topography image of a graphene oxide flake.</p

table 2.docx

Values reported by each participant of the average flake thickness from the international.</p

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Histogram method for thickness measurement of GO flakes. </p

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Value of degree of equivalence (di) with their evaluated uncertainties for the submitted results of each participant from Table 4. </p

table 1.docx

Comparison of different analysis programs to measure the thickness of GO flakes.</p

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Average thickness of a GO flake for each participant from the ILC, with their associated uncertainties (ui) from Table 2. Here, the solid horizontal line represents the CRV (Tref) and the dashed horizontal lines are the standard uncertainty (uref) of the CRV. </p