Resveratrol (RSV) is well known for its many beneficial activities, but its unfavorable physicochemical properties impair its effectiveness after systemic and topical administration; thus, several strategies have been investigated to improve RSV efficacy. With this aim, in this work, we synthesized a novel RSV triester with trolox, an analogue of vitamin E with strong antioxidant activity. The new RSV derivative (RSVTR) was assayed in vitro to evaluate its antioxidant and anti-glycation activity compared to RSV. RSVTR chemical stability was assessed at pH 2.0, 6.8, and 7.2 and different storage temperatures (5 °C, 22 °C, and 37 °C). An influence of pH stronger than that of temperature on RSVTR half-life values was pointed out, and RSVTR greatest stability was observed at pH 7.2 and 5 °C. RSVTR showed a lower antioxidant ability compared to RSV (determined by the oxygen radical absorbance capacity assay) while its anti-glycation activity (evaluated using the Maillard reaction) was significantly greater than that of RSV. The improved ability to inhibit the glycation process was attributed to a better interaction of RSVTR with albumin owing to its increased topological polar surface area value and H-bond acceptor number compared to RSV. Therefore, RSVTR could be regarded as a promising anti-glycation agent worthy of further investigations.

A synthetic dual-target mu opioid peptide receptor/delta opioid peptide receptor anti-nociceptive ligand, named LP2, has emerged as a promising candidate for the management of acute and/or persistent pain, but its lipophilicity limits further developments as a therapeutic agent. In this work, to allow designing aqueous formulations of LP2 for parenteral administration, solid lipid nanoparticles (SLNs) were investigated as LP2 nanocarriers. LP2-loaded SLNs were prepared by the phase-inversion temperature method, showing good technological properties (small mean particle, size, low polydispersity index, good stability). As LP2 was a diastereoisomeric mixture of 2R/2S-LP2, an HPLC method was developed to identify and quantify each diastereoisomer, and this method was used to assess LP2 in vitro release from SLNs. The developed method, based on reverse-phase chromatography using an isocratic mobile phase consisting of 50% methanol and 50% triethanolamine at 0.3% (pH = 3 with trifluoroacetic acid), allowed efficient separation of 2R- and 2S-LP2 peaks and reliable quantification with intra- and inter-day precision and accuracy within the acceptability limit, expressed as relative standard deviation set at ≤15%. The results of this study suggest that the incorporation of LP2 into SLNs could be a promising strategy to design suitable formulations for further pharmacological studies involving LP2.