fa Proanthocyanidins’ efficacy in stabilizing dentin collagen against enzymatic degradation: MALDI-TOF and FTIR analyses ترمیمی Cosmetic and Restorative Dentistry پژوهشي Research <p> <strong>Objectives </strong></p><p> To investigate grape seed extract proanthocyanidins’ (PA) capability in improving dentin collagen's sustainability in an enzymatic environment, given that the size and shape of the collagen samples, and the manner to apply PA are both clinically relevant.</p><p> <strong> Methods</strong> </p><p> Human dentin was sectioned into 6-μm-thick films. After demineralisation in 35wt% phosphoric acid for 15s, the films were subject to 30s of treatment at PA concentrations of 0% (control), 0.5%, 1%, 2%, 3.75%, 7.5% and 15% (w/w), respectively. The films were then digested in 0.1wt% collagenase for 1h and 24h. The amount of degraded collagen in the liquid digests was determined by MALDI-TOF mass spectroscopy. The trend of PA's incorporation into dentin collagen was analysed by ATR-FTIR. </p><p> <strong>Results</strong> </p><p> The control exhibited complete digestion in 1h. In contrast, collagen treated with 0.5% and 1% PA afforded 13.84±4.69% and an undetectable level of degradation, respectively in the first 1h of digestion, and additional 17.48±4.38% and 4.50±1.68%, respectively in the following 23h. Collagen treated with ≥2wt% PA was not significantly digested regardless of digestion time. FTIR spectroscopy revealed that PA incorporation was saturated at ≥2wt% PA. </p><p> <strong>Conclusion</strong></p><p>  Thirty seconds of PA treatment at 2wt% and above could provide optimal protection for dentin collagen against collagenase digestion. </p><p> <strong>Clinical significance</strong></p><p>  This study demonstrated PA's extraordinary efficiency in stabilizing demineralised dentin collagen when it is applied in a clinical relevant manner, and identified the optimal conditions for its utilization. </p><hr><p></p><p> <strong>Source: </strong>Journal of Dentistry</p><p><a href="http://www.jodjournal.com/article/S0300-5712(13)00087-0/abstract" target="_blank"><font color="#0000ff"> Full Text</font></a></p> Dentin collagen, Proanthocyanidins, Collagenase digestion, MALDI-TOF, ATR-FTIR 0 0 http://idai.ir/browse.php?a_code=A-10-32-2162&slc_lang=fa&sid=1 Yi Liu 100319475328460010160 100319475328460010160 No Yong Wang 100319475328460010161 100319475328460010161 Yes University of Missouri-Kansas City, School of Dentistry, 650 E. 25th St., Kansas City, MO