PMID- 32197438
OWN - NLM
STAT- PubMed-not-MEDLINE
LR  - 20200928
IS  - 2076-3921 (Print)
IS  - 2076-3921 (Electronic)
IS  - 2076-3921 (Linking)
VI  - 9
IP  - 3
DP  - 2020 Mar 18
TI  - Gelatin-Based Hydrogels for the Controlled Release of 
      5,6-Dihydroxyindole-2-Carboxylic Acid, a Melanin-Related Metabolite with Potent 
      Antioxidant Activity.
LID - 10.3390/antiox9030245 [doi]
LID - 245
AB  - The ability of gelatin-based hydrogels of incorporating and releasing under 
      controlled conditions 5,6-dihydroxyindole-2-carboxylic acid (DHICA), a 
      melanin-related metabolite endowed with marked antioxidant properties was 
      investigated. The methyl ester of DHICA, MeDHICA, was also tested in view of its 
      higher stability, and different solubility profile. Three types of gelatin-based 
      hydrogels were prepared: pristine porcine skin type A gelatin (HGel-A), a 
      pristine gelatin cross-linked by amide coupling of lysines and glutamic/aspartic 
      acids (HGel-B), and a gelatin/chitosan blend (HGel-C). HGel-B and HGel-C differed 
      in the swelling behavior, showed satisfactorily high mechanical strength at 
      physiological temperatures and well-defined morphology. The extent of 
      incorporation into all the gelatins tested using a 10% w/w indole to gelatin 
      ratio was very satisfactory ranging from 60 to 90% for either indoles. The 
      kinetics of indole release under conditions of physiological relevance was 
      evaluated up to 72 h. The highest values were obtained with HGel-B and HGel-C for 
      MeDHICA (90% after 6 h), and an appreciable release was observed for DHICA 
      reaching 30% and 40% at 6 h for HGel-B and HGel-C, respectively. At 72 h, DHICA 
      and MeDHICA were released at around 30% from HGel-A at pH 7.4, with an increase 
      up to 40% at pH 5.5 in the case of DHICA. DHICA incorporated into HGel-B proved 
      fairly stable over 6 h whereas the free compound at the same concentration was 
      almost completely oxidized. The antioxidant power of the indole loaded gelatins 
      was monitored by chemical assays and proved unaltered even after prolonged 
      storage in air, suggesting that the materials could be prepared in advance with 
      respect to their use without alteration of their efficacy.
FAU - Alfieri, Maria Laura
AU  - Alfieri ML
AD  - Department of Chemical Sciences, University of Naples Federico II, I-80126 
      Naples, Italy.
FAU - Pilotta, Giovanni
AU  - Pilotta G
AD  - Department of Biotechnology and Biosciences, University of Milano-Bicocca, 
      I-20126 Milan, Italy.
FAU - Panzella, Lucia
AU  - Panzella L
AUID- ORCID: 0000-0002-2662-8205
AD  - Department of Chemical Sciences, University of Naples Federico II, I-80126 
      Naples, Italy.
FAU - Cipolla, Laura
AU  - Cipolla L
AUID- ORCID: 0000-0003-2678-8329
AD  - Department of Biotechnology and Biosciences, University of Milano-Bicocca, 
      I-20126 Milan, Italy.
FAU - Napolitano, Alessandra
AU  - Napolitano A
AUID- ORCID: 0000-0003-0507-5370
AD  - Department of Chemical Sciences, University of Naples Federico II, I-80126 
      Naples, Italy.
LA  - eng
PT  - Journal Article
DEP - 20200318
PL  - Switzerland
TA  - Antioxidants (Basel)
JT  - Antioxidants (Basel, Switzerland)
JID - 101668981
PMC - PMC7139803
OTO - NOTNLM
OT  - 5,6-dihydroxyindole-2-carboxylic acid
OT  - antioxidant activity
OT  - controlled release
OT  - cross-linked hydrogel
OT  - gelatin
COIS- The authors declare no conflict of interest.
EDAT- 2020/03/22 06:00
MHDA- 2020/03/22 06:01
PMCR- 2020/03/18
CRDT- 2020/03/22 06:00
PHST- 2020/02/27 00:00 [received]
PHST- 2020/03/13 00:00 [revised]
PHST- 2020/03/16 00:00 [accepted]
PHST- 2020/03/22 06:00 [entrez]
PHST- 2020/03/22 06:00 [pubmed]
PHST- 2020/03/22 06:01 [medline]
PHST- 2020/03/18 00:00 [pmc-release]
AID - antiox9030245 [pii]
AID - antioxidants-09-00245 [pii]
AID - 10.3390/antiox9030245 [doi]
PST - epublish
SO  - Antioxidants (Basel). 2020 Mar 18;9(3):245. doi: 10.3390/antiox9030245.