PMID- 33177935
OWN - NLM
STAT- PubMed-not-MEDLINE
LR  - 20220418
IS  - 2148-6247 (Electronic)
IS  - 1304-530X (Print)
IS  - 1304-530X (Linking)
VI  - 17
IP  - 5
DP  - 2020 Oct
TI  - Determination of the Physicochemical Properties of Piroxicam.
PG  - 535-541
LID - 10.4274/tjps.galenos.2019.82335 [doi]
AB  - OBJECTIVES: The aim of this study was to determine the acid dissociation constant 
      (pKa) of piroxicam using high performance liquid chromatography (HPLC) and 
      ultraviolet-visible (UV-Vis) spectrophotometry, and to determine the partition 
      coefficient (Log P), distribution coefficient (Log D), and "Log kw" values of 
      piroxicam using HPLC. MATERIALS AND METHODS: The HPLC studies were performed on a 
      reversed-phase ACE C18 (150x4.6 mm ID, 5 mum) column at a flow rate of 1.0 mL 
      min(-1). The detector was set to 360 nm. Log D at different pH values (3.0-6.5) 
      was examined with a phosphate buffer (20 mM) and acetonitrile (30:70 v/v) mixture 
      as the mobile phase. For pKa determination, HPLC studies were performed with a 
      mixture of phosphate buffer (20 mM) and methanol within the pH range of 
      3.50-6.00. Log kw measurements were performed with phosphate buffer (20 mM) and 
      MeOH (from 20:80 v/v to 10:90 v/v) mixtures within the pH range of 3.50-6.00. 
      UV-Vis spectrophotometric pKa measurements were performed at 285 nm wavelength. 
      RESULTS: The pKa value of piroxicam was found to be 5.3 by HPLC and 5.7 by UV-Vis 
      spectrophotometry. Log P of piroxicam was determined as 1.58 in our experimental 
      conditions. Log D values were 1.57, 1.57, 1.44, 1.13, and 0.46 for pH values of 
      3.17, 3.79, 4.44, 5.42, and 6.56, respectively. CONCLUSION: In the literature, 
      different Log P (3.1, 2.2, and 0.6) and pKa (6.3 and 4.8) values were reported 
      for piroxicam. The Log P (1.58) and pKa (5.3 and 5.7) values obtained for 
      piroxicam in our study were within the range of the literature values. All these 
      results indicate that different experimental approaches used for the 
      determination of physicochemical properties could provide different values. 
      Although UV spectrophotometry is easy to apply, HPLC is a unique technique for 
      simultaneous determination of pKa, Log D, and Log P values of compounds.
CI  - (c)Copyright 2020 Turk J Pharm Sci, Published by Galenos Publishing House.
FAU - CelebIer, Mustafa
AU  - CelebIer M
AUID- ORCID: 0000-0001-7712-5512
AD  - Hacettepe University Faculty of Pharmacy, Department of Analytical Chemistry, 
      Ankara, Turkey.
FAU - NennI, Merve
AU  - NennI M
AUID- ORCID: 0000-0003-3165-1060
AD  - Cukurova University Faculty of Pharmacy, Department of Analytical Chemistry, 
      Adana, Turkey.
FAU - Kaplan, Ozan
AU  - Kaplan O
AUID- ORCID: 0000-0001-7429-9349
AD  - Hacettepe University Faculty of Pharmacy, Department of Analytical Chemistry, 
      Ankara, Turkey.
FAU - AkgeyIk, Emrah
AU  - AkgeyIk E
AUID- ORCID: 0000-0002-6626-0150
AD  - Inonu University Faculty of Pharmacy, Department of Analytical Chemistry, 
      Malatya, Turkey.
FAU - Kaynak, Mustafa Sinan
AU  - Kaynak MS
AUID- ORCID: 0000-0003-2917-2407
AD  - Anadolu University Yunus Emre Vocational School, Department of Pharmacy, Program 
      in Pharmacy Services, Eskisehir, Turkey.
FAU - SahIn, Selma
AU  - SahIn S
AUID- ORCID: 0000-0001-5736-5906
AD  - Hacettepe University Faculty of Pharmacy, Department of Pharmaceutical 
      Technology, Ankara, Turkey.
LA  - eng
PT  - Journal Article
DEP - 20201030
PL  - Turkey
TA  - Turk J Pharm Sci
JT  - Turkish journal of pharmaceutical sciences
JID - 101717890
PMC - PMC7650726
OTO - NOTNLM
OT  - Log D
OT  - Log P
OT  - Log kw
OT  - Piroxicam
OT  - pKa
OT  - physicochemical properties
COIS- Conflicts of interest: No conflict of interest was declared by the authors. The 
      authors alone are responsible for the content and writing of the paper.
EDAT- 2020/11/13 06:00
MHDA- 2020/11/13 06:01
PMCR- 2020/10/01
CRDT- 2020/11/12 05:41
PHST- 2019/02/25 00:00 [received]
PHST- 2019/09/05 00:00 [accepted]
PHST- 2020/11/12 05:41 [entrez]
PHST- 2020/11/13 06:00 [pubmed]
PHST- 2020/11/13 06:01 [medline]
PHST- 2020/10/01 00:00 [pmc-release]
AID - 30172 [pii]
AID - 10.4274/tjps.galenos.2019.82335 [doi]
PST - ppublish
SO  - Turk J Pharm Sci. 2020 Oct;17(5):535-541. doi: 10.4274/tjps.galenos.2019.82335. 
      Epub 2020 Oct 30.