Contents lists available at ScienceDirect Journal of Chromatography B journal homepage: www.elsevier.com/locate/jchromb HPLC-UV and spectrofuorimetric methods for simultaneous estimation of futicasone furoate and vilanterol in rabbit plasma: A pharmacokinetic study Durgawati Patel a , Kuldeep Kumar Namdev b , Kanika Verma b , Ritika Gururani b , Akansha Tiwari b , Puspendra Kumar c , Rikeshwer Prasad Dewangan d , Saikh Mohammad Wabaidur a,e , Swapnil Sharma b, ⁎ , Jaya Dwivedi a, ⁎⁎ a Department of Chemistry, Banasthali Vidyapith, Banasthali, Rajasthan 304022, India b Department of Pharmacy, Banasthali Vidyapith, Banasthali, Rajasthan 304022, India c KIET School of Pharmacy, KIET Group of Institutions, Ghaziabad, Uttar Pradesh 201206, India d Department of Pharmaceutical Chemistry, School of Pharmaceutical Education and Research, Jamia Hamdard, New Delhi 110062, India e Advanced Materials Research Chair, Department of Chemistry, King Saud University, Riyadh, Saudi Arabia ARTICLEINFO Keywords: Fluticasone HPLC-UV Vilanterol Pharmacokinetic study Spectrofuorimetry ABSTRACT Fluticasone furoate (FF) and vilanterol trifenatate (VT) is a widely prescribed combination in the management of asthma and chronic obstructive pulmonary disease. In the present study, two quantitative methods based on HPLC-UV and spectrofuorimetric analysis had been developed and validated for simultaneous estimation of FF and VT in rabbit plasma using baclomethasone as internal standard (ISTD). Analytes and ISTD were separated from plasma using simple step of protein precipitation with acetonitrile. Chromatographic separation was achieved on Spherisorb S5 ODS2 (250 mm × 4.6 mm, 5.0 µm) column using mobile phase that constitute acetonitrile-0.01% glacial acetic acid in water (70:30, v/v) and then detected on a UV detector at 235 nm wavelength. Spectrofuorimetric detection was performed using absorption/emission wavelength (λ abs/em ) of 286/352 nm and 362/407 nm for FF and VT, respectively. For both analytes, linearity ranged from 4–200 ng/mL to 10–200 ng/mL using HPLC-UV and spectrofuorimetric method, respectively. Methods were validated as per FDA recommendations. Statistical analysis revealed that these detection methods are statistically insignifcant diference and can be used interchangeably without any bias. Further, these methods were applied in phar- macokinetic study for simultaneous estimation of FF and VT in rabbit plasma. 1. Introduction The combination of an inhaled corticosteroids (ICS) and a long- acting beta 2 agonist (LABA) is recommended in maintenance therapy of asthma and chronic obstructive pulmonary disease (COPD) [1]. Fluti- casone furoate (FF) and vilanterol trifenatate (VT) is a novel combi- nation of ICS and LABA (brand name- Breo Ellipta of GlaxoSmithKline), available as oral inhalation powder for once daily administration. In- haled FF/VT combination at dose of 100/25 µg was frst approved by United States Food and Drug Administration (US FDA) in 2013 for the treatment of COPD [2]. Compared to administration of FF alone, combination of FF/VT provided a signifcant reduction in asthma as- sociated severe exacerbation with overall improved lung function during clinical studies [3,4]. In 2015, it received US FDA nod for the treatment of asthma in patient aged 18 years and older [2]. FF, a novel, enhanced-afnity glucocorticoid, contains a 17-α esters form of futicasone and 2-furoic acid. In comparisons to propionate ester form in futicasone propionate (FP), the ester form in FF provide enhanced glucocorticoid receptor afnity with remarkable stability against in-vivo bio-transformation and thus confers for once daily dose inasthmaandCOPD [5,6]. It is both structurally and pharmacologically diferent from FP and futicasone, and does not bio-transform into fu- ticasone during metabolism (not a pro-drug of futicasone). The intact chemical entity (steroidal backbone + ester) in FF is responsible for its superior therapeutic actions [7,8]. VT, a novel LABA has superior and prolong bronchodilator action then other LABAs (olodaterol, for- moterol, indacaterol) in management of asthma and COPD. VT and salmeterol (SAL) are therapeutically equivalent but the former has advantage of once daily dose while later requires administration in every 12h [9–11]. Following inhaled administration in human, peak https://doi.org/10.1016/j.jchromb.2019.121842 Received 5 August 2019; Received in revised form 15 October 2019; Accepted 17 October 2019 ⁎ Corresponding author. ⁎⁎ Mentor and Co-corresponding author. E-mail addresses: skspharmacology@gmail.com (S. Sharma), jayadwivedi1203@gmail.com (J. Dwivedi). Journal of Chromatography B 1132 (2019) 121842 Available online 21 October 2019 1570-0232/ © 2019 Elsevier B.V. All rights reserved. T