A NOVEL RATIO DIFFERENCE SPECTROPHOTOMETRIC METHOD FOR THE SIMULTANEOUS DETERMINATION OF MOLNUPIRAVIR AND FAVIPIRAVIR IN BINARY MIXTURE

Öz

Objective: A ratio difference spectrophotometric method was developed for the determination of molnupiravir (MNP) and favipiravir (FVP) in binary mixtures, two antiviral agents of significance in COVID-19 therapy, and its applicability to the analysis of real samples was evaluated. Material and Method: Measurements were recorded with a UV-VIS spectrophotometer in the 200–300 nm wavelength range against water as a blank solution. While preparing the ratio spectra, the binary mixtures were divided by spectra of 5 µg/ml FVP and 5 µg/ml MNP, respectively. Calculations were performed using the differences in absorbance at wavelengths of 265 nm to 280 nm for MNP and 220 nm to 250 nm for FVP in the ratio spectra. Result and Discussion: The developed method exhibited linearity in the concentration range of 2.5–30.0 µg/ml for MNP and 2.5–30.0 µg/ml for FVP, and the detection limits were calculated as 99 ng/ml and 109 ng/ml, respectively. Recovery studies were performed on MNP capsules and FVP tablets, and the average recovery values were calculated as 99.82% and 100.30%, respectively.

Anahtar Kelimeler

• Antiviral drugs
• COVID-19
• favipiravir
• molnupiravir
• ratio difference

MOLNUPİRAVİR VE FAVİPİRAVİRİN İKİLİ KARIŞIMLARDA EŞZAMANLI TAYİNİ İÇİN YENİ BİR ORAN FARKI SPEKTROFOTOMETRİ YÖNTEMİ

Öz

Amaç: Bu çalışma kapsamında COVID-19 tedavisinde önemli bir yere sahip olan antiviral ilaçlardan molnupiravir (MNP) ve favipiravirin (FVP) ikili karışımlardan tayini için bir oran farkı spektrofotometri yöntemi geliştirilmesi ve gerçek numunlerden analiz için uygulanması amaçlanmıştır. Gereç ve Yöntem: Ölçümler UV spektrofotometre ile 200 – 300 nm dalga boyu aralığında kör çözelti olarak suya karşı kaydedilmiştir. Oran spektrumları hazırlanırken ikili karışımlar sırasıyla 5 µg/ml FVP ve 5 µg/ml MNP spektrumlarına bölünmüştür. Oran spektrumlarında MNP için 265 nm ile 280 nm, FVP için 220 nm ile 250 nm dalga boylarındaki absorbansların farkları kullanılarak hesaplamalar yapılmıştır. Sonuç ve Tartışma: Geliştirilen yöntem MNP için 2.5 – 30.0 µg/ml, FVP için 2.5 – 30.0 µg/ml konsantrasyon aralığında doğrusallık sergilemiş ve gözlenebilme sınırı değerleri sırasıyla 99 ng/ml ve 109 ng/ml olarak hesaplanmıştır. MNP kapsül ve FVP tabletlerden geri kazanım çalışmaları yapılmış ve ortalama geri kazanım değerleri sırasıyla %99.82 ve %100.30 olarak hesaplanmıştır.

Anahtar Kelimeler

• Antiviral ilaçlar
• COVID-19
• favipiravir
• molnupiravir
• oran farkı

Kaynakça

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