<p>Penelitian terkait pengaruh komposisi α-keratin/alginat terhadap kapasitas adsorpsi logam berat besi (Fe) telah dilakukan. Penelitian ini bertujuan untuk mengetahui karakter dan optimasi adsorpsi dari bioadsroben komposit α-keratin/alginat terhadap daya serap logam berat Fe dalam larutan air. Proses preparasi bioadsorben α-keratin/alginat dilakukan dengan metode enkapsulasi pada larutan CaCl<sub>2</sub> 2% (b/v). Karakterisasi bioadsorben dilakukan menggunakan <em>Fourier Transform Infra-Red</em> (FTIR),<em> Scanning Electron Microscopy</em> (SEM)<em> </em>dan proses adsorbsi dilakukan dengan metode<em> batch</em>. Hasil karakterisasi IR pada komposit α-keratin/alginat menunjukkan terdapatnya serapan pada bilangan gelombang 1140-820,75 cm<sup>-1 </sup>yang merupakan reduksi gugus <em>mannuronate</em> dari alginat. Hal ini menunjukan bahwa alginat telah terikat secara kimia dengan α-keratin. Adsorpsi logam Fe (3 ppm) dalam larutan dilakukan dengan variasi komposisi α-keratin:alginat secara berturut-turut sebagai berikut 1:1; 1:2; 1:3; 2:1 dan 3:1 (b/b). Hasil pengukuran menggunakan <em>Atomic Absorption Spectroscopy</em> (AAS) dengan metode kurva kalibrasi standar menunjukkan komposisi optimum penyerapan logam Fe (3 ppm) adalah 1:2 dengan kapasitas adsorpsi sebesar 205,64 mg/g. Hasil karakterisasi SEM pada komposit α-keratin:alginat komposisi 1:2 (b/b) yang memberikan kemampuan adsorpsi yang terbesar menunjukkan bahwa permukaan rambut manusia tidak tertutup secara menyeluruh sehingga gugus aktif dan celah-celah kecil pada komposit dapat berperan dalam proses adsorpsi logam berat besi (Fe).</p><p><strong>The </strong><strong>Effect </strong><strong>o</strong><strong>f α-Keratin</strong><strong>/</strong><strong>Alginate Bioadsorbent Composition </strong><strong>on</strong><strong> </strong><strong>the </strong><strong>Adsorption Capacity </strong><strong>o</strong><strong>f Heavy Metal </strong><strong>of Iron </strong><strong>(Fe)</strong><strong>.</strong> A study of the influence of α-keratin-alginate composition on the heavy metal adsorption of Fe has been performed. The research aims to determinate the character and adsorption optimation of α-keratin/alginate composite for Fe adsorption in aqueous solution. The preparation α-keratin/alginate composite was conducted by encapsulation method in CaCl<sub>2 </sub>2% solution. The characterization of bioadsorbent was performed by Fourier Transform Infra-Red (FTIR), Scanning Electron Microscopy (SEM) and adsorption process was conducted by batch method. The FTIR result on α-keratin/alginate shows that adsorption at wavenumber of 1140-820.75 cm<sup>-1</sup> which indicates the reduction of mannuronate group from alginate. This suggests that alginate was chemically bound with α-keratin. The adsorption of Fe (3 ppm) in the solution was carried out with variation of composition α-keratin:alginate of 1:1; 1:2; 1:3; 2:1; and 3:1 (w/w). The measurement using AAS (atomic absorption spectroscopy)<em> </em>with standar calibration curve method showed that optimum composition of Fe (3 ppm) adsorption was 1:2 (w/w) with adsorption capacity of 205.64 mg/g. The SEM result on α-keratin/alginate 1:2 (w/w) which had the greatest adsorption capability shows that the surface of human hair was not completely closed thus the active groups and pores can play a role in the process of adsorption of heavy metal iron (Fe).</p>