To aid oral therapeutic administration to infants, a novel delivery technology, referred to as a Therapeutic Nipple Shield (TNS), was previously developed. It consists of a silicone nipple shield device and a dosage form containing a therapeutic (or Active Pharmaceutical Ingredient (API)) to enable delivery during breastfeeding. A range of dosage forms were investigated in past literature, but sufficient API release into human milk had not been achieved. The presented work illustrates the delivery of iron sulphate pentahydrate from liquid-core sodium alginate hydrogels, inserted into a commercially available ultra-thin silicone nipple shield into human milk during in-vitro breastfeeding simulation. Release of iron was quantified employing absorbance measurements of a salicylic assay. An absolute recovery of 44.35 ± 5.43% of loaded iron(III)sulphate pentahydrate was obtained after 10.58 ± 0.09 g of human milk had passed through the nipple shield. This finding is superior to previous investigations involving the delivery of zinc from rapidly disintegrating tablets and non-woven fibres within a TNS. Due to their superior delivery properties, ease of fabrication and cost-efficiency, liquid-core sodium alginate hydrogels consequently represent a promising dosage form for use as part of the TNS. Further improvements can be made to enhance handling stability and shelf-life characteristics.