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This paper is devoted to the investigation of N-isopropylacrylamide-based microgels as potential drug delivery systems and other pharmaceutical applications. Surfactant free emulsion polymerization (SFEP) and emulsion polymerization techniques were employed to copolymerize PNIPAM with acrylic acid (AA), with 3-acrylamidophenylboronic acid (3-APB) and (3-acrylamidopropyl)trimethylammonium bromide (ATMA), and with 1-vinylimidazole (VI). The resultant microgel particles exhibited multi-responsive behaviour being sensitive to changes in temperature, pH. The PNIPAM-co-3-APB-ATMA microgels were sensitive to concentration of glucose, whilst the PNIPAM-co-VI microgels were sensitive to certain metals, copper in particular. The microgel containing AA exhibited characteristic temperature-sensitive behaviour with volume a phase transition temperature (VPTT) in the range of 35°–40 °C and showed pH-sensitive features as the particles collapsed at low and swelled at high pH values. The microgels containing various concentration of VI were also examined on sensitivity to temperature and pH changes. The investigation of such microgels with increasing temperature showed similar behaviour to those containing AA as the microgel particles shrunk continuously and the LCST has been shifted to higher temperatures (in the range of 35°–45 °C). The particle size of these microgels was also investigated as a function of pH; the microgel particles swelled at low and collapsed at high pHs. The particle size of the PNIPAM-co-3-APB-ATMA microgels was investigated both as a function of temperature and glucose concentration. The microgels showed typical behaviour of PNIPAM microgels copolymerized with functional monomer (3-APB and ATMA) by continuous shrinking with increasing temperature and shifted LCST towards higher temperatures. Additionally, these microgels showed swelling behaviour with the increase of glucose concentration at physiological conditions, i.e. particles swelled in the range of glucose concentration between 0.1 and 10 mmol/L at 35 °C and pH 7.5. The behaviour of these microgels was also investigated at 35 °C and pH 8.5 as a function of glucose concentration. Although the swelling of the particles was slightly larger at pH 8.5, considerable swelling was also observed at pH 7.5 making them the first microgel system to be glucose sensitive at physiological pH and temperature. Swelling of the particles at the pH level of human blood (in range of 7.35–7.45) as well as having lower critical solution temperature in the range of temperature of the human body gives an opportunity to develop these microgel particles further as potential drug-delivery agents.