* Ascorbic acid is easily oxidized and so is used as a reductant in photographic developer solutions (among others) and as a preservative.
* In fluorescence microscopy and related fluorescence-based techniques, ascorbic acid can be used as an antioxidant to increase fluorescent signal and chemically retard dye photobleaching.
* It is also commonly used to remove dissolved metal stains, such as iron, from fiberglass swimming pool surfaces.
* In plastic manufacturing, ascorbic acid can be used to assemble molecular chains more quickly and with less waste than traditional synthesis methods.
* Heroin users are known to use ascorbic acid as a means to convert heroin base to a water-soluble salt so that it can be injected.
* As justified by its reaction with iodine, it is used to negate the effects of iodine tablets in water purification. It reacts with the sterilized water, removing the taste, color, and smell of the iodine. This is why it is often sold as a second set of tablets in most sporting goods stores as Potable Aqua-Neutralizing Tablets, along with the potassium iodide tablets.
*Intravenous high-dose ascorbate is being used as a chemotherapeutic and biological response modifying agent. It is undergoing clinical trials.
* It is sometimes used as a urinary acidifier to enhance the antiseptic effect of methenamine.