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To upkeep health of astronauts in a unique, isolated, and extreme environment of space is the primary goal for a successful space mission, hence, safe and efficacious medications are essential for the wellness of astronauts. Space medication has been challenged with problems related to efficacy. Along with altered physiology, one of the possible reasons could be instability of space medications in the presence of harsh spaceflight environmental conditions. Altered physical and chemical stability can result in reduced potency which can result in reduced efficacy. Right now, medicines from the International Space Station are replaced before their expiration. But, for longer duration missions to Mars or any other asteroid, there will not be any chance of replacement of medicines. Hence, it is desired that medicines maintain the shelf-life throughout the space mission. Stability of medicines used for short term or long term space missions cannot be judged by drug stability guidelines based on terrestrial environmental factors. Unique environmental conditions related to spaceflight include microgravity, excessive vibration, hard vacuum, humidity variation, temperature differences and excessive radiation, which may cause instability of medicines. This write-up provides a review of the problem and countermeasure approaches for pharmaceuticals exposed to the space environment. The first part of the article discusses thought processes behind outlining of International Conference on Harmonization drug stability guidelines, Q1A (R2) and Q1B, and its acceptance limits for accelerated stability study. The second part of the article describes the difference in the radiation environment of deep space compared to radiation environment inside the space shuttle based on penetration power of different types of radiation. In the third part of the article, various promising approaches are listed which can be used for assurance of space medicine stability. One of the approaches is the use of ground-based space simulation analogues and statistical treatment to data to calculate failure rate of drugs and probabilistic risk assessment. Another approach is to innovate storage and packaging technology using radiation harden polymer or using cryogenic temperatures., (Copyright © 2017 Elsevier B.V. All rights reserved.)

The effect of storage in space on the stability of vitamin B complex in two commercial vitamin tablets was examined. Multiple vitamin samples returned after storage on the space shuttle and International Space Station (ISS) along with two ground control and three positive control groups were included in the study. Content of vitamin B(3) in the tablets and in vitro dissolution rate were determined using a modified high performance liquid chromatographic assay from USP/NF 2010. Results indicate that vitamin B(3) in one of the brands tested (#2) may be subject to marginal degradation after storage on ISS for 4 months as indicated by the chromatograms for all six tablets showing a split peak appearing as a notch at the peak tip. Chromatograms were not different for ground and flight samples for Brand #1 suggesting that this may be more suitable for use in space., (Copyright © 2011 Elsevier B.V. All rights reserved.)

Recently, attention has been drawn to drug-induced phototoxic skin responses, and avoidance of this undesired side effect is necessary for pharmaceutical development. We previously proposed that determination of reactive oxygen species (ROS) generated from photoirradiated compounds would be effective for the prediction of the phototoxic potential. In this investigation, a high-throughput ROS assay system was developed using a multiwell plate and quartz reaction container. The experimental conditions of irradiance uniformity, UV intensity, exposure time, temperature and solvent systems were found to affect the generation of ROS, and thus the conditions of the ROS assay were optimized. The intra- and inter-day R.S.D. values for the determination of ROS from quinine (200 microM) irradiated at 250 W/m(2) for 1h was found to be less than 3.3 and 4.5%, respectively. The results from the ROS assay of 39 compounds allowed us to estimate classification criteria to identify the ability of phototoxic/photochemical responses. The developed assay system will be an effective tool for predicting the phototoxic potential of pharmaceutical candidates in early stage of pharmaceutical development.

This manuscript reports the usefulness of the determination of sulphathiazole (ST) using photochemically induced fluorescence (RTPF) and RTPF coupling with first derivative (D1-RTPF), and the determination of sulphanilamide (SAN) by meaning first derivative of the emission spectrum. By irradiating 5 min, with intense UV radiation, sulphathiazole, in ethanol:water 20:80 (v/v) solutions at pH 4.5-5.0, show fluorescence emission at 342 nm (lambdaex=251 nm). Under these conditions, a linear relation, fluorescence intensity-ST concentration, was found between 0.23 and 3.00 microg mL(-1) of ST. The method was applied for determining ST in a pharmaceutical drug. ST was also determined in honey by using the D1-RTPF signal, applying the standard addition method, and measuring at 324.8 nm. Under the same experimental conditions of pH and solvent, a fluorimetric method for determining SAN in presence of ST is proposed. Calibration graphs for SAN determination were established using the amplitude of the first derivative of the emission spectrum measured at 324.4 nm, as the analytical signal. This method has been applied to determining SAN in a pharmaceutical formulation.

We report the development of a new 'photochemical titration' actinometric method for measurement of UV-B (290-320 nm) and UV-A (320-400 nm) light dose during drug photostability testing. It is based upon photolysis of aqueous 2-nitrobenzaldehyde solution, a well-characterized reaction that has been previously demonstrated to be useful as an accurate and reliable actinometric method. Our new method can be performed by a chemical technician using only common reagents. It has been developed for use with xenon arc lamp illumination chambers which are commonly employed for drug photostability testing, but can be readily modified for use with the other illumination sources.